CONTRIBUTIONS TO THE CHEMISTRY OF PHOSPHORUS .210. PENTAORGANYLTRICYCLONONAPHOSPHANES WITH A STRUCTURE ANALOGOUS TO BREXANE, B-P9ME5, B-P9ET5, B-P9IPR5

The reaction of RPCl2, P4, and magnesium provides two constitutionally isomeric pentaorganyltricyclononaphosphanes. Besides the isomer with a P9 skeleton analogous to that of noradamantane (a-P9R5), which was already identified, a further isomer of lower relative abundance (b-P9R5) has now been found. In the case of R = Et (2) it has been isolated as a pale yellow, oily liquid and, in the cases of R = Me (1) and iPr (3), has been highly enriched. According to their P-31{H-1}-NMR spectra, 1-3 have a constitution analogous to that of the hydrocarbon brexane, thus being 2,4,5,8,9-pentaorganyltricyclo[4.3.0.0(3.7)]nonaphosphanes. They are each formed as mixtures of several configurational isomers, which differ in their relative arrangements of the organyl groups.