Management of Information Technology for Solution Development

Question: Discuss about the Management of Information Technology for Solution Development. Answer: Introduction The assignment is the comparison of old concepts and theories on Solution Development and Delivery in Information Technology with the new current practices on the Solution Development and Delivery in IT. Literature review is included in this assignment which states the concepts, theories, facts about the Solution Development and Delivery in IT. Articles and books related to the Solution development delivery is analysed. Current Practices in the development and delivery involves the analysis in websites which tells about the new trends in Solution Development and Delivery in IT. Current practices describes the recent improvements in Information Technology in terms of Development delivery. Comparison is included which defines the differences between the literature review and the current practice on the Solution Development and Delivery. Solution Development is carried out by the separate development team in the company. If there occur any changes to the solution after the development process, then it makes its impact on the delivery process which is the final task in the cycle. So development and delivery is very much related in the solution. Literature Review According to (Qureshi, 2009), Solution development method is the composition of various components like Steps of procedure, methods, templates for standards, and managing the configuration. He says that the method of solution development gets differed according to the size of the company. In the study, the author analysed the small size companies development on solutions with big sized companies. He also states that the medium size and small size companies do not have their own method for developing the solution. He had proposed the methodology for the solution development which overheads the short-term projects. He concludes that the method for solution development is the foremost thing in the solution. Dingsyr and Lassenius (2016) says that the association between the customer and the vendor is the key factor in the solution development and in the delivery. He says that the relation between them can be maintained by increasing the focus on the value and by moving towards the deployment of the solution. The study says that the trends in the development of the solution mainly focuses on the value of the Business. According to (Laukkanen, Itkonen and Lassenius, 2017), Continuous solution delivery is one of the discipline involved in developing the solution. Once the solution is designed, developed and tested, it is ready for the release. The author describes about the Continuous Integration and the adoption of the continuous delivery which implies that the product can be delivered to the user at any time. He states that the continuous delivery has multiple stages that is used to check whether the software can be delivered to the user. In the study, the author found many issues, relations and solutions to the issues regarding the delivery is discussed. He says that the continuous and the on-time delivery makes benefits like faster feedbacks from the clients and the enhancement of the product. He concludes that the problems on delivery can be rectified by adopting the continuous delivery. Literature Analysis Summary The overall analysis of the articles related to the solution delivery and development says that the development and delivery has the relation. The development also affects the delivery stage. The development is the innovation or improvement of the technology which gets updated in daily life. The adoption of continuous delivery can overcome the issues involved in the on-time delivery. Current Practice on Solution Development and Delivery Recently agile development and delivery process is adopted for the solution. It minimizes risk involved in the development and delivery. Nowadays the use of mobile applications has been increased. The trends has been changed, so many companies has stopped promoting the websites and they started to develop their applications. Now cloud technology has been in practice because the user wants to focus on many different gadgets in one time. Internet of Things (IoT) technology is the recent one which is adopted by the companies. Everything has become user friendly. The things gets accessed from the place where we stay (Melendez, 2017). The efficiency of the delivery process has been increased in the recent practice. Many companies maintain Omni-channel fulfil method so that they easily deliver the products and services to their customers. The delivery process has been changed like delivery in a single day. Many online shopping websites has been keen on delivering the products to the custom ers on time (Lamer son, 2017). Comparison of Literature and the Current Practice The Literature of this assignment describes that the development is the changing trend in the Information Technology. The articles says that the development phase has to be focused on its values. The solution delivery has many issues enclosed with it. If the delivery gets delayed, it will ruin the entire project. The trends and practice gets changed in recent days. The development has made in our hands using the smart applications rule. More than the websites, the mobile applications has been in practice. Many companies focuses on faster or same day delivery and faster feedback from the customers. Conclusion The analysis on the solution development and delivery shows that the trends on it gets varied from years to years. At the early times, the development and delivery was a tedious task. The development process followed many models to develop a solution. Now the users use mobile applications and access many gadgets from the place where they stay. Literature review is explained and the current practice on the solution development and delivery is discussed. Comparison between the early and the recent practice is explained. References - Literature Chung, K., Park, J., Chin, S. and Chung, J. (2014). Study of Solution Development Methodology for Small-Size Projects.Information Technology Journal, 13(6), pp.1174-1179. Dingsyr, T. and Lassenius, C. (2016). Emerging themes in agile software development: Introduction to the special section on continuous value delivery.Information and Software Technology, 77, pp.56-60. Laukkanen, E., Itkonen, J. and Lassenius, C. (2017). Problems, causes and solutions when adopting continuous deliveryA systematic literature review.Information and Software Technology, 82, pp.55-79. Qureshi, S. (2009). Social and economic perspectives on the role of information and communication technology for development.Information Technology for Development, 15(1), pp.1-3. Lamerson, R. (2017).Last Mile Delivery Technology Trends | MHI Solutions. [online] Mhisolutionsmag.com. Available at: https://www.mhisolutionsmag.com/index.php/2016/12/16/last-mile-delivery-technology-trends/ [Accessed 5 Sep. 2017]. Melendez, C. (2017).Software development trends for 2017: Its all about the customer experience. [online] InfoWorld. Available at: https://www.infoworld.com/article/3148644/application-development/software-development-trends-for-2017-its-all-about-the-customer-experience.html [Accessed 5 Sep. 2017].

