conditions. In cooperation with a chiral‐phosphonium‐based phase‐transfer catalyst, the asymmetric direct oxidative allylic alkylations of 3‐substituted oxindoles are furnished under O2 atmosphere. The γ‐ or even remote ϵ‐regioselective alkylation products, with substantial substituents, are delivered with excellent enantioselectivity, and can be further used to accessdiversechiral spirocyclic architectures
Enantioselective Michael addition of 3-aryloxindoles to a vinyl bisphosphonate ester catalyzed by a cinchona alkaloid derived thiourea catalyst
作者:Mei-Xin Zhao、Tong-Lei Dai、Ran Liu、Deng-Ke Wei、Hao Zhou、Fei-Hu Ji、Min Shi
DOI:10.1039/c2ob25966d
日期:——
A highly enantioselective Michael addition of 3-aryloxindole to vinyl bisphosphonate ester catalyzed by a cinchonidine derived thiourea catalyst has been investigated. The corresponding adducts, containing a chiral quaternary carbon center and geminal bisphosphonate ester fragment at the 3-position of the oxindole, were obtained in moderate to good yields (65–92%) and moderate to good enantioselectivities
Stereodivergent Construction of Csp
<sup>3</sup>
−Csp
<sup>3</sup>
Bonds Bearing Vicinal Stereocenters by Synergistic Palladium and Phase‐Transfer Catalysis
作者:Jingqiang Han、Rixin Liu、Zitong Lin、Weiwei Zi
DOI:10.1002/anie.202215714
日期:2023.1.9
A stereodivergent Csp3−Csp3 coupling of 1,3-dienes with oxindoles was achieved by synergizing a palladium and a chiral phase-transfer catalyst in a biphasic system. Both the syn and anti products, which have vicinal quaternary and tertiary stereocenters, could be selectively achieved in good yields with high enantio- and diastereoselectivities. This is the first stereodivergent synthesis via metal/phase-transfer
Phosphine-Catalyzed Allylic Alkylation of (Hetero)Aryl Alkynes with Pronucleophiles: Concise Total Synthesis of (±)-Esermethole
作者:Ningtao He、Jilong Zhang、Xiaohe Miao、Dehai Li、De Wang
DOI:10.1021/acs.orglett.3c02275
日期:2023.8.25
Allylic alkylations are valuable in the construction of versatile carbon–carbon bonds, which are mostly catalyzed by noble transition metals with additional waste byproductgeneration. Here, we present the first organophosphine-catalyzed allylic alkylation of (hetero)aryl alkynes with various carbo-nucleophiles. The methodology is highly atom economical and compatible with a wide substrate scope (more