[OSH4(PPH(3))(3)] - NEW CATALYST FOR THE SELECTIVE CYCLOPROPANATION OF ACTIVATED OLEFINS

The title compound was found to be an efficient catalyst for the selec tive cyclopropanation of activated olefins by ethyl diazoacetate. The cyclopropane yields range from moderate to good (75 to 95%) for activa ted olefins such as styrene and styrene derivatives, but are rather lo w (20 to 30%) for non-activated olefins such as terminal and cyclic al kenes. In the intermolecular competition, styrene was 45 times more re active than cyclooctene. In all cases, trans (exo) cyclopropane predom inated over the cis (endo) isomer.