Donald Davidson Essays - Characters In Hamlet, Hamlet, Ghost

Donald Davidson In Shakespeare's Hamlet, there is a murder, and it doesn't say straight out who the murder is. There are no detectives on the case. No one within in the state is really questioning the murder of the King except for his son. It may not have all the customary qualities of detective story, but it does come across as a detective story in which Hamlet seeks to solve the mysterious death and to revenge for his father. In an ordinary, mundane, average crime the detectives try to figure out who the perpetrator or perpetrators are. This is not the case in Hamlet, the only evidence that comes across that the King was murdered was the ghostly figure who only appeared to be Hamlet's father. In scene five of act one, Horatio says to Hamlet after Hamlet talked to the ghost that ?These are but wild and whirling winds.? This questions the word of Hamlet by showing the he might be imagining things. Also, the new King and Hamlet's mother think he is mad. There may have even been a question in Hamlet's mind and that maybe why he delayed his revenge. This is where it appears to become a detective story. Hamlet has a hunch that his uncle, the new king, killed his father. Hamlet sets up a trap for the new king by watching his reaction to the play, which was based on the way the ghost told Hamlet he died. After that Hamlet may have had the final support to avenge his father's death. The motive for the new king to kill Hamlet's father was crystal clear. He married Hamlet's mother after only two months. He obviously also became the new king as well. Hamlet had that support early and he seemed the only one to being a detective. What made it seem more like a crime and a detective story was the way Claudius made his moves. He tried to cover up his action very cautiously. The king had Rosencrantz and Guildenstern over look Hamlet's ?transformation.? The king says in scene two of act two, so by your companies to draw him on to pleasures, and to gather so much as from occasion you may glean, whether aught to us unknown afflicts him thus that, open'd, lies within our remedy.? Hamlet does not make this easy for the king to get any information because he was either mad or acting mad, that's a decision that is up to the reader. There seemed to be two motives behind Hamlet's play as well. The first reason was to see the reaction of the king. The second was maybe to put doubt in other people in the state or bring up the question that his father may have been murdered. Hamlet is very sneaky and smart like a detective. Shakespeare's Hamlet may have not meant to be a detective story and certainly was different than the average one. Shakespeare puts a lot of questioning in this story. This seems to be a detective story, it can be questioned, but it does have the basic part of one. Hamlet plays the part of detective very well. There was a crime and there seemed to be a mystery to figure out. This is a well-written detective story that underlies a story about power, revenge, and deceit.

