d-Penicillamine derived thiazolidine ligands were prepared in a two-step synthetic sequence and used in the enantioselective alkylation of a variety of aromatic aldehydes with diethylzinc at room temperature. Excellent ee, up to >99%, and nearly complete conversions were observed. Structurally analogous l-cysteine derived thiazolidine ligands were also synthesized and tested for comparative purposes
Synthesis of Chiral Pyridylphenols for the Enantioselective Addition of Diethylzinc to Aldehydes
作者:Pei-Shan Wu、Chinpiao Chen
DOI:10.1002/jccs.201100474
日期:2012.6
Chiral 8‐substituted 2‐(8,10,10‐trimethyl‐6‐aza‐tricyclo[7.1.1.02,7]undeca‐2(7),3,5‐trien‐5‐yl)‐phenols were prepared from a high enantiopurity (>97% ee) of (1R)‐(+)‐α‐pinene, and assessed in the enantioselectiveaddition of diethylzinc to substituted benzaldehydes, giving the (S)‐alcohols with enantiomeric excess ranging from 33% to 89%. Interestingly, in all cases, except for those of ortho‐chlorobenzaldehyde
An Amino Alcohol Ligand for Highly Enantioselective Addition of Organozinc Reagents to Aldehydes: Serendipity Rules
作者:William A. Nugent
DOI:10.1021/ol0259488
日期:2002.6.1
bis(2-bromoethyl) ether. Subsequent hydrogenation over 5% Rh on alumina in the presence of morpholine unexpectedly stops at the hexahydro derivative 4. Amino alcohol 4 promotes the enantioselectiveaddition of diethylzinc to aldehydes at room temperature in up to 99% enantiomeric excess.
New chiral ligands derived from (+) and (−)-α-pinene for the enantioselective addition of diethylzinc to aldehydes
作者:Gustavo Frensch、Ricardo Labes、Celso Luiz Wosch、Laieli dos Santos Munaretto、Kahlil Schwanka Salomé、Palimécio G. Guerrero、Francisco A. Marques
DOI:10.1016/j.tetlet.2015.12.042
日期:2016.1
In this study, we synthesized five new chiral ligands from (+) and (−)-α-pinene, which were successfully employed in the stereoselective addition of diethylzinc to aldehydes, leading to secondary chiral alcohols in up to 99% yield and 94% e.e.
在这项研究中,我们从(+)和(-)-α-pine烯合成了五个新的手性配体,这些配体成功地用于将二乙基锌立体选择性地加成到醛中,从而产生仲手性醇,收率高达99%和94% ee
Asymmetric diethylzinc addition and phenyl transfer to aldehydes using chiral cis-cyclopropane-based amino alcohols
作者:Jiangchun Zhong、Hongchao Guo、Mingan Wang、Mingming Yin、Min Wang
DOI:10.1016/j.tetasy.2007.03.006
日期:2007.4
A new series of aminoalcohols with a chiral cyclopropane backbone have been developed and used in the catalytic asymmetric diethylzinc addition and phenyl transfer to various types of aldehydes. These cyclopropane-based chiral aminoalcohols show high enantioselectivity in the addition of organozincs to aromatic and aliphatic aldehydes. For diethylzinc addition to aromatic and aliphatic aldehydes