Abstract

BRAVO¹, José A.  and  VILA, José L.. Synthesis of alkenes: claisen rearrangement of allyl vinyl ethers, part i; mechanistic views; the organic chemistry notebook series, a didactical approach, N2 9. Rev. Bol. Quim [online]. 2016, vol.33, n.1, pp.27-33. ISSN 0250-5460.

We present now the ninth theoretical assay in the series: "The Organic Chemistry Notebook Series, a Didactical Approach". The aim of this series of studies is to help students to have a graphical view of organic synthesis reactions of diverse nature. In the present chapter, we board the fascinating thematic on Claisen rearrangements of ally-vinyl ethers as a way to obtain alkenes. Starting from allyl alcohols by rearrangements of the corresponding derivative allyl vinyl ether it is feasible the obtaining of carbonyl compounds unsaturated at the positions: yS; these include aldehydes, ketones, esters and amides. We have assayed theoretical mechanisms for the conversion of allyl alcohol into allyl vinyl ether. The synthesis of the insect pheromone: 3,7-dimethyl-2,6-decadiene-1,10-diol from allyl alcohol and methyl orthoacetate is mechanistically reviewed. The formation of j^unsaturated N,N-dimethyl amides is mechanistically discussed. To end the part I of this series on synthesis of alkenes by Claisen rearrangement of allyl vinyl ethers, we study a feasible mechanism of an alternative to the acidic and heated process involved in the synthesis of the j#unsaturated carbonyl compounds: the Claisen rearrangement of lithium enolates, or the trimethyl or the t-butyl dimethylsilyl enol ethers. We have taken a series of reactions reviewed by W. Carruthers in 'Some modern methods of organic synthesis', and we have proposed didactical and mechanistic views for them. This theme is included in the chapter "Formation of carbon-carbon double bonds" in the mentioned text.

Keywords : Organic Chemistry; Alkenes; Allyl vinyl ethers; Claisen rearrangment; Mechanisms of Reactions; W. Carruthers.

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