Albert Hofmann and the Invention of LSD

Albert Hofmann and the Invention of LSD LSD was first synthesized on November 16, 1938, by Swiss chemist Albert Hofmann in Sandoz Laboratories in Basle, Switzerland. However, it was a few years before Albert Hofmann realized what he had invented. LSD, known as LSD-25 or Lysergic Acid Diethylamide, is a psychoactive hallucinogenic drug. LSD-25 LSD-25 was the twenty-fifth compound developed during Albert Hofmanns study of amides of Lysergic acid, hence the name. LSD is considered a semi-synthetic chemical. The natural component of LSD-25 is lysergic acid, a type of ergot alkaloid that is naturally made by the ergot fungus, though a synthesizing process is necessary to create the drug. LSD was being developed by Sandoz Laboratories as a possible circulatory and respiratory stimulant. Other ergot alkaloids had been studied for medicinal purposes. For example, one ergot was used to induce childbirth. Discovery as a Hallucinogen It was not until 1943 that Albert Hofmann discovered the hallucinogenic properties of LSD. LSD has a chemical structure that is very similar to the neurotransmitter called serotonin. However, it is still not clear what produces all the effects of LSD. According to a Road Junky writer, Albert Hoffman deliberately dosed himself [after a milder accidental dose] with just 25 mg, an amount he didnt imagine would produce any effect. Hoffman got on his bicycle and rode home [from the Lab] and arrived in a state of panic. He felt he was losing his grip on sanity and could only think to ask for milk from the neighbors to counter the poisoning. Albert Hoffman's Trip Albert Hoffman wrote this about his LSD experience, Everything in the room spun around, and the familiar objects and pieces of furniture assumed grotesque, threatening forms. The lady next door, whom I scarcely recognized, brought me milk†¦ She was no longer Mrs. R., but rather a malevolent, insidious witch with a colored mask.† Sandoz Laboratories, the only company to manufacture and sell LSD, first marketed the drug in 1947 under the trade name Delysid. Legal Status It is legal to buy Lysergic acid in the U.S. However, it is illegal to process Lysergic acid into lysergic acid diethylamide, the psychoactive drug LSD.

Fast plant lab report Example | Topics and Well Written Essays - 1000 words

Fast plant - Lab Report Example The experiment was based on the general procedure as that of monohybrid activity. In this case the P1 and p2 plants are homozygous for two traits that include one dominant and one recessive. Four phenotypes were considered in this investigation of dihybrid genetics that include the following; Firstly, non-purple entails no expression of purple anthocyanin pigment in the plants (anthocyaninless) and the genotype of this mutant that is recessive is anl/anl. Secondly, Purple entails a pigment referred to as purple anthocyanin is visible on the hypocotyls. This trait is known to be wild type (dominant).The genotype is ANL/ANL Thirdly, the yellow Green; in this case, the homozygous (ygr/ygr) produces a plant that is light green than the normal green fast plant. Fourthly, normal green genotype is wild type (dominant) for yellow green and it is known as YGR. Purple stem Wilscon fast plants consists of anthocyanin which is purple pigment found in several plants that include Wisconsin fast pl ant used in the experiment (Williams, 1986). The pigment can be observed best at 4-7 days. This could be observed at the plant hypocotyls and stems under the leaf tips and cotyledons. It is well known that the single gene (anl) regulates whether the anthocyanin will be expressed or not. The (anl/anl) homozygous form is seen to be completely suppressed. In this case, the plant will appear bright green (non-purple).Yellow green gene (ygr) determines whether the leaves will be either green or yellow green in colour. The leaves will appear pale (yellow green in colour for recessive (ygr/ygr).But for YGR/YGR genotype the leaves will appear green and in this case, this genotype is the wild type. The test that is normally applied to show how well the observed ratios fit the expected statistical ratios is referred to as chi-square test. In this case, the observed number deviations is calculated from the

Talent Management in CDG a Boeing Company Essay

Talent Management in CDG a Boeing Company - Essay Example The researcher states that organizations are currently embracing Talent Management as a tool of attaining organizations goals and objectives. As such, Talent Management aids in attaining competitive advantage of organizations through production, addition of market value, and organization effectiveness. According to Rog, Talent Management is a significant factor, which determines the ability of the organization to acquire and retain essential talent successfully. Moreover, Talent Management in an organization establishes the extent of employee engagement in performance of various organization activities. Companies face workforce cost in the overall running of their business operations. As such, an effective analysis of the processes of recruiting and hiring employees provide insights and visibility of areas, which a company needs to improve. This is because maintenance of employees who have the capacity and potential to perform leads to improvement in the performance level of the comp any. According to Peter, companies have discovered that having the best talent enables them to have a competitive advantage in the global economy. Currently, there are few companies, which have a sufficient supply of talent. This depicts that talent has