MACROCYCLES CONTAINING BICYCLOPHOSPHORANE MOIETIES

The first stable macrocycles, 12-15, 16, 18, and 23, containing pentac ovalent phosphorus have been obtained by an Atherton-Todd reaction bet ween the bis(hydridobicyclophosphoranes) 3-7 and the corresponding bin ucleophile HO-(CH2)2-X-(CH2)2-OH. The tricyclic monophosphoranes 8-11 as well as the noncyclic derivative 20 have also been isolated. A path way that accounts for the formation of all these compounds is proposed . The X-ray crystal study of two 16-membered rings, 14, 15, confirms t he diequatorial placement of the macrocyclic frame on the trigonal bip yramidal phosphorus which retains the most favorable axial-equatorial- axial annelation of the bicyclic moiety. Comparison of these two molec ular structures points out the effect of the nature of X on the confor mation of the macrocycle.