THE INFLUENCE OF SUBSTITUENTS ON THE PHOTOCHEMICAL GENERATION AND STABILITY OF 2-MORPHOLINOCYCLOPROPANOLS

By irradiation in oxygen-free ether alpha- or beta-substituted beta-mo rpholinopropiophenones 1a-c form the corresponding cyclopropanols 2 wi th 1-aryl and 2-morpholino group in a relative cis-configuration in hi gh yields. The photocyclization of pure 1a-c enantiomers proceeds enan tioselectively under these conditions. In methanol and presence of oxy gen electronically excited 1c-h are converted to enaminones 3c-h via o xidation of intermediate cyclopropanols 2c-h. In the presence of elect ron-acceptor molecules this reaction apparently follows a SET mechanis m.