Design of Ru(II)-NHC-Diamine Precatalysts Directed by Ligand Cooperation: Applications and Mechanistic Investigations for Asymmetric Hydrogenation
作者:Wei Li、Tobias Wagener、Lars Hellmann、Constantin G. Daniliuc、Christian Mück-Lichtenfeld、Johannes Neugebauer、Frank Glorius
DOI:10.1021/jacs.0c00985
日期:2020.4.15
A modular synthesis of Ru(II)-NHC-diamine complexes from readily available chiral N-heterocyclic carbenes (NHCs) and chiraldiamines is disclosed for the first time. The well-defined Ru(II)-NHC-diamine complexes show unique structure and coordination chemistry including an unusual tridentate coordination effect of 1,2-diphenylethylenediamine. The isolated air- and moisture-stable Ru(II)-NHC-diamine
We herein report a general, practical, and highly efficient method for asymmetricsynthesis of a wide range of chiral vicinal diamines via reductive coupling of imines templated by chiral diboron. The protocol features high enantioselectivity and stereospecificity, mild reaction conditions, simple operating procedures, use of readily available starting materials, and a broad substrate scope. The method
for the preparation of enantiomericallyenriched C 2 -symmetrical vicinal diamines via the addition of organometallic reagents to a chiral bisimine, which gives access to a variety of optically pure aromatic and aliphatic C 2 -symmetrical vicinal diamines in high yields. The 'Cram-Davis' open transition state model is proposed to rationalize the observed stereoselectivities for the addition of organolithium
通过将有机金属试剂添加到手性双亚胺中,开发了一种有效且直接的制备对映体富集的 C 2 对称邻二胺的方法,该方法可以获得各种光学纯的芳香族和脂肪族 C 2 对称邻二胺高产量。提出了“Cram-Davis”开放过渡态模型,以合理化观察到的将有机锂试剂添加到双亚胺中的立体选择性。
A dual-catalysis approach to the kinetic resolution of 1,2-diaryl-1,2-diaminoethanes
作者:Chang Min、Nisha Mittal、Chandra Kanta De、Daniel Seidel
DOI:10.1039/c2cc36361e
日期:——
The kinetic resolution of racemic C2-symmetric 1,2-diaryl-1,2-diaminoethanes was accomplished for the first time through application of a dual-catalysis approach.
CHIRAL IRIDIUM AQUA COMPLEX AND METHOD FOR PRODUCING OPTICALLY ACTIVE HYDROXY COMPOUND USING THE SAME
申请人:Carreira Erick M.
公开号:US20110137049A1
公开(公告)日:2011-06-09
The invention provides a chiral iridium aqua complex which has good preservation stability, can be easily produced, and enables asymmetric transfer hydrogenation in a higher yield and with higher stereoselectivity. The chiral iridium aqua complex has the formula (1A):
wherein
R
a
, R
b
, R
c
, R
d
and R
e
are the same or different and each is a hydrogen atom, a methyl group, an ethyl group or a phenyl group,
R
1
and R
2
are the same or different and each is an aryl group optionally having substituent(s), or
R
1
and R
2
in combination show a C
3-4
straight chain alkylene group optionally having substituent(s) to form a ring,
R
3
is an alkylsulfonyl group optionally having substituent(s) or an arylsulfonyl group optionally having substituent(s),
R
4
is a hydrogen atom, an alkylsulfonyl group optionally having substituent(s) or an arylsulfonyl group optionally having substituent(s),
X is a monovalent or divalent anion, and
n is 2 when X is a monovalent anion, or n is 1 when X is a divalent anion,
and a production method of an optically active hydroxy compound using the complex.