become a limited resource, which companies have to focus on managing effectively in order to attain success in their performance levels. Continental Data Graphics (CDG) a Boeing Company belongs to the aviation industry since the company deals with the provision of software and engineering solutions for defence and aerospace industries. As such, the company needs to have an effective Talent Management structure, which will enhance in attainment of competitive advantage. Bent (2011) argues that professionals within the aviation industry are declining substantially. This depicts that CDG Company needs to adopt an effective Talent Management strategy, which will enhance in attainment of success of the company. Sean and Kleiner (1999) pos tulates that benefits and compensation, development and training, and provision of incentives, which include medical coverage, are some of the needs of employees, which Talent Management in a company has to focus on satisfying. Therefore, this research will focus on identifying and evaluating the process of Talent Management in CDG Company. Further, the research will identify how CDG Company performs in the market of labour shortage due to various labour dynamics. 1.3 Research Objectives This research is governed by the following objectives: 1) To define Talent Management and Talent 2) To discuss the process of Talent Management 3) To discuss the advantages and disadvantages of Talent Management 4) To describe the current Talent Management Strategy of Boeing Company 5) To identify employee’s perceptions of Talent Management at Boeing Company 6) To propose improvement to Boeing Company current Talent Management Strategy 1.4 Research Questions This research is governed by the f ollowing research questions, which will aid in attaining objectives and aim of the research. 1) What is Talent Management

The Role of Homais in Madame Bovary

The Role of Homais in Madame Bovary Elixir for Decayed Corruption In Madame Bovary, Flaubert expresses the complications that give rise as a result of the unsatisfactory life of a young woman belonging to the socio-economic class. He directly introduces criticism of societys antics through many different characters in the novel, each of which play a significant role in delivering his message. One such character is Homais, an apothecary in the town of Yonville. Although this character appears to at first be a simply an insignificant, nosy character, his corrupt and self-serving nature continues to be revealed through his interactions with the people he meets. The purpose of Homais character in the novel is very direct as he represents the hypocritical and cowardly nature of the masculine middle class. His character also enables the society to behave in a corrupt fashion, supporting Flauberts interpretation of civilization as equally corrupt. Flaubert establishes Homais character in the novel as a device in delivering his criticism and ridicule of th e bourgeoisie and society as a whole during this time period. Initially, Homais character appears to act solely as a vehicle for Flauberts criticisms of the new, progressive middle class as cowardly and self serving. A significant manifestation of the corrupt and cowardly nature of Homais appears during a critical error he made causing the amputation of Hippolytes leg. Homais pretends that he wants to take rash actions to cure Hippolytes club foot purely for the benefit of Hippolyte, claiming that, its not for me. Its for you purely out of goodwill (174). However it is revealed that Homais simply wanted to use Hippolytes injury as a stepping stone for his flourishing in the journalism activity. Homais deceitful and sly nature appears as he attempts to convince Hippolyte by providing false hope of being more cheerful and agile and even hints that women would be more pleased after the procedure (174). Homais is essentially the catalyst for the downfall of Hippolyte by using him for his own benefit and becoming taken over by greed. Flaubert critic izes the nature of the middle class to only take action when benefit comes for them. He expands on the loss of human goodwill and shows the decay and corruption that replaces compassion and benevolence. This incident regarding Hippolyte also depicts the cowardly nature of the middle class in the face of confrontation. After the rapid decline of Hippolytes health, a different doctor was summoned in an attempt to find a cure for Hippolyte. The doctor begins the criticize Charles actions stating that he was an idiot who reduced an unfortunate man to such a state (180). He continues on to derail Charles character exclaiming that they load you down with remedies without worrying about the consequences(180). In the midst of the doctors condemnation of Charles, Homais does not defend Charles even though he was the propeller of the action and essentially lays down his dignity for his greater interests. Homais does not take responsibility for his actions and instead simply observes others ta ke the burden of the blame. His cowardly act manifests Flauberts interpretation of the nature of the middle class. Flaubert denounces how the priorities of the socio-economic class appears to be based on materialistic ideals rather than core human values such as dignity, pride, and honesty. Another incident that displays the corrupt self-serving nature of the middle class depicts by Flaubert is Homais treatment towards the blind beggar. Homais considers himself a cultured, intelligent, important man when in reality he is ultimately at the same level of the peasants and lower class he looks down on. Homais proceeds to regard