Et-duphos-nickel-catalyzed asymmetric arylation of benzaldehyde derivatives bearing an ortho-Me2PhSi group with potassium aryltriolborates
摘要:
The Ni-catalyzed asymmetric arylation of benzaldehydes bearing an ortho-masked H group with potassium aryltriolborates has been developed. The keys to success were (i) steric tuning of benzaldehyde derivatives with an ortho-Me2PhSi group, and (ii) the use of potassium aryltriolborates as aryl sources. (C) 2009 Elsevier Ltd. All rights reserved.
AlCl<sub>3</sub>and BDMAEE: A Pair of Potent Reactive Regulators of Aryl Grignard Reagents and Highly Catalytic Asymmetric Arylation of Aldehydes
作者:Xin-Yuan Fan、Yong-Xin Yang、Fang-Fang Zhuo、Sheng-Li Yu、Xiao Li、Qi-Peng Guo、Zhi-Xue Du、Chao-Shan Da
DOI:10.1002/chem.201000974
日期:2010.7.19
Cheap, energy‐saving, and applicable: With the aid of AlCl3 and BDMAEE [2,2′‐oxybis(N,N‐dimethylethanamine)], a highly asymmetriccatalytic addition of various aryl Grignard reagents to aldehydes was achieved under mild conditions with easily prepared (S)‐H8‐BINOL and inexpensive commercially available Ti(OiPr)4 (see scheme), and the reaction could be easily scaled up with no loss of yield and enantioselectivity
廉价,节能且适用:借助AlCl 3和BDMAEE [2,2'-氧双(N,N-二甲基乙胺)],在温和条件下,将各种芳基格氏试剂高度不对称催化加成到醛中用易于制备的(S)-H 8 -BINOL和便宜的市售Ti(O i Pr)4(参见方案),该反应可以轻松扩大规模,而不会损失收率和对映选择性。
Aryl Bromides as Inexpensive Starting Materials in the Catalytic Enantioselective Arylation of Aryl Aldehydes: The Additive TMEDA Enhances the Enantioselectivity
作者:Yong-Xin Yang、Yue Liu、Lei Zhang、Yan-E Jia、Pei Wang、Fang-Fang Zhuo、Xian-Tao An、Chao-Shan Da
DOI:10.1021/jo502070r
日期:2014.11.7
We used aryl bromides as inexpensive starting materials to enantioselectively arylate aldehydes in one pot. Aryl bromides readily transfer aryls to aryllithiums with n-butyllithium, successively to triarylaluminums with aluminum chloride, and then to aryltitaniums with titanium isopropoxide. Finally aryltitaniums arylate aldehydes catalyzed by (S)-H-8-BINOLTi(Oi-Pr)(2) in excellent yields and enantioselectivities. The additive TMEDA evidently suppresses the racemic background reaction promoted by LiCl generated from salt metathesis. This procedure represents a cost-effective and operationally convenient method for enantioenriched diarylmethanols.
Highly enantioselective addition of arylzinc reagents to aldehydes promoted by chiral aziridine alcohols
作者:Zuzanna Wujkowska、Szymon Jarzyński、Adam M. Pieczonka、Stanisław Leśniak、Michał Rachwalski
DOI:10.1016/j.tetasy.2016.10.005
日期:2016.12
Enantiomerically pure, chiral secondary and tertiary aziridine alcohols have proven to be highly efficient catalysts for enantioselective asymmetric additions of arylzinc species to aldehydes leading to products in high chemical yields (up to 90%) and with ee's up to 90%. The influence of the stereogenic centers located at the aziridine subunit on the stereochemical course of the reaction is discussed. (C) 2016 Elsevier Ltd. All rights reserved.
Et-duphos-nickel-catalyzed asymmetric arylation of benzaldehyde derivatives bearing an ortho-Me2PhSi group with potassium aryltriolborates
作者:Fumie Sakurai、Kazuhiro Kondo、Toyohiko Aoyama
DOI:10.1016/j.tetlet.2009.08.019
日期:2009.11
The Ni-catalyzed asymmetric arylation of benzaldehydes bearing an ortho-masked H group with potassium aryltriolborates has been developed. The keys to success were (i) steric tuning of benzaldehyde derivatives with an ortho-Me2PhSi group, and (ii) the use of potassium aryltriolborates as aryl sources. (C) 2009 Elsevier Ltd. All rights reserved.