Regio‐ and Diastereoselective Copper‐Catalyzed Carbomagnesiation for the Synthesis of Penta‐ and Hexa‐Substituted Cyclopropanes
作者:Yair Cohen、André U. Augustin、Laura Levy、Peter G. Jones、Daniel B. Werz、Ilan Marek
DOI:10.1002/anie.202102509
日期:2021.5.17
Despite the highly strained nature of cyclopropanes possessing three vicinal quaternary carbon stereocenters, the regio‐ and diastereoselective copper‐catalyzed carbomagnesiation reaction of cyclopropenes provides an easy and efficient access to these novel persubstituted cyclopropyl cores with a complete regio‐ and diastereoselectivity.
Selectivity in Rhodium(II)-Catalyzed Rearrangements of cycloprop-2-ene-1-carboxylates
作者:Paul Müller、Christian Gränicher
DOI:10.1002/hlca.19950780113
日期:1995.2.8
substituents of the cyclopropene ring. Product composition is markedly influenced by the number, nature, and position of the substituents, which determine the regio- and stereoselectivity of the cyclopropene-ring cleavage. A mechanism is proposed in which attack of the electrophilic RhII species is concerted with disrotatoryringopening of the incipient cyclopropyl cation and affords a metal-complexed
Borylated Cyclopropanes as Spring-Loaded Entities: Access to Vicinal Tertiary and Quaternary Carbon Stereocenters in Acyclic Systems
作者:André U. Augustin、Sergio Di Silvio、Ilan Marek
DOI:10.1021/jacs.2c07394
日期:2022.9.14
formation of acyclic frameworks bearing two consecutive stereocenters of either tertiary or quaternary nature starting from easily accessible cyclopropenes. This holistic approach involves a regio- and diastereoselective hydro- or carboborylation of substituted cyclopropenyl esters. Formation of boronate complexes of the latter via the addition of nucleophiles and subsequent stereospecific 1,2-migration
Synthesis and Functionalization of Tertiary Propargylic Boronic Esters by Alkynyllithium-Mediated 1,2-Metalate Rearrangement of Borylated Cyclopropanes
作者:Tereza Pavlíčková、Yannick Stöckl、Ilan Marek
DOI:10.1021/acs.orglett.2c03756
日期:2022.12.9
Implementing the use of alkynyllithium reagents in a stereospecific 1,2-metalate rearrangement-mediated ring opening of polysubstituted cyclopropyl boronicesters provides a variety of tertiary pinacol boranes bearing adjacent tertiary or quaternary carbon stereocenters with high levels of diastereomeric purity. The potential of this strategy was demonstrated through a selection of α- and γ-functionalization