An Efficient Substrate-Induced Method for the Synthesis of CF3-Substituted Cyclopropanes by Metal-Free Reaction of Trifluoromethyl Styrylisoxazoles with Nitromethane

A series of (trifluoromethyl)cyclopropanes (TFCPs) tolerating a broad range of functional groups, known as tert-butyl bioisosteres, have been obtained from the cyclization reaction between nitromethane­ and 5-[β-(trifluoromethyl)styryl]isoxazoles in 70–94% yields and 75:25 to 90:10 dr. This method offers practical access to this cyclopropyl moiety of pharmacological interest, employing an inorganic base under phase-transfer conditions.