CONFORMATIONS OF PLATINACYCLOHEXANES - NMR-STUDIES AND CRYSTAL-STRUCTURES OF [PT(CH2)4CH2(PPHME2)2] AND [PTCH2CH2CME2CH2CH2(PPHME2)2]

The platinacyclohexanes Pt(CH2CH2CR′R″CH2CH2)(PR3)2] where R3 = Ph3 (a) or Me2Ph (b) and R′ = R″ = H (1a,b), R′ = H, R″ = Me, R3 = Ph3 (2), or R′ = R″ = Me (3a,b) have been prepared. Variable temperature 1H31P (400 MHz) and 13C1H (100 MHz) NMR studies reveal that ring reversal is rapid even at -150°C. The X-ray crystal structures of compounds 1b and 3b have been determined; in 1b the ring has the half-chair form, while in 3b it is in the skew conformation. © 1990.