Carbene-catalyzed enal γ-carbon addition to α-ketophosphonates for enantioselective access to bioactive 2-pyranylphosphonates
作者:Jun Sun、Fangcheng He、Zhongyao Wang、Dingwu Pan、Pengcheng Zheng、Chengli Mou、Zhichao Jin、Yonggui Robin Chi
DOI:10.1039/c8cc03017k
日期:——
A carbene-catalyzed enantioselective [4+2] cycloaddition reaction between α,β-unsaturated aldehydes and α-ketophosphonates is developed. The reaction affords chiral 2-pyranylphosphonates with excellent enantioselectivities. The optically enriched phosphonate products bear multiple functional groups, including unsaturated lactone and phosphonate moieties that often lead to unique bio-activities. Preliminary
Carbene-Catalyzed Formal [3+3] Cycloaddition Reaction for Access to Substituted 2-Phenylbenzothiazoles
作者:Zhibin Ni、Chengli Mou、Xun Zhu、Puying Qi、Song Yang、Yonggui Robin Chi、Zhichao Jin
DOI:10.1002/ejoc.201901773
日期:2020.1.31
carbene‐catalyzed oxidative cycloadditionreaction is developed for efficient access to multi‐functionalized 2‐phenylbenzothiazoles. A broad scope of heavily substituted arenes bearing 2‐benzothiazole groups have been prepared in good to excellent yields. The remote C(sp2)–H bond in the substituted arene products can be regioselectively activated by Pd catalysts with the direction of the 2‐benzothiazole groups
N-Heterocyclic Carbene-Catalyzed α,β-Unsaturated Aldehydes Umpolung in Fullerene Chemistry: Construction of [60]Fullerene-Fused Cyclopentan-1-ones and Cyclohex-2-en-1-ones
first umpolung strategy for the cycloacylation of fullerene using a N-heterocyclic carbene organocatalyst is reported. The coupling of [60]fullerene with different structural α,β-unsaturated aldehydes efficiently furnishes interesting [60]fullerene-fused cyclopentan-1-ones or cyclohex-2-en-1-ones in good to excellent yields. This newreaction displays a wide substrate scope and excellent functional-group
Carbene-Catalyzed Formal [5 + 5] Reaction for Coumarin Construction and Total Synthesis of Defucogilvocarcins
作者:Xuan Huang、Tingshun Zhu、Zhijian Huang、Yuexia Zhang、Zhichao Jin、Giuseppe Zanoni、Yonggui Robin Chi
DOI:10.1021/acs.orglett.7b03102
日期:2017.11.17
An N-heterocyclic carbene-catalyzed formal [5 + 5] reaction between enals and furanones that generates multisubstituted coumarins in a single step is reported. Five atoms in each of the substrates are involved in this catalytic process to form a benzene and a lactone ring. The power of the method is further demonstrated in metal-free total syntheses of several natural products (defucogilvocarcins M
N‐Heterocyclic Carbene Catalyzed Synthesis of Dihydroxybenzophenones from β‐Methylenals and Aurones
作者:Kun‐Quan Chen、Zhi Luo、Zhong‐Hua Gao、Song Ye
DOI:10.1002/chem.201806225
日期:——
N‐heterocyclic carbene catalyzed synthesis of 2,2′‐dihydroxybenzophenones from β‐methylenals and aurones was developed. The cleavage of the C−O bond by a retro‐Michael addition is the key step from the spirocyclic intermediate to final product.