Enantiopure P‐aryl‐2,5‐diphenylphospholanes and its corresponding P‐aryl‐phospholanium salt appear as very efficientligands for rhodium‐catalyzed asymmetrichydrogenation reaction with similar activities and enantioselectivities. The hydrogenation product was obtained in good enantiomeric excesses (up to 93 % ee) in only few minutes under an atmospheric pressure of dihydrogen. The excellent activity
(S,S)-1,2,5-Triphenylphospholanium tetrafluoroborate salt 2 was conveniently used as chiral ligand precursor in rhodium-catalyzed asymmetrichydrogenation of methyl (Z)-2-acetamidocinnamate. 31P NMR showed the existence of a solvent-dependent equilibrium between the salt and the free phosphine.
(S,S)-1,2,5-三苯基磷鎓四氟硼酸盐2方便地用作铑催化的(Z)-2-乙酰氨基二十二酸甲基酯的不对称氢化中的手性配体前体。31 P NMR表明盐和游离膦之间存在溶剂依赖性平衡。
Enantioselective synthesis of allenic esters via an ylide route
作者:Chuan-Ying Li、Xiu-Li Sun、Qing Jing、Yong Tang
DOI:10.1039/b603659g
日期:——
Pseudo-C2-symmetric chiral phosphorus ylides have been designed and synthesized for the enantioselective preparation of allenicesters, and up to 92% ee has been achieved.
Pseudo-C2-symmetric chiral phosphorus ylide is designed and synthesized for the enantioselective preparation of allenic esters, amides, ketone, and nitrile. Up to 92% ee is achieved.
设计并合成了伪C 2对称的手性磷叶立德,用于对映体制备烯丙酸酯,酰胺,酮和腈。达到了92%ee。
Synthesis and first applications of a new family of chiral monophosphine ligand: 2,5-diphenylphosphospholanes
The cyclic phosphinic acid 1-hydroxy-1-r-oxo-2c,5-t-diphenylphospholane was synthesized and resolved into enantiomers through fractional crystallization of the quinine salts. The P-phenyl, P-methyl and P-benzyl tertiary phosphine oxides were obtained from the secondary phosphine oxide, reduction of the oxides afforded the corresponding tertiary P-phenyl and P-benzyl phosphines. Hydrogenation of prochiral