Synthesis and characterization of ruthenium complexes of 1,8-bis(diphenylphosphinomethyl)naphthalene (BDNA) and their catalytic hydrogenation reactions to α, β-unsaturated aldehydes

• Published in: Journal of organometallic chemistry Vol. 571; no. 2; pp. 223 - 229
• Main Authors: Li, Rui-Xiang, Wong, Ning-Bew, Li, Xian-Jun, Mak, Thomas C.W, Yang, Qing-Chuan, Tin, Kam-Chung
• Format: Journal Article
• Language: English
• Published: LAUSANNE Elsevier B.V 10.12.1998; Elsevier
• Subjects: 1,8-Bis(diphenylphosphinomethyl)naphthalene; Chemistry; Chemistry, Inorganic & Nuclear; Chemistry, Organic; Cinnamaldehyde; Citral; Hydrogenation; Physical Sciences; Ruthenium complex; Science & Technology; Cinnamaldehyde; Hydrogenation; Citral; 1,8-Bis(diphenylphosphinomethyl)naphthalene; Ruthenium complex; citral; ACTIVATION; PHOSPHINE; 1,8-bis(diphenylphosphinomethyl)naphthalene hydrogenation; REDUCTION; LIGANDS; SYSTEMS; ALPHA; ruthenium complex; cinnamaldehyde; ASYMMETRIC HYDROGENATION; WATER
• ISSN: 0022-328X; 1872-8561
• DOI: 10.1016/S0022-328X(98)00889-4

A new ligand BDNA [1,8-bis(diphenylphosphinomethyl)naphthalene] and three ruthenium complexes containing the new ligand, Ru 2Cl 4(BDNA) 2 1, RuHCl(CO)(PPh 3)(BDNA) 2, and RuH 2(CO)(PPh 3)(BDNA) 3, have been synthesized. Their compositions and structures were characterized by 31P{ 1H}-NMR, 1H-NMR, and elemental analysis. Molecular structure of 3 was also confirmed by single-crystal X-ray diffraction. The crystal belonged to the triclinic crystal system, P1̄ space group, a=10.7450(7), b=12.7100(7), c=18.1390(13) Å, α=89.558(6), β=83.117(2), γ=80.859(5)°, V=2428.0(3) Å 3, and Z=2. The hydrogenation results of citral and cinnamaldehyde revealed that complex 2 had good catalytic activity and complex 3 had the high selectivity for the hydrogenation of CO bond in α, β-unsaturated aldehydes to form the corresponding allylic alcohols. In the presence of complex 3, very high selectivities of 99.5 and 95.1% were obtained for the hydrogenation of the carbonyl group in citral and cinnamaldehyde, respectively.