Enantioselective NiH/Pmrox-Catalyzed 1,2-Reduction of α,β-Unsaturated Ketones
作者:Fenglin Chen、Yao Zhang、Lei Yu、Shaolin Zhu
DOI:10.1002/anie.201610990
日期:2017.2.13
presence of pinacolborane. This mild process represents a general method to access a wide variety of structurally diverse α‐chiral allylic alcohols in excellent yields and enantioselectivity, as well as very high levels of ambidoselectivity for 1,2‐ over 1,4‐reduction. Furthermore, for reactions on a 10 mmol scale, catalyst loadings as low as 0.5 mol % could be employed to deliver product without any
Catalytic Asymmetric Transfer Hydrogenation of <i>trans</i>-Chalcone Derivatives Using BINOL-derived Boro-phosphates
作者:Fei Na、Susana S. Lopez、Alice Beauseigneur、Lucas W. Hernandez、Zhuoxin Sun、Jon C. Antilla
DOI:10.1021/acs.orglett.0c02042
日期:2020.8.7
Chiral phosphoric-acid-catalyzed asymmetric reductions of trans-chalcones have been investigated in this work. A BINOL-derived boro-phosphate-catalyzed asymmetric transfer hydrogenation of the carbon–carbon double bond of trans-chalcone derivatives employing borane as a hydride source was realized. This methodology provides a convenient procedure to accesschiral dihydrochalone derivatives in high
An asymmetric hydrogenation of sterically hindered β,β-disubstituted enones has been well-established by using a ruthenium complex composed of an achiral diphosphane and a chiral diamine as catalyst, wherein the carbonyl group was selectively hydrogenated to give a wide range of chiral allylic alcohols with high levels of enantioselectivity and complete chemoselectivity.
Alcohol Dehydrogenases and N‐Heterocyclic Carbene Gold(I) Catalysts: Design of a Chemoenzymatic Cascade towards Optically Active β,β‐Disubstituted Allylic Alcohols
combination of gold(I) and enzyme catalysis is used in a two-step approach, including Meyer–Schuster rearrangement of a series of readily available propargylicalcohols followed by stereoselective bioreduction of the corresponding allylic ketone intermediates, to provide optically pure β,β-disubstituted allylic alcohols. This cascade involves a gold N-heterocycliccarbene and an enzyme, demonstrating the
Trisubstituted allylicethers undergo intermolecular oxymercurations with good to excellent diastereoselectivity compared to the corresponding allylic alcohols.