om981023d_si_001.pdf (874.01 kB)

Metal Ion Mediated Transfer and Cleavage of Diaminocarbene Ligands

Download (874.01 kB)
journal contribution
posted on 06.05.1999, 00:00 by Rong-Zhi Ku, Jen-Chung Huang, Jian-Yang Cho, Fu-Mei Kiang, K. Rajender Reddy, Yi-Chun Chen, Kuo-Jeng Lee, Jung-Hua Lee, Gene-Hsiang Lee, Shie-Ming Peng, Shiuh-Tzung Liu
Under mild conditions, reactions of (CO)5MC[N(R)CH2]2 [M = W, Mo, Cr; R = Et, allyl, benzyl, 4-pentenyl] with (PhCN)2PdCl2, (PhCN)2PtCl2, [(CO)2RhCl]2, (Me2S)AuCl, [(CH3CN)4Cu]BF4, and AgBF4 provide the corresponding diaminocarbene complexes via carbene ligand transfer. The resulting Pd(II), Pt(II), Rh(I), and Au(I) carbene complexes are stable and were isolated. The Cu(I) and Ag(I) complexes readily undergo acid-induced MC cleavage to yield the imidazolidin-2-ylidinium salts. The carbene-transfer reactions were studied for two phosphine donors:  (CO)m(L)WC[N(R)CH2]2 {R = Et, benzyl; L = PPh3, m = 4; L = dppe, m = 3}. The X-ray crystal structures of (CO)5WC[N(CH2C6H5)CH2]2 (1c), cis-(CO)4(PPh3)WC[N(CH2C6H5)CH2]2 (5b), fac-(CO)3(dppe)WC[N(CH2C6H5)CH2]2 (6b), Cl2(CO)PtC[N(CH2C6H5)CH2]2 (9c), and cis-Cl2Pt{=C[N(CH2C6H5)CH2]2}2 (11b) are reported.