Phosphorus-Boron and Phosphorus-Silicon Ring Systems Functionalization of Phosphorus Ring Systems

Abstract The diphosphide K2[(t-Bu)P-BN(i-Pr)2-P(t-Bu)] reacts with t-BuPCl2 to form the P3B ring system (i-Pr)2NB(t-BuP)3 1. The five-membered P4B ring system (i-Pr)2NB(t-BuP)4 2 is formed from K2[(t-BuP)4] 3 and (i-Pr)2NBCl2 analogous to the above reaction. The reaction of 3 with SiCl4 or Si2Cl6 produces the novel five-membered ring systems (t-BuP)4SiCl2 4 or (t-BuP)4Si(Cl)SiCl3 5 respectively. New routes to the synthesis of the monofunctionalized cyclophosphanes (t-BuP)2PCl 6 and (t-BuP)3PCl 7 and to the new bifunctionalized cyclophosphane 1-Br-3-[(t-Bu)(Br)P]-2.4-(t-Bu)2-P4 8 will be reported. 1, 2, 4, and 7 could be characterized by X-ray structure analysis; the structures of 5 and 8 could be inferred from NMR data. The 31P NMR spectra of 2 and 7 indicate (10,11B) and (35,37Cl) isotopic shifts respectively.