摘要:
Reaction of Rh(PCy(3))(2)Cl (4a, Cy = cyclo-C6H11 with the phosphacumulenes Mes*P=C=X (X = O (1) X = NPh (2); Mes* = 2,4,6-(t-Bu)(3)C6H2) results in P=C bond cleavage to form [2,4-(t-Bu)(2)C6H2(6-CMe(2)CH(2)PH)](5) and trans-Rh(PCy(3))(2)Cl(CX) (6, X = O; 7,X = NPh), respectively. In contrast, 4a and related Rh(I) PPh(3) complexes are catalyst precursors for the rearrangement of Mes*P=C=CPh(2) 13) to its isomer [2,4-(t-Bu)(2)C6H2(6-CMe(2)CH(2)PCH=CPh(2))] (8); the intermediate [Rh(PCy(3))[eta(2)(P,C)-Mes*P=C=CPh(2)]Cl](n) (9a), which is itself an active catalyst for the isomerization, was isolated and characterized spectroscopically.