Enantioselective Synthesis of Cyclopropanone Equivalents and Application to the Formation of Chiral β‐Lactams
作者:Christopher M. Poteat、Yujin Jang、Myunggi Jung、J. Drake Johnson、Rachel G. Williams、Vincent N. G. Lindsay
DOI:10.1002/anie.202006786
日期:2020.10.12
derivatives have long been considered unsustainable synthetic intermediates because of their extreme strain and kinetic instability. Reported here is the enantioselective synthesis of 1‐sulfonylcyclopropanols, as stable yet powerful equivalents of the corresponding cyclopropanone derivatives, by α‐hydroxylation of sulfonylcyclopropanes using a bis(silyl) peroxide as the electrophilic oxygen source. This
Rhodium/Silver Synergistic Catalysis in Highly Enantioselective Cycloisomerization/Cross Coupling of Keto-Vinylidenecyclopropanes with Terminal Alkynes
作者:Song Yang、Kang-Hua Rui、Xiang-Ying Tang、Qin Xu、Min Shi
DOI:10.1021/jacs.7b02027
日期:2017.4.26
catalysis, Rh(I) and Ag(I) catalysts selectively activate keto-VDCP substrates and terminal alkynes to generate the π-allyl Rh(III) complex of oxa-rhodacyclic intermediate and Ag alkynyl intermediate, respectively. The rapid transmetalation of alkynyl groups from Ag to Rh is proposed to play a key role in realizing the regioselectivecleavage of the distal bond of the three-membered ring in this transformation
已经建立了铑/银协同催化,使酮-亚乙烯基环丙烷 (VDCP) 与末端炔烃的环异构化/交叉偶联能够区域选择性和对映选择性地形成多样化的四氢吡啶-3-醇系链 1,4-烯炔,收率高且产率高ee 值。在这种协同催化中,Rh(I) 和 Ag(I) 催化剂选择性地激活酮-VDCP 底物和末端炔烃,分别生成氧杂-铑环中间体和 Ag 炔基中间体的 π-烯丙基 Rh(III) 配合物。炔基从 Ag 到 Rh 的快速金属转移被认为在实现该转变中三元环远端键的区域选择性裂解中发挥关键作用。
Grignard Reagent/CuI/LiCl-Mediated Stereoselective Cascade Addition/Cyclization of Diynes: A Novel Pathway for the Construction of 1-Methyleneindene Derivatives
作者:De-Yao Li、Yin Wei、Min Shi
DOI:10.1002/chem.201302191
日期:2013.11.11
Diynes containing a cyclopropane group smoothly undergo a novel intramolecular and stereoselective cascade addition/cyclization reaction to produce the corresponding 1‐methyleneindene derivatives in moderate to good yields. This interesting transformation is mediated by Grignard reagent/CuI with LiCl as an additive under mild conditions. The obtained product can easily be further functionalized through
Regio- and stereoselective hydrocyanation under nickel catalysis is described.
描述了在镍催化下的区域和立体选择性氢氰化。
Rhodium(III)-Catalyzed Controllable C−H Bond Functionalization of Benzamides and Vinylidenecyclopropanes: A Directing Group Determined Reaction Pathway
作者:Cheng Ji、Qin Xu、Min Shi
DOI:10.1002/adsc.201601308
日期:2017.3.20
A controllable rhodium(III)‐catalyzed C−H bond activation of benzamides and vinylidenecyclopropanes (VDCPs) by changing the directing group from C(O)NH–OPiv to C(O)NH–OBoc has been disclosed, affording two different major products in good yields under mild condition, respectively. The substrate scope has been investigated and a plausible reaction mechanism has been also proposed on the basis of previous