MOLECULAR-STRUCTURES OF NOVEL MACROCYCLES CONTAINING BIS(BICYCLOPHOSPHORANES)

Single crystal X-ray diffraction studies of the macrocyclic bis(bicycl ophosphoranes), [N(CH2CMe2O)(2)PO2](2)[(CH2)(2)O(CH2)(2)] [(CH2)(2)S(C H2)(2)] (1) [N(CH2CMe2O)(2)PO2](2)[(CH2)(2) NPh(CH2)(2)][(CH2)(2)N-t-B u(CH2)(2)] (2), revealed trigonal bipyramidal structures at the phosph orus atom. A comparison is made with the structures of related bicycli c phosphoranes containing similar ring systems that comprise both satu rated (1-4) and unsaturated (5-8) members, A molecular mechanics treat ment is performed which shows close agreement between the calculated a nd X-ray structures of 1 and 2.