An environmentally benign protocol that affords propargylic sulfones containing highly congested carbon centers from easily accessible alcohols and sulfinic acids with water as the only byproduct is reported. The reaction proceeded via an in situ dehydrative cross-coupling process by taking advantage of the synergetic actions of multiple hydrogen bonds rather than relying on an external catalyst and/or
BINOL−Salen-Catalyzed Highly Enantioselective Alkyne Additions to Aromatic Aldehydes
作者:Zi-Bo Li、Lin Pu
DOI:10.1021/ol0498139
日期:2004.3.1
BINOL-Salen compound (-)-1 can catalyze the addition of both aryl- and alkylalkynes to aromatic aldehydes at room temperature with high enantioselectivity (86-97% ee). The conditions for this catalytic process are both mild and simple. Unlike most other BINOL-based catalysts, using ligand (-)-1 not only avoids heating or cooling but also does not require the addition of Ti(O(i)Pr)(4).
A novel calcium-catalyzed in situ dehydrative cross-coupling reaction of propargylicalcohols with 1,3-dicarbonyl compounds was developed. This catalytic system can suppress the competitive Meyer–Schuster rearrangement, control regioselectivity, and enable the desired process to occur under solvent-free conditions at room temperature with water as the only byproduct. A variety of vicinal tertiary and
Rhodium-Catalyzed [4 + 1] Cyclization via C–H Activation for the Synthesis of Divergent Heterocycles Bearing a Quaternary Carbon
作者:Xiaowei Wu、Haitao Ji
DOI:10.1021/acs.joc.8b00397
日期:2018.4.20
development of an efficient approach to construct fused polycyclic systems bearing a quaternarycarbon center represents a great challenge to synthetic chemistry. Herein, we report a Rh(III)-catalyzed [4 + 1] annulation of propargyl alcohols with various heterocyclic scaffolds under an air atmosphere. Diverse fused heterocycles containing a quaternarycarbon center were obtained in moderate to good
Ruthenium-Catalyzed Redox-Neutral [4 + 1] Annulation of Benzamides and Propargyl Alcohols via C–H Bond Activation
作者:Xiaowei Wu、Bao Wang、Shengbin Zhou、Yu Zhou、Hong Liu
DOI:10.1021/acscatal.7b00031
日期:2017.4.7
transition-metal-catalyzed cycloaddition reactions, in which they generally serve as two-carbon reaction partners. Herein, we report ruthenium(II)-catalyzed redox-neutral [4 + 1] annulation of benzamides and propargyl alcohols, in which propargyl alcohols act as one-carbon units. This synthetic utility of propargyl alcohols led to a series of potentially bioactive N-substituted quaternary isoindolinones