The regio-and stereoselective photoinduced addition of N-carbomethoxymethylpyrrolidine to 5 (S)-tert-butyldimethylsiloxymethyl-furan-2 (5H)-one in the presence of benzophenone yields 3 (R)-[N-(diphenylhydroxymethyl) carbo methoxymethylpyrrolidin-2′-yl]-4 (S)-tert- ...