the beggar with contempt describing him as a scrofulous infection and poses as an intelligent man by giving the beggar advice for his blind condition (280). A notable moment that exhibits the cowardly nature of Homais is the action he takes in retaliation to the blind beggar exposing the harmful actions Homais inflicts upon others in an attempt to add to his own benefit. Homais takes advantage of his resources to launch a secret campaign against the beggar, and ultimately succeeds in jailing the beggar in an asylum. His actions shows his resort to oppression of another mans civil liberties in an attempt to protect his own reputation. Homais character acts as a representation of the corrupt and cowardly aspects of the bourgeoisie. However, a depiction of Flauberts criticisms of society as a whole can be assumed to be an addition to the purpose behind the creation of Homais character. Ironically, Homais character is arguably one of the most corrupt in the novel, yet he is the only one who achieves his goal of social mobility. In comparison to characters who appear morally good such as Charles and Berthe Bovary who end up with tragic endings, Homais is able to achieve most if not all of his ambitions and goals. An example ofÂÂ   Homais success is the fact presented that he had just received the Legion of Honor (322). Flaubert presents this fact in a blunt style as the last line of the novel leaving a foul taste in the readers mouths. Homais achievement is not shown to be a beautiful event but rather a small gain in comparison to the corrupt actions he had taken leading up to his success. As a result, Flaubert criticizes society in its capitulation towards societys accolade to the most unethical figures. He condemns the mechanics behind society and essentially exposes the moral decay that is hidden underneath the gilded surface. Through Homais triumph in acquiring the Legion of Honor, Flaubert reveals the twisted nature of the mechanics behind society. He shows the disappointing reality that those who act in sly and immoral ways often times receive more benefit than those who live an honest life. Homais character depicts the segment of society through Flauberts perspective which prevents his evaluation from being truly objective. Moreover, Flaubert attempts to depict the raw corrupt nature of Homais character through a satirical argument between Homais and the priest: Yet, said Homais, it cant be both ways. Either she died in a state of grace (as the Church puts it), in which case she doesnt need prayers; or she died unrepentant (I believe thats the ecclesiastical term), and in that case- Bournisien interrupted, replying in an irritable tone that one needed to pray, no matter what. But, the pharmacist objected, since God knows all our needs, whats the use of prayer? What do you mean? asked the priest. Prayer! Arent you a Christian? I beg your pardon, said Homais. I admire Christianity. In the first place, it freed the slaves, introduced into the world a morality- Never mind about that! All the texts- Texts, bah! Open up the history books. We know they were falsified by the Jesuits. Charles came in and walked toward the bed. He drew the curtains back slowly. (305) In this piece of dialogue Homais engages in a argument with the priest about religion. This represents the clash in culture during the time between the new science ideas and the conservative ideas of centering life around religion. Homais continues to argue even in the presence of the deceased Emma Bovary. His disregard to the situation at hand shows how he doesnt appear to have any respect towards Madame Bovary. Flaubert creates the satirical conversation between Homais and Bournisien in order to reveal the hypocritical nature of Homais in asserting that he is a religious man but proceeding to denounce the essence of religion. He presents himself as a holy man yet he objects to the statement by the priest that prayer is needed no matter what. Homais claims to admire Christianity but advocates modern ideas including Voltaire and science. Through the dialogue, Homais character is seen once more in negative light as a representation of the middle class. The insensitivity of Homais to t he environment of the deceased is reflected in his insistence in continuing to partake in the squabble with the priest. Homais interrupts and blurts out his own uneducated ideas without giving consideration to the priests words. Another characteristic revealed is in how he disregards the dead in order to win the argument and therefore feel a sense of self-superiority. The childish antics performed by Homais shows the twisted order in his priorities to favor self over the traditional values of respect. As a result of Homais corruption, the moral decay has reached such a deep point in his character that he supports Flauberts intent in depicting the middle class as well as society. Finally, Madame Bovary brings to light Flauberts dissection of society as corrupt and immoral through the character Homais. Throughout the novel Homais perpetrates many unethical actions that displays the mechanics of society through a single person. He reveals his cowardly and corrupt actions which supports the conclusion that his character was essentially devised to be used as a device for Flauberts heavy condemnation towards civilization. The novel also paves way into Flauberts analysis of a specific group, the bourgeoisie, to be equally Madame Bovary reveals the actions that give rise to the decay within the community. Through this manifestation, Flaubert delivers his denunciation of society and the middle class to be impure.

