Menthyl-p-toluenesulfinate

An a-fluorinated phosphinyl sulfoxide derivative, prepared as a mixture of diastereomers by the treatment of lithiated (a-fluoromethyl)diphenylphosphine oxide with menthyl p-toluenesulfinate, has been used for the preparation of enan-tiomerically pure 1-fluorovinyl and 1-fluoromethyl sulfoxides [76]. (E)-Diethyl ferf-butylsulfinylmethylphosphonate 117 has been prepared by the sulfinylation... 

A reaction similar to that discussed above occurs between 2 equivalents of the sulfoxide carbanion 44 and diastereomerically pure menthyl p-toluenesulfinate 45 and results in the formation of optically active disulfoxide 46 and starting sulfoxide 44 (71). 

Menthyl p-toluenesulfinate 45, a key compound in the stereospecific synthesis of sulfoxides, was also found to be a very convenient starting material for chiral sulfinamides. Montanari... 

The preparation of (S)-(-)-menthyl p-toluenesulfinate described in Part A is based upon the procedure reported by Solladie. 2-Bromo-2-cyclopentenone ethylene ketal is available from 2-cyclopentenone by the procedure of Smith and co-workers. The present procedure has been used by the submitters to prepared analogous chiral ci-sulf1nyl a,B-enones (Table I).11 The utility of these chiral synthons is enhanced by their stability, the facility of their... 

A quite general method of access to optically pure sulfoxides is due to Andersen [96-98] a menthyl sulfinate ester is reacted with a Grignard reagent. Both enantiomers of menthyl p-toluenesulfinate are commercially available. A large-scale preparation of (-)-menthyl (S)-p-toluenesulfinate as well as that of (7 )-(+)-methyl p-tolyl sulfoxide is described [99] by Solladi et al. Other related approaches are presented and discussed in [86]. 

Diethoxytriphenylphosphorane, 109 Diisobutylaluminum hydride, 115 Diphosphorus tetraiodide, 127 Hexamethylphosphoric triamide, 142 (S)-( - )-Menthyl p-toluenesulfinate, 173... 

P-HYDROXY ESTERS Aceto(cprbonyl)cyclo-pentadienyl(triphenylphosphine)iron. (S)-(—)-Menthyl p-toluenesulfinate. y-HYDROXY esters Titaniurh(IV) chloride. (x-HYDROXY- P-keto ESTERS Lithium diiso-propylamide. 

The reagent is obtained by reaction of (S)-( - )-menthyl p-toluenesulfinate (10, 405) with a-lithio-N,N-dimethylacetamide (83% yield). 

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