3-Methylcyclohexene, from 2-methylcyclohexanone tosylhydrazone

The Shapiro reaction1 is the conversion of arylsulfonylhydrazones to alkenes via treatment with alkyllithium reagents or alkali metal amides.2,3,4,5 The reactions proceed via alkenyllithium intermediates, which can be transformed to the alkene upon protonation or can be captured with other electrophilic reagents. For example, the tosylhydrazone 1 derived from 2-methylcyclohexanone was converted to 3-methylcyclohexene (2) in 98% yield upon treatment with two equivalents of butyllithium.1... 

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