Ch 18

Chapter 18 Ethers & Epoxides; Thiols and Sulfides Assigned Reading from McMurry: Read Sections 18. 1 through 18. 9; not responsible for â€Å"Focus on †¦ Epoxy Resins & Adhesives, pp. 697-698). Recommended Problems from McMurry: 18. 1a-e;18. 18. 2;18. 3a-d; 18. 4; 18. 5a-d; 18. 6a-b; 18. 7a-b; 18. 8; 18. 9; 18. 10; 18. 11; 18. 12a,b; 18. 13a,b; 18. 14a-c; 18. 16a-f; 18. 17; 18. 18; 18. 19a-c; 18. 20; 18. 21; 18. 22; 18. 23a-e; 18. 24a-I; 18. 25a-f; 18. 26a-d; 18. 27; 18. 28; 18. 29ad; 18. 30a-e; 18. 31; 18. 32; 18. 33; 18. 34; 18. 35a-d; 18. 36; 18. 37; 18. 38; 18. 39; 18. 40a,b; 18. 41a-d; 18. 2; 18. 43; 18. 44; 18. 45; 18. 45; 18. 46; 18. 47; 18. 48; 18. 49; 18. 51; 18. 52; 18. 53; 18. 54; 18. 551-e; 18. 56; 18. 57; 18. 58a-b; 18. 59a-b; 18. 60; 18. 61. 18. 1 Names and Properties of Ethers Method A: Simple ethers; alphabetize if two organic substituents. CH3–CH2–O–CH2–CH3 Diethyl ether Methyl propyl ether O CH3–CH2–CH2–O œCH3 CH3 Methyl phenyl ether SP 18. 01 Provide systematic names for the following ethers. CH3–CH2–O–CH2–CH2–CH2–CH3 O SP 18. 02 Provide structures for the following systematic names. Systematic name: Isopropyl phenyl ether Systematic name: Cyclohexyl ethyl etherMethod B: Other functional groups present, ether component is an â€Å"alkoxy† substituent. Alkoxy examples: methoxy -OCH3, ethoxy -OCH2CH3, propoxy -OCH2CH2CH3, etc. O C H3 O CH3 O C H3 para-Dimethoxybenzene 3-Methoxy-1-cyclopentene SP 18. 03 Provide systematic names for the following complex ethers. OCH3 O CH2CH3 Cl SP 18. 04 Provide structures for the following systematic names. Systematic name: meta-Bromopropoxybenzene Systematic name: 1-Isopropoxycyclopentene 18. 2 Synthesis of Ethers The Williamson Ether Synthesis R + O an alkoxide C X R SN2 an alkyl halide methyl & 1o best; X = Cl, Br, I, OTos O C ether productExample: O Na + Sodium phenoxide CH3 Br O CH3 Phenyl methyl e ther (anisole) + Na Br + X SP 18. 05 Complete the following reactions. CH3 CH3 C O Na + CH3 I + Na I CH3 CH3 CH3 C CH3 I + Na O CH3 + Na I SP 18. 06 Provide the suitable alkoxide and alkyl halide necessary to produce 2-ethoxy-2-methyl butane in good yield. CH3 CH3 CH2 C O CH3 CH2 CH3 + Na Br 8. 4 Oxymercuration Intermediates †¢ For laboratory-scale hydration of an alkene †¢ †¢ Use mercuric acetate in THF followed by sodium borohydride Markovnikov orientation – via mercurinium ion Alkoxymercuration of Alkenes General Reaction: R C C 2) NaBH4 H C R EtherAlkene RO Step #1 RO C 1) Hg(OAc)2, ROH H g OA c C C Step #2 R + HOAc Markovnikov addition SP 18. 07 Complete the following reactions by displaying the final major organic product. H C 1) Hg(OAc)2, CH3OH H C 2) NaBH4 H CH3 CH3 C C H CH3 1) Hg(OAc)2, CH3OH 2) NaBH4 SP 18. 08 Specify the alkene and alcohol needed to produce the following ether. Alcohol OCH2CH3 1) Hg(OAc)2, CH3 2) NaBH4 Alkene 18. 3 Reactions of Ethe rs: Acidic Ether Cleavage General Reaction: HX C O C C OH + X C (strong acid) Ether Alcohol Alkyl halide SP 18. 09 Predict the product for the following ether-cleavage reaction. CH3 CH3 C O CH3 HBr CH2CH3 8. 4 Reactions of Ethers: Claisen Rearrangement O OH 1,3 O to C shift Thermodynamically more stable o 250 Allyl phenyl ether C9H10O ortho-Allyl phenol C9H10O Mechanism (involves six-membered transition state): 1 O TS 2 3 1 O 2 H keto-enol tautomerization 3 O H SP 18. 