Enantioselective Catalysis; 130: Optically Active Expanded Ligands Based on the trans-1,2-Substituted Cyclopentane Skeleton
作者:Henri Brunner
DOI:10.1055/s-1999-3597
日期:1999.10
New expanded bisphosphane ligands with a chiral trans-1,2-substituted cyclopentane skeleton were prepared. Polyaldehydes were accessible by coupling optically active bisphosphane precursors with branched aryl bromides. Optically active expanded ligands were obtained by condensation of the aldehydes with chiral amines and amino alcohols. The optically active ligands were tested in several model reactions of enantioselective catalysis, including allylic alkylation, hydrogenation (adopted to the use of water), and hydrosilylation.
Chirale Bisphosphane IX. Kationische Rhodium(I)-Komplexe mit (1S,2S)-Cyclopentan-1,2-diyl-bis(dialkylphosphan)-Liganden, [(1S,2S)-C5H8(PR2)2Rh(1,5-COD)]O3SCF3: Synthesen, Strukturen und katalytische Anwendungen
作者:Lutz Dahlenburg、Volker Kurth
DOI:10.1016/s0022-328x(99)00243-0
日期:1999.8
(2) by Grignard substitution. Combination of (1S,2S)-C5H8P(Cl)C8H15-cyclo}2 (4) with CH3MgBr or of (1S,2S)-C5H8P(H)C8H15-cyclo}2 (3) with n-C4H9Li and CH3I afforded (1S,2S)-C5H8P(CH3)C8H15-cyclo}2 (9) as diastereomeric mixtures containing the SP,SP', RP,RP', and RP,SP' stereoisomers 9a–c in different proportions. The optically active chelate ligands 5–9 reacted with [Rh(1,5-COD)2]O3SCF3 to give cationic
在烯丙醇或1,4-戊二烯中自由基引发的P-H(1 S,2 S)-C 5 H 8(PH 2)2(1)的加成产生了全烷基化的手性P 2配体(1 S,2 S)-C 5 H ^ 8 P(C 3 H ^ 6 OH)2 } 2(6)和(1小号,2小号)-C 5 H ^ 8(PC 5 ħ 10 -环)2(7)。(1 S,2 S)-C 5 H 8(PR 2)2类型的其他P烷基化双膦,其中PR 2 = P(C 4 H 9 - n)2(5)和P(C 6 H 11 -环)2(8)由(1 S,2 S)-C 5 H 8(PCl 2)2(2)由格利雅(Grignard)替代。(1组合小号,2小号)-C 5 H ^ 8 P(CL)C 8 H ^ 15 -环} 2(4)用CH 3 MgBr或(1小号,2小号)-C 5 H ^ 8 P (H)C 8 H ^ 15 -环} 2(3)与ñ -C 4 ħ 9 Li和CH 3我得到(1小号,2小号)-C
P-Alkylated (1S,2S)-Cyclopentane-1,2-diylbisphosphanes with Four Stereogenic Centers and Some Group 10 Metal(II) Complexes Containing the (1S,2S)-C5H8[P(CH3)C8H15-cyclo]2 Ligand