Asymmetric Cyanation of Aldehydes, Ketones, Aldimines, and Ketimines Catalyzed by a Versatile Catalyst Generated from Cinchona Alkaloid, Achiral Substituted 2,2′-Biphenol and Tetraisopropyl Titanate
Full investigation of cyanation of aldehydes, ketones, aldimines and ketimines with trimethylsilyl cyanide (TMSCN) or ethyl cyanoformate (CNCOOEt) as the cyanide source has been accomplished by employing an in situ generated catalyst from cinchona alkaloid, tetraisopropyl titanate [Ti(OiPr)4] and an achiral modified biphenol. With TMSCN as the cyanide source, good to excellent results have been achieved
Efficient synthesis in water of mixed carbonates of cyanohydrins from aromatic aldehydes
作者:Torres Domínguez Héctor Manuel、Maldonado Luis Ángel、Le Lagadec Ronan
DOI:10.1016/j.tetlet.2019.151414
日期:2020.1
An efficient preparation of cyanohydrin ethyl carbonates via cyanocarbonation of aromatic and hetero-aromatic aldehydes with sodium cyanide and ethyl chlorocarbonate using commercial surfactants (5 mol %) in aqueous media at low temperature afforded almost quantitative isolated yields (≥ 94 %) in 30 minutes. Aromaticaldehydes bearing electron-donating as well as electron-withdrawing groups have been
Consecutive reactions to construct tricarbonyl compounds and synthetic applications thereof
作者:Diego Madroñero、Cesar A. Mujica-Martinez、Alfredo Vázquez
DOI:10.1039/d1ra05187c
日期:——
Lithium anions derived from O-carbonate-protected cyanohydrins undergo conjugate addition to cycloalkenones with the concomitant transfer of the alkoxycarbonyl group to produce tricarbonyl compounds. These products offer numerous possibilities for further elaboration. The synthetic potential of the cascade products was demonstrated by forming bicyclic and tricyclic systems through intramolecular condensation
Neutral π-Nucleophile-Catalyzed Cyanation of Aldehydes and Ketones
作者:Shi-Kai Tian、Xiu Wang
DOI:10.1055/s-2007-980366
日期:2007.6
1-Methoxy-2-methyl-1-(trimethylsiloxy)propene, a neutral Ï-nucleophile, was found to be able to efficiently catalyze the cyanation (cyanosilylation and cyanocarbonation) of various aldehydes and ketones, and this study provided the first illustration of using a neutral Ï-nucleophile for the development of synthetically useful organocatalysis.
A novel phosphine-promoted intramolecular acylcyanation of alpha-substituted activated alkenes has been developed, which provides a unique access to densely functionalized acyclic ketones bearing beta-quaternary carbon centers with a remarkable feature that both alpha- and beta-positions of activated alkene are functionalized.