Transformations of resin-bound pyridinium ylides: I. A stereoselective synthesis of 2,2,3-trisubstituted cyclopropanecarboxylates

Article abstract of DOI:10.1016/S0040-4039(97)10081-8

Trans-3-alkyl- or -arylcyclopropanecarboxylates, substituted in the 2-position with alkoxycarbonyl or nitrile groups, are efficiently prepared by coupling bromoacetic acid with Wang resin followed by pyridinium ylide formation and condensation of the ylide with ethylidene malonate derivatives. Good yields are obtained after cleaving the resin and esterifying the resulting cyclopropanecarboxylic acid with diazomethane.