10 Predict the structure for the following Claisen rearrangement. O o 250 2-Butenyl phenyl ether C10H12O 18. 5 Cyclic Ethers: Epoxides (2 methods) General Reaction 1: O C C + R Alkene C O O O O C H A peracid C An epoxide R C O A carboxylic acid Specific Example 1: O Cl C O O H m-CPBA o H O O + CH2Cl2, 25 C H 1,2-Epoxycycloheptane Cl H C O H 18. Cyclic Ethers: Epoxides (2 methods) General Reaction 2: C OH X2, H2O C C C X A halohydrin Alkene O NaOH H2O C + H2O + NaX C An epoxide Review Section 7. 3 Specific Example 2: H CH3 C C H CH3 cis-2-Butene Br2 H2O H CH3 Br C OH C H CH3 NaOH H2O O HC CH3 C H + H2O + NaBr CH3 meso-2,3-Dimethyl-oxirane (or cis-2,3-epoxybutane) SP 18. 11 Fill in the appropriate intermediates showing the correct stereochemistry. H CH3 C C CH3 Br2 NaOH H H2O H2O trans-2-Butene + H2O + NaBr 18. 6 Reactions of Epoxides: Ring-Opening General epoxide structure: O C Since each atom is sp3 there is considerable angle strain in the epoxide ring-system.C Acidic Conditions: Epoxide opening under acidic conditions (aqueous acid) yields 1,2-diols General Reaction: H H O O C H C HO C H2O An epoxide C OH A 1,2-diol (glycol) H O C H C + O H H O C + C H O H H O H Specific Example (using symmetrical epoxide): H + H H3O OH H2O OH O H H trans-1,2-Cyclohexanediol SP 18. 12 Predict the correct structure of the product diol showing the correct stereochemistry. O H CH3 C C CH3 H trans-2,3-epoxybutane H3O+ H2O Note: Epoxide opening under anhydrous acidic conditions yields halohydrins. Specific Example ( 2 ° and 1 ° carbons): o 1 carbon o 2 carbon O CH3 H C C H H 1,2-EpoxypropaneOH HCl Et2O CH3 C Cl CH2 Cl + CH3 H 1-Chloro-2-propanol (90%) C CH2 OH H 2-Chloro-1-propanol (10%) SP 18. 13 Using the above model predict the major halohydrin. O H C H C HCl H Et2O O H C C H H HCl OH C Et2O H Cl CH2 Cl + C CH2 OH H Explanation: In cases where a 2 ° carbon and a 1 ° carbon form the epoxide ring, the major halohydrin product will be the one where the incipient alcohol is 2 ° and the halide is 1 °. Upon protonation of the epoxide oxygen the halide ion simple attacks the less-hindered 1 ° carbon with a greater frequency to give the major regioisomer. Specific Example (3 ° and 1 ° carbons): SP 18. 4 Using the above model predict the major halohydrin. Circle one. O C C H H HCl OH C Et2O + C H Cl Cl H C OH C H H Explanation: In cases where a 3 ° carbon and a 1 ° carbon form the epoxide ring, the major halohydrin product will be the one where the incipient alcohol is 1 ° and the halide is 3 °. Upon protonation of the epoxide oxygen the halogen attacks the more-stabilized (same as moresubstituted) carbon atom to give the major regioisomer described. Basic Conditions: Note: Nucleophile will always attack least-hindered position. Specific Example: o 3 carbon 1o carbon O CH3 CH3 C C H H OH NaOH H2O, ? CH3 C CH2 OH CH3 -Methyl-1,2-propanediol SP 18. 15 Predict the structure of the 1,2-diol from the following reaction. O C C H H NaOH H2O, ? Reaction with Grignard Reagents: O CH3 CH3 C C H H OH 1) CH3CH2MgBr, Et2O 2) (aq) NH4Cl CH3 C CH2 CH3 CH2 CH3 SP 18. 16 Predict the structure of the organic product from the following Grignardepoxide reaction. O H C C H H 1) CH3MgBr, Et2O 2) (aq) NH4Cl Reaction with a 1 ° amine: O H C OH CH2 H H2NCH2CH2CH3 C CH2 N CH2 CH2 H Reaction with a 2 ° amine: O H C OH H H3C CH2 + N H3C H C CH2 N CH3 CH3 CH3 SP 18. 