Highly Efficient Cs2CO3-Catalyzed 1,4-Addition of Me3SiCN to Enones with Water as the Additive
作者:Fu-Xue Chen、Jingya Yang、Yongbin Shen
DOI:10.1055/s-0029-1218653
日期:2010.4
A facile and efficient 1,4-addition of Me3SiCN to enones has been achieved with perfect regioselectivity using Cs2CO3 as catalyst. Thus, with 0.5 mol% of Cs2CO3 and 4 equivalents of H2O as the additive excellent yields (81-99%) of β-cyanoketones are obtained within one to five hours. Both aromatic and aliphatic enones are found suitable substrates for this protocol.
nucleophilic addition involves removal of the cyano group linked to active methylene by the action of KF, and direct addition to enones. The reaction's capability for nucleophilic attack is F− > CN− in DMF. The use of low-toxicity reagents hints that the reaction is more environmentally friendly than traditional approaches.
多米诺亲核加成反应用于四组分Al 2 O 3催化的多取代β-氰基丙烷-1-酮的环保合成。多米诺亲核加成反应包括通过KF的作用除去与活性亚甲基连接的氰基,然后直接加成烯酮。该反应的亲核攻击能力是F - > CN -在DMF。使用低毒性试剂提示该反应比传统方法对环境更友好。
Conjugate Hydrocyanation of Chalcone Derivatives Using Ethyl Cyanoacetate as an Organic Cyanide Source
作者:Zheng Li、Junjun Yin
DOI:10.1002/cjoc.201600860
日期:2017.7
The conjugate hydrocyanation of chalcone derivatives using ethyl cyanoacetate as an organic cyanide source at room temperature under open air and transition metal‐free conditions was described. The protocol has advantages of using relatively cheap, less toxic, stable and easy‐to‐handle cyanating reagent, high yield, and mild reaction condition.
Cyano-borrowing reaction: nickel-catalyzed direct conversion of cyanohydrins and aldehydes/ketones to β-cyano ketone
作者:Zhao-Feng Li、Qian Li、Li-Qing Ren、Qing-Hua Li、Yun-Gui Peng、Tang-Lin Liu
DOI:10.1039/c9sc00640k
日期:——
nickel-catalyzed, high atom- and step-economical reaction of cyanohydrins with aldehydes or ketones via an unprecedented “cyano-borrowing reaction” has been developed. Cleavage of the C–CN bond of cyanohydrins followed by aldol condensation and conjugate addition of cyanide to α,β-unsaturated ketones proceeded to deliver a range of racemic β-cyano ketones with good to high yields. The practical procedure
Cyanation of α,β-unsaturated enones by malononitrile in open air under metal-catalyst-free conditions
作者:Shaoxia Lin、Ying Wei、Fushun Liang
DOI:10.1039/c2cc35528k
日期:——
Cyanation of α,β-unsaturated enones by employing malononitrile as the organic cyanation source has been disclosed, which proceeds efficiently at room temperature in open air under metal-catalyst-free conditions.