Smith synthesis

In the first of these sequences, often called the Torgov-Smith synthesis, the initial step consists in condensation of a 2-alkyl-cyclopentane-l,3-dione with the allyl alcohol obtained from 6-methoxy-l-tetralone and vinylmagnesium chloride. Although this reaction at first sight resembles a classic SN displacement, the reaction is actually carried out with only a trace of base. 

M For a review of the reactions of epoxides, see Smith Synthesis 1984, 629-656. For a review of their synthesis and reactions, see Bartdk Ling, in Patai The Chemistry of Functional Groups, Supplement Wiley New York, 1980, pp. 609-681. 

In the three different approaches envisaged for the total syntheses of rhazinilam, the construction of the pyrrole ring was operated in two different manners a Knorr-type reaction in the Smith synthesis and a 1,5-electrocyclization of an allyl-iminium compound in the Sames and Magnus syntheses. 

For a review on epoxide chemistry, see J. Gorzynski Smith, Synthesis, 1984, 629. 

Jorgensen et al. found that reduction of an allylic alcohol by lithium aluminum hydride can be carried beyond the stage of the saturated alcohol to give a cyclopropane. Thus a cinnamyl acid, ester, aldehyde, or ketone on reduction with 100% excess LiAlHj in refluxing tetrahydrofurane or dimethoxyethane affords a phenyl-cyclopropane in yield of 45-80%. The reaction complements the Simmons-Smith synthesis. 

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