TY - JOUR
T1 - Amidophosphine-phosphinites
T2 - Synthesis and use in rhodium-based asymmetric hydrogenation of activated keto compounds. Crystal structure of bis[(μ-chloro)((S)-2-((diphenylphosphino)oxy)-2-phenyl-N-(diphenylphosphino)- N-methylacetamide)rhodium(I)]
AU - Roucoux, Alain
AU - Thieffry, Laurent
AU - Carpentier, J. F.
AU - Devocelle, Marc
AU - Méliet, Catherine
AU - Agbossou, Francine
AU - Mortreux, André
AU - Welch, Alan J.
PY - 1996/5/14
Y1 - 1996/5/14
N2 - Amidophosphine-phosphinite ligands (AMPP) derived from (S)-N-benzylmandelamide ((S)-R,R'-benzylmandelNOP (S)-1 (R = R' = phenyl) and (S)-7 (R = phenyl, R' = cyclopentyl)), (S)-N-methylmandelamide ((S)-R,R'-methylmandelNOP (S)-2 (R = R' = phenyl) and (S)-8 R = phenyl, R' = cyclopentyl)), (S)-N-methyllactamide ((S)-R,R'-methyllactaNOP (S)-3 (R = R' = phenyl) and (S)-9 (R = phenyl, R' = cyclopentyl)), and (S)-2-hydroxymethyl)-2-pyrrolidinone ((S)-R,R'-oxoProNOP (S)-4-6 and (S)-10 (R, R' = phenyl, cyclohexyl, cyclopentyl)) have been prepared in high yields (60-94%) and reacted with rhodium Precursors to prepare neutral "Rh{AMPP}" complexes 11-26 of general formula [Rh{AMPP}X]2, where X = Cl, I, OCOCH3, OCOCF3, and OCOC3F7. The crystal structure of [Rh{(S)-Ph,Ph-methylmandelNOP}Cl]2 (12) has been determined. The rhodium atom has a cis square-planar coordination, and the seven-membered chelate ring has a boat conformation with the nitrogen atom in the mean plane RhP2. Complexes 11-26 have been used as catalyst precursors for the asymmetric hydrogenation of dihydro-4,4-dimethyl-2,3-furandione (27) and N-benzylbenzoylformamide (29) giving the corresponding optically active hydroxy compounds 28 and 30 in high yields and low to high enantiomeric excesses (28-98.7% ee and 13-87% ee, respectively). Catalytic activities (turnover frequency at 50% conversion at room temperature up to 3300 h-1) as well as the enantioselectivities depended strongly on the nature of the substituents on phosphorus as well as on the nature of the non chiral ligands. Catalyst precursor [Rh{(S)-Cp,Cp-oxoProNOP}OCOCF3]2 afforded (R)-pantolactone in 98.7% ee.
AB - Amidophosphine-phosphinite ligands (AMPP) derived from (S)-N-benzylmandelamide ((S)-R,R'-benzylmandelNOP (S)-1 (R = R' = phenyl) and (S)-7 (R = phenyl, R' = cyclopentyl)), (S)-N-methylmandelamide ((S)-R,R'-methylmandelNOP (S)-2 (R = R' = phenyl) and (S)-8 R = phenyl, R' = cyclopentyl)), (S)-N-methyllactamide ((S)-R,R'-methyllactaNOP (S)-3 (R = R' = phenyl) and (S)-9 (R = phenyl, R' = cyclopentyl)), and (S)-2-hydroxymethyl)-2-pyrrolidinone ((S)-R,R'-oxoProNOP (S)-4-6 and (S)-10 (R, R' = phenyl, cyclohexyl, cyclopentyl)) have been prepared in high yields (60-94%) and reacted with rhodium Precursors to prepare neutral "Rh{AMPP}" complexes 11-26 of general formula [Rh{AMPP}X]2, where X = Cl, I, OCOCH3, OCOCF3, and OCOC3F7. The crystal structure of [Rh{(S)-Ph,Ph-methylmandelNOP}Cl]2 (12) has been determined. The rhodium atom has a cis square-planar coordination, and the seven-membered chelate ring has a boat conformation with the nitrogen atom in the mean plane RhP2. Complexes 11-26 have been used as catalyst precursors for the asymmetric hydrogenation of dihydro-4,4-dimethyl-2,3-furandione (27) and N-benzylbenzoylformamide (29) giving the corresponding optically active hydroxy compounds 28 and 30 in high yields and low to high enantiomeric excesses (28-98.7% ee and 13-87% ee, respectively). Catalytic activities (turnover frequency at 50% conversion at room temperature up to 3300 h-1) as well as the enantioselectivities depended strongly on the nature of the substituents on phosphorus as well as on the nature of the non chiral ligands. Catalyst precursor [Rh{(S)-Cp,Cp-oxoProNOP}OCOCF3]2 afforded (R)-pantolactone in 98.7% ee.
M3 - Article
SN - 1520-6041
VL - 15
SP - 2440
EP - 2449
JO - Organometallics
JF - Organometallics
IS - 10
ER -