Abstract

BRAVO1,*, José A.  and  VILA², José L.. Synthesis of alkenes: Claisen rearrangement of allyl vinyl ethers, part III; Mechanistic views; The organic chemistry notebook series, a didactical approach, N ° 11. Rev. Bol. Quim [online]. 2016, vol.33, n.3, pp.127-133. ISSN 0250-5460.

Abstract This is the eleventh 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. We have taken a series of reactions compiled 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. In chapter 11, we expose a complementing of Claisen rearrangements of ally-vinyl ethers started two papers ago. Now it's turn for the use of a variation of the Claisen rearrangement: the ester-enolate variation (also known as the ketene acetal variation). In this sense, the synthesis of the natural product: methyl santolinate is briefly exposed in a mechanistic manner. Also, the mechanism of the synthesis of unsaturated amino acid derivative and ulterior lactone hydrochloride from the Z-crotyl glicine ester is proposed on the basis of theoretical approaches. The condensation between allylic alcohols and cyclic orthoesters to produce (via Claisen rearrangement) lactones with the inverted allyl group as a substituent is mechanistically exposed. Vinyl lactones can be converted into cycloalkenes (via Claisen rearrangement of cyclic enol ethers); we've analyzed the mechanism.

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

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