Synthesis and structures of the 1,3-diphospha-2-metallapentanes [LnM{P(Ph)C6H4PPh}][MLn= ZrCp″2(2), rac-SnR2(3), SnMe2, or BAr; Cp″=η-C5H3(SiMe3)2-1,3, R = CH(SiMe3)2, Ar = C6H2But3-2,4,6]; X-ray structures of complexes (2) and (3)
Abstract
Reactions of LnMCl2 with 1,2-C6H4(PPh)2[Li(tmeda)]2 yield the metallacycles [Ln[graphic omitted]Ph}][MLn= ZrCp″2(2), rac-SnR2(3), meso-(4a) and rac-(4b) SnMe2, and BAr (5); tmeda =(Me2NCH2)2, p″=η-C5H3(SiMe3)2-1,3; R = CH(SiMe3)2, Ar = C6H2But3-2,4,6], complex (2)[unlike (3)] having distinct P environments in the crystal, P(1) being planar and P(2) pyramidal and Zr–P(1) < Zr–P(2); in C6D5CD3 solution, the low temperature PMPCC skeletal arrangement in (2) and (5) corresponds to that of crystalline (2), with exchange processes being evident at higher temperatures [also noted for (3)].