An efficient RhII -catalyzed synthesis of functionalized α-vinyl aldehydes with high E/Z stereoselectivity was developed. The reaction mediates the cyclopropanation of enaminones with vinyl carbenoids that are generated from cyclopropenes in situ to give the aminocyclopropane intermediates. Selective C-C bond cleavage of the cyclopropane intermediates leads to formation of α-vinyl aldehyde derivatives
We report realization of the first enantioselective Cope-type hydroamination of oximes for asymmetric nitrone synthesis. The ligand promoted asymmetriccyclopropene “hydronitronylation” process employs a Cu-based catalytic system and readily available starting materials, operates under mild conditions and displays broad scope and exceptionally high enantio- and diastereocontrol. Preliminary mechanistic
Tandem Hydroalumination/Cu-Catalyzed Asymmetric Vinyl Metalation as a New Access to Enantioenriched Vinylcyclopropane Derivatives
作者:Daniel S. Müller、Veronika Werner、Sema Akyol、Hans-Günther Schmalz、Ilan Marek
DOI:10.1021/acs.orglett.7b01661
日期:2017.8.4
Herein, we report the first enantio- and diastereoselective addition of stereodefined vinyl organometallicreagents to cyclopropenes. The operationally simple tandem hydroalumination and copper-catalyzed vinylmetalation allows for the unique access of a diverse set of enantioenriched vinylcyclopropane derivatives.
Highly Diastereoselective Synthesis of Polysubstituted Cyclopropanecarbonitriles via Palladium-Catalyzed Cyanoesterification of Cyclopropenes
作者:Can Li、Rongrong Yu、Song-Zhou Cai、Xianjie Fang
DOI:10.1021/acs.orglett.3c01875
日期:2023.7.14
We herein develop a highlydiastereoselectivesynthesis of cyano-substituted cyclopropanes via palladium-catalyzed direct cyanoesterification of cyclopropenes, which features mild reaction conditions, good functional group compatibility, and simple operation. This transformation represents a stepwise, highly atom economic, and scalable protocol for obtaining synthetically useful cyclopropanecarbonitriles
An asymmetric hydrophosphination of 3,3-disubstituted cyclopropenes catalyzed by Cu(I)-(R,R)-QUINOXP* is developed, affording a series of phosphine derivatives in high to excellent diastereo- and enantioselectivities.
开发了 Cu(I)-( R , R )-QUINOXP*催化的 3,3-二取代环丙烯的不对称氢膦化反应,提供了一系列具有高至优异的非对映选择性和对映选择性的膦衍生物。