Silicon in Organic Synthesis. 24. Preparation and Selected Reactions of Functionalized 1-(Trimethylsilyl)-Substituted Cyclopropanes

Article abstract of DOI:10.1021/jo00193a030

Several methods for preparing bifunctional 1-(trimethylsilyl)-substituted cyclopropanes are described.The methyl bromide 4, available by Simmons-Smith cyclopropanation of 2 and bromination with phosphorus tribromide, is shown to be highly reactive to S_N2 displacement and therefore easily transformed into a variety of other derivatives including the phenyl sulfide, phenyl sulfone, nitrile, and phenyl selenide.Ring-closure protocols have been applied to gain access to the triphenylphosphonium salt, phosphonate ester, and carboxaldehyde (22).The dimethyl acetal 23 ofthis aldehyde gives every indication of being an excellent conjunctive reagent as exemplified by its conversion to 24, 26, and 30.Reactive anions of type A (X = SO2Ph, SPh, SePh, CN) have been generated and in certain cases utilized for additional chemical transformations.