Bifunctional Phosphonium Salt Directed Enantioselective Formal [4 + 1] Annulation of Hydroxyl-Substituted <i>para</i>-Quinone Methides with α-Halogenated Ketones
作者:Jian-Ping Tan、Peiyuan Yu、Jia-Hong Wu、Yuan Chen、Jianke Pan、Chunhui Jiang、Xiaoyu Ren、Hong-Su Zhang、Tianli Wang
DOI:10.1021/acs.orglett.9b02560
日期:2019.9.20
A highly diastereo- and enantioselective [4 + 1] cycloaddition of para-quinone methides to α-halogenated ketones was realized by bifunctional phosphonium salt catalysis, furnishing functionalized 2,3-dihydrobenzofurans in high yields and excellent stereoselectivities (>20:1 dr and up to >99.9% ee). Mechanistic observations suggested that the reaction underwent a cascade intermolecular substitution/intramolecular
Highly Enantioselective Synthesis of Fused Tri‐ and Tetrasubstituted Aziridines: aza‐Darzens Reaction of Cyclic Imines with α‐Halogenated Ketones Catalyzed by Bifunctional Phosphonium Salt
作者:Jianke Pan、Jia‐Hong Wu、Hongkui Zhang、Xiaoyu Ren、Jian‐Ping Tan、Lixiang Zhu、Hong‐Su Zhang、Chunhui Jiang、Tianli Wang
DOI:10.1002/anie.201900613
日期:2019.5.27
The first enantioselective aza‐Darzens reaction of cyclic imines with α‐halogenated ketones was realized under mild reaction conditions by using amino‐acid‐derived bifunctional phosphonium salts as phase‐transfer promoters. A variety of structurally dense tri‐ and tetrasubstituted aziridine derivatives, containing benzofused heterocycles as well as spiro‐structures, were readily synthesized in high yields
Enantioselective γ-Addition-Driven Cascade of β,γ-Unsaturated Ketones by Ion-Pair Catalysis: Access to Chiral 1,3-Dioxolochroman Scaffolds
作者:Xuemei Wang、Liang Zhou、Hongkui Zhang、Xiaoyu Ren、Guowei Gao、Tianli Wang
DOI:10.1021/acs.orglett.1c03567
日期:2022.1.14
A highlyenantioselective γ-addition-driven cascade of β,γ-unsaturated carbonyl compounds by bifunctional ion-pair catalysis has been developed. With this protocol, a range of functionalized chiral 1,3-dioxolochroman derivatives were prepared in high yields with superior stereoselectivities (>99% ee and >20:1 dr). The utility of this method was demonstrated by one-pot synthesis, scaled-up preparation
Highly Enantioselective Synthesis of Phosphorus‐Containing ϵ‐Benzosultams by Bifunctional Phosphonium Salt‐Promoted Hydrophosphonylation
作者:Song Zhang、Zhenghuai Feng、Chunhui Jiang、Xiaojun Yu、Jianke Pan、Juan Du、Zhiyu Jiang、Yuan Chen、Tianli Wang
DOI:10.1002/chem.202101038
日期:2021.8.5
with diverse biological activities. A series of chiral ϵ-benzosultams bearing phosphorus functionalities was synthesized by catalytic asymmetric hydrophosphonylation in the presence of a bifunctional phosphonium salt catalyst. The desired hydrophosphonylation products were obtained in good yields with high enantioselectivities, and scale-up reactions and further derivations were successfully accomplished
Highly Practical and Enantioselective Cu-Catalyzed Conjugate Addition of Alkylzinc Reagents to Cyclic Enones at Ambient Temperature
作者:Isaac J. Krauss、James L. Leighton
DOI:10.1021/ol034983r
日期:2003.9.1
[GRAPHICS]A new ligand for Cu-catalyzed enantioselective additions of dialkylzincs to cyclic enones has been developed. In addition to providing good to excellent enantioselectivities with a range of cyclic enones and dialkylzincs, the ligand has several notworthy features: it can be readily prepared in just two steps, is an air-stable crystalline solid, and provides optimal performance at ambient temperature.