N, N-Dialkylamide der 2-Hydroxy-2-phenyl-cyclopropan-1-carbonsäure - photochemische Darstellung und Strukturuntersuchung

N,N-Dialkylamides of 2-Hydroxy-2-phenyl-cyclopropan-1-carboxylic Acid – Photochemical Synthesis and Determination of the Structure Irradiation of N,N-dialkylamides of β-benzoylpropionic acid 2a, b in ether by n,π*-excitation leads to the corresponding amides of the hitherto unknown 2-hydroxy-2-phenyl-cyclo-propancarboxylic acid 3a, b, 4a, b. The photocyclization yields diastereomeric mixtures E:Z = 2.5–3:1. The determination of the relative configurations is based on the different tendency of dimerization of the E and Z diastereomers.