Diastereo- and enantioselective copper catalyzed hydroallylation of disubstituted cyclopropenes

Abstract

A highly diastereo- and enantioselective protocol for the hydroallylation of 1,1- and 1,2-disubstituted cyclopropenes has been developed utilizing an in situ formed copper hydride.

Cobalt‐Catalyzed Diastereo‐ and Enantioselective Hydroalkenylation of Cyclopropenes with Alkenylboronic Acids

“…In the field of catalytic enantioselective functionalization of cyclopropenes, Rh‐catalyzed hydrostannation, hydroboration, hydroformylation, hydroacylation, and Cu‐catalyzed hydroboration, hydronitronylation, carbocupration, carbozincation, carbomagnesiation, hydroallylation, and Fe‐ and Pd‐catalyzed carbozincation, and lanthanide‐catalyzed hydroamination, hydroalkynylation, addition of 2‐methyl azaarenes, and NHC‐catalyzed hydroacylation have been disclosed for enantioselective preparation of various functionalized cyclopropanes (Scheme b). However, introduction of diversified alkenyl groups onto a cyclopropyl ring has been rarely reported despite all the strategies mentioned above .…”

Diastereo- and enantioselective preparation of cyclopropanol derivatives

“…Following the same concept of copper-catalyzed diastereo- and enantioselective carbomagnesiation reaction of cyclopropenes 6 followed now by a selective electrophilic amination reaction, a powerful entry to cyclopropylamines as single diastereoisomer and in excellent enantiomeric ratios could also be achieved (Scheme 7) [89]. However, the enantioselective and catalytic copper-catalyzed carbomagnesiation reaction gave poor enantiomeric ratios for the addition of vinyl, aryl and allyl groups and alternative strategies have been recently developed in our research group [90–92].…”

Synthetic Applications of Cyclopropene and Cyclopropenone: Recent Progress and Developments

“…Almost all of the reports reflected 1,2-syn allylation of cyclopropenes [13] but anti allylation of cyclopropenes remained an unsolved problem. In 2017, Marek's group [14] demonstrated an asymmetric anti hydroallylation of cyclopropenes. This reaction was initiated by in situ generated copper hydride complex and provided the cyclopropyl Cu-intermediate confined by allyl electrophile generated from allyl phosphate 14 provided 2,3-disubstituted anti products 19 in good yield with excellent diastereoselectivity.…”

“…After asymmetric vinylation [13] and allylation [14] of cyclopropenes, the same author also attempted for asymmetric 1,2syn bis-functionalization. They developed a highly enantio and diastereoselective copper-catalyzed carbomagnesiation reaction of unfunctionalized cyclopropene to provide highly substituted cyclopropanes 25 by using various alkyl Grignard reagents.…”