Solvent-Dependent Enantiodivergence in the Chlorocyclization of Unsaturated Carbamates
作者:Atefeh Garzan、Arvind Jaganathan、Nastaran Salehi Marzijarani、Roozbeh Yousefi、Daniel C. Whitehead、James E. Jackson、Babak Borhan
DOI:10.1002/chem.201300189
日期:2013.7.1
A remarkable solvent‐controlled enantiodivergence is seen in the hydroquinidine 1,4‐phthalazinediyl diether ((DHQD)2PHAL)‐catalyzed chlorocyclization of unsaturatedcarbamates. Eyring plot analyses of this previously unreported reaction are used to probe and compare the R‐ and S‐selective pathways. In the CHCl3/hexanes solvent system, the pro‐R process shows a surprising increase in selectivity with
CO<sub>2</sub>-Assisted asymmetric hydrogenation of prochiral allylamines
作者:Tamara M. de Winter、Jaddie Ho、Christopher J. Alridge、Philip G. Jessop
DOI:10.1039/d2ra00263a
日期:——
A new methodology for the asymmetric hydrogenation of allylamines takes advantage of a reversible reaction between amines and carbon dioxide (CO2) to suppress unwanted side reactions. The effects of various parameters (pressure, time, solvent, and base additives) on the enantioselectivity and conversion of the reaction were studied. The homogeneously-catalyzed asymmetric hydrogenation of 2-arylprop-2-en-1-amine
Catalytic asymmetric CO<sub>2</sub> utilization reaction for the enantioselective synthesis of chiral 2-oxazolidinones
作者:Ryuichi Nishiyori、Taiki Mori、Seiji Shirakawa
DOI:10.1039/d3ob00555k
日期:——
asymmetric bromocyclizations of in situgenerated carbamic acids from CO2 and allylamines were achieved via the use of a BINOL-derived chiral bifunctional selenide catalyst bearing a hydroxy group. Chiral 2-oxazolidinone products as important pharmaceutical building blocks were obtained with good enantioselectivities by the present catalytic asymmetric CO2 utilization reactions.
通过使用带有羟基的 BINOL 衍生的手性双功能硒化物催化剂,实现了由 CO 2和烯丙胺原位生成的氨基甲酸的催化不对称溴化环化。通过本催化不对称CO 2利用反应获得了具有良好对映选择性的手性2-恶唑烷酮产物作为重要的药物结构单元。