Cyclopropanation with t-butylsulfonyl methyllithium

Terminal alkenes and cyclic 1,2-disubstituted alkenes were cyclopropanated [473] in excellent yield with the title reagent under catalysis by Ni(acac)2 (Table 4.6). The reagent was generated in situ by 

Other a-sulfonyl carbanions, t-BuS02CHR2Li and t-BuS02CMe2Li, have also been successfully used [474]. 

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