The addition of 2, 4-dinitrobenzenesulfenyl chloride (ArSCl) to a number of phenylmethylenecyclopropanes (2, 3, 4) and to α-cyclopropylstyrene (5), in CH2Cl2 and AcOH, has been investigated. The participation of the cyclopropylcarbinyl-phenyl carbonium ions (19a, 19b, 20, 22) is assumed. The attachment of the electronegative 2, 4- dinitrobenzenesulfenyl group on the cyclopropyl ring prevents rearrangement with ring ...