Optically Active 1,1′-Spirobiindane-7,7′-diol (SPINOL)-Based Phosphoric Acids as Highly Enantioselective Catalysts for Asymmetric Organocatalysis
作者:Chun-Hui Xing、Yuan-Xi Liao、Jaclynn Ng、Qiao-Sheng Hu
DOI:10.1021/jo200302x
日期:2011.5.20
of optically active 1,1′-spirobiindane-7,7′-diol (SPINOL)-based phosphoricacids are described. These SPINOL-based phosphoricacids were prepared from (R)-SPINOL in three steps and exhibited excellent enantioselectivities for the reactions of indoles with aldimines and β,γ-unsaturated-α-ketoesters. Our study provides a family of promising chiral phosphoricacids to the asymmetric organocatalysis toolbox
Chiral Spiro Phosphoramide-Catalyzed Sulfa-Michael Addition/Enantioselective Protonation of Exocyclic Enones
作者:Yi-Pan Li、Shou-Fei Zhu、Qi-Lin Zhou
DOI:10.1021/acs.orglett.9b03615
日期:2019.12.6
A highly efficient asymmetric Michael addition of thiols to exocyclic enones was achieved by using chiral spiro phosphoramide catalysts. The precisely chiral control in the protonation of the enol intermediate ensured high enantioselectivity. The reaction features high activity (yields up to 99%, turnover numbers up to 8400) and high enantioselectivity (up to 97% ee) with a broad substrate scope, and
Atroposelectiveelectrophilicsulfenylation of N-aryl aminoquinonederivativescatalyzed by a new chiral SPINOL-derived sulfide has been achieved. Axially chiral sulfur-containing diarylamine derivatives were obtained in moderate to excellent yields with moderate to excellent enantioselectivities. The intramolecular N−H⋅⋅⋅S hydrogen bond is a key parameter for the stability of the C−N axis. DFT calculations
A highlyenantioselective free carbene insertion into the N−H bond of amines has been achieved. Newly designed high-pKa Brønsted acid catalysts, chiral spiro phosphamides, were found to be key and promote the proton transfer of the ylide intermediates and control the enantioselectivity of the reaction. The reaction provides a new approach to amino acid derivatives.
已经实现了将高度对映选择性的游离卡宾插入到胺的 N-H 键中。发现新设计的高 p Ka Brønsted酸催化剂、手性螺磷酰胺是关键,可促进叶立德中间体的质子转移并控制反应的对映选择性。该反应为氨基酸衍生物的制备提供了一种新途径。