Development of Non-<i>C</i>2-symmetric ProPhenol Ligands. The Asymmetric Vinylation of <i>N</i>-Boc Imines
作者:Barry M. Trost、Chao-I (Joey) Hung、Dennis C. Koester、Yan Miller
DOI:10.1021/acs.orglett.5b01755
日期:2015.8.7
The development and application of a newgeneration of non-C2-symmetric ProPhenol ligands is reported herein. Rational design of the ProPhenol ligand paved the way to the first catalytic and asymmetric vinylation of N-Boc imines via hydrozirconation giving rise to valuable allylic amines in excellent yields and enantioselectivities. The utility of this method was demonstrated by developing the shortest
Direct Catalytic Asymmetric Mannich Reaction with Dithiomalonates as Excellent Mannich Donors: Organocatalytic Synthesis of (<i>R</i>)-Sitagliptin
作者:Han Yong Bae、Mun Jong Kim、Jae Hun Sim、Choong Eui Song
DOI:10.1002/anie.201605167
日期:2016.8.26
enantioselectivity (up to 99 % ee). Furthermore, by the use of a DTM, even some highly challenging primary alkyl α‐amidosulfones were smoothly converted into the desired adducts with excellent enantioselectivity (up to 97 % ee), whereas the use of a malonate or monothiomalonate resulted in no reaction under identical conditions. The synthetic utility of the chiral Mannich adducts obtained from primary alkyl substrates
Borane-Catalyzed Direct Asymmetric Vinylogous Mannich Reactions of Acyclic α,β-Unsaturated Ketones
作者:Jun-Jie Tian、Ning Liu、Qi-Fei Liu、Wei Sun、Xiao-Chen Wang
DOI:10.1021/jacs.1c00006
日期:2021.3.3
Herein, we report that, by using chiral bicyclic bisborane catalysts, we have achieved the first highly regio-, diastereo-, and enantioselective direct asymmetric vinylogous Mannich reactions of acyclic α,β-unsaturatedketones. The strong Lewis acidity and steric bulk of the bisborane catalysts were essential for the observed high yields and selectivities.
A direct catalytic asymmetric vinylogous Mannich-typereaction has been disclosed in good yield, excellent regio-, diastereo- and enantioselectivity. The key to control the regioselectivity is the combination of a bulky N-acylpyrazole and a bulky bisphosphine ligand. The catalytic system was extended to a bisvinylogous Mannich-typereaction by changing the ligand. The synthetic utility of the vinylogous
Direct Catalytic Asymmetric Vinylogous Mannich-Type and Michael Reactions of an α,β-Unsaturated γ-Butyrolactam under Dinuclear Nickel Catalysis
作者:Nicholas E. Shepherd、Hirooki Tanabe、Yingjie Xu、Shigeki Matsunaga、Masakatsu Shibasaki
DOI:10.1021/ja1002636
日期:2010.3.24
Directcatalyticasymmetricvinylogous reactions of an alpha,beta-unsaturated gamma-butyrolactam as a donor are described. A homodinuclear Ni(2)-Schiff base complex promoted a vinylogous Mannich-type reaction of N-Boc imines as well as a vinylogousMichael reaction to nitroalkenes selectively at the gamma-position under simple proton-transfer conditions. Vinylogous Mannich adducts were obtained in
描述了作为供体的 α,β-不饱和 γ-丁内酰胺的直接催化不对称乙烯基反应。在简单的质子转移条件下,同双核 Ni(2)-Schiff 碱配合物促进了 N-Boc 亚胺的乙烯基曼尼希型反应,以及选择性地在 γ 位与硝基烯烃的乙烯基迈克尔反应。Vinylogous Mannich 加合物在 5:1-->30:1 dr 和 99% ee 中获得,而vinylogous Michael 加合物在 16:1-->30:1 dr 和 93-99% ee 中获得。