CAN AN AROMATIC RING ALTER THE REACTIONS OF A NEARBY UNSATURATED IMIDE - A STUDY OF THE RATE AND SELECTIVITY OF NITRILE OXIDE CYCLOADDITIONREACTIONS OF ACRYLOYL DERIVATIVES OF THE REBEK IMIDE BENZOXAZOLE

Cycloadditions of acryloyl derivatives of the Rebek imide benzoxazole are extraordinarily stereoselective, but have rates and regioselectivi ties that otherwise parallel those of a simple achiral model. It appea rs that the benzoxazole ring of these compounds completely shields the inner face of the nearby alkene, but has no measurable effect on the rate of reactions on the outer face. (C) 1997, Elsevier Science Ltd.