Structure of a syn-aldol addition product of benzaldehyde and a prolinol-derived O-silacyclopentyl ketene N,O-acetal

摘要

The compound (5S,6S,11aS)-hexahydro-6-methyl-5-\udphenylspiro[l H,7 H-pyrrolo[2,l-e][l,3,6,2]dioxazasilonine-\ud3,1'-silacyclopentan]-7-one (1) results from the\udsilicon-directed condensation of the prolinol-derived O-silacyclopentyl ketene N,O-acetal (2) with benzaldehyde.\udThe five-membered pyrrolidine ring has an envelope conformation and the silacyclopentyl ring has an en-type conformation with C17 and C18 on opposite sides of the C16-Si-C19 plane. Both of these rings appear to be disordered.