17 Predict the structure of the epoxide and amine needed to generate the amino alcohol shown to the right.OH + C H3 C CH3 Epoxide Amine CH2 N H 18. 7 Crown Ethers †¢ Large rings consisting of repeating (-OCH2CH2-) or similar units †¢ Named as x-crown-y – x is the total number of atoms in the ring – y is the number of oxygen atoms – 18-crown-6 ether: 18-membered ring containing 6 oxygen atoms †¢ Central cavity is electronegative and attracts cations 18. 8 Thiols and Sulfides †¢ Thiols (RSH), are sulfur analogues of alcohols – Named with the suffix -thiol – SH group is called â€Å"mercapto group† (â€Å"capturer of mercury†) Thiols: Formation and Reaction †¢ From alkyl halides by displacement with a sulfur nucleophile such as –SH The alkylthiol product can undergo further reaction with the alkyl halide to give a symmetrical sulfide, giving a poorer yield of the thiol Sulfides †¢ Sulfides (RSR? ), are sulfur analogues of ethers – Named by rules used for ethers, with sulfide in place of ether for simple c ompounds and alkylthio in place of alkoxy Using Thiourea to Form Alkylthiols †¢ Thiols can undergo further reaction with the alkyl halide to give dialkyl sulfides †¢ For a pure alkylthiol use thiourea (NH2(C=S)NH2) as the nucleophile †¢ This gives an intermediate alkylisothiourea salt, which is hydrolyzed cleanly to the alkyl thiourea Oxidation of Thiols to Disulfides Reaction of an alkyl thiol (RSH) with bromine or iodine gives a disulfide (RSSR) †¢ The thiol is oxidized in the process and the halogen is reduced Sulfides †¢ Thiolates (RS? ) are formed by the reaction of a thiol with a base †¢ Thiolates react with primary or secondary alkyl halide to give sulfides (RSR’) †¢ Thiolates are excellent nucleophiles and react with many electrophiles Sulfides as Nucleophiles †¢ Sulfur compounds are more nucleophilic than their oxygen-compound analogues – 3p valence electrons (on S) are less tightly held than 2p electrons (on O) †¢ Sulfides react with primary alkyl halides (SN2) to give rialkylsulfonium salts (R3S+) Oxidation of Sulfides †¢ Sulfides are easily oxidized with H2O2 to the sulfoxide (R2SO) †¢ Oxidation of a sulfoxide with a peroxyacid yields a sulfone (R2SO2) †¢ Dimethyl sulfoxide (DMSO) is often used as a polar aprotic solvent 18. 9 Spectroscopy of Ethers †¢ Infrared: C–O single-bond stretching 1050 to 1150 cm? 1 overlaps many other absorptions. †¢ Proton NMR: H on a C next to ether O is shifted downfield to ? 3. 4 to ? 4. 5 – The 1H NMR spectrum of dipropyl ether shows this signal at ? 3. 4 – In epoxides, these H’s absorb at ? 2. 5 to ? 3. 5 in their 1H NMR spectra Carbon NMR: C’s in ethers exhibit a downfield shift to ? 50 to ? 80 Let’s Work a Problem When 2-methyl-2,5-pentanediol is treated with sulfuric acid, dehydration occurs and 2,2dimethyltetrahydrofuran is formed. Suggest a mechanism for this reaction. Which of the two ox ygen atoms is most likely to be eliminated and why? Answer First, there is protonation of the 3? –OH group, then a 3? carbocation is formed via loss of H2O. Then there is a nucleophilic attack of the carbocation by the 2nd –OH group. The 3? OH group is the one eliminated in all likelihood because its removal involves the formation of the more stable 3? carbocation.