By employing triethylamine as a catalyst, [3 + 2] coupling‐eliminationcascade of α,α‐dicyanoolefins with quinonemonoimines was realized. The reactions afforded various novelpterocarpenanalogues with generally moderate yields (up to 75%). In addition, a plausible reaction mechanism was proposed.
A highly enantioselectivearylation of 3-carboxamide oxoindoles with quinone monoimines is described. Various 3-aryl-3-carboxamide oxindoles with an all-carbon quaternary center were obtained in moderate to good yields (up to 99%) with moderate to good enantioselectivities (up to 98%) in the presence of a bifunctional thiourea-tertiary amine catalyst. The absolute configuration of one product was determined
The first enantioselective dearomative [3+2] annulation of 5-amino-isoxazoles with quinonemonoimines was realized using a chiralphosphoricacid as catalyst. Various novel (bridged) isoxazoline fused dihydrobenzofurans bearing two continuous quaternary stereocenters were achieved in moderate to good yields (up to 94%) with moderate to good enantioselectivities (up to 98% ee). The absolute configurations
Chiral Primary Amine Catalyzed
<i>α</i>
‐Arylation of Simple Ketones via Asymmetric Retro‐Claisen Cleavage
作者:Yanfang Han、Mingying Shi、Xueling Mi、Sanzhong Luo
DOI:10.1002/chem.202202584
日期:2022.12.20
C−C cleavage to arylation. Enantioselective α-arylation of simple aliphatic ketones has been achieved via chiral primary amine catalyzed asymmetric retro-Claisen cleavage involving β-diketones and para-quinone monoimines that facilitates the construction of α-aryl tertiary carbon stereocenters in good yields and high enantioselectivities.