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.
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.
Chiral Sodium Phosphate Catalyzed Enantioselective 1,4-Addition of TMSCN to Aromatic Enones
作者:Fu-Xue Chen、Jingya Yang、Shaoxiang Wu
DOI:10.1055/s-0030-1258817
日期:2010.11
A facile enantioselective 1,4-addition of TMSCN to aromatic enones has been developed using chiral sodium phosphate. Thus, in the presence of 20 mol% of sodium salt generated in situ from (R)-3,3′-di(1-adamantyl)-1,1′-binaphthyl-2,2′-diylphosphoric acid and NaOH, β-cyano ketones were obtained in high yield (86-96%) and up to 72% ee within three hours at 80 ËC in toluene.
Highly Efficient Syntheses of β-Cyanoketones via Conjugate Addition of Me3SiCN to Aromatic Enones
作者:Jingya Yang、Fuxue Chen
DOI:10.1002/cjoc.201090182
日期:——
An efficient 1,4‐addition of Me3SiCN to aromatic enones has been achieved with excellent yields (91% –99%) using CsF (1 mol%) as the catalyst and H2O (4 equiv.) as the additive in refluxing dioxane within 7 h. The perfect regioselectivity is proposed accounting from H2O‐facilitated reversion of the 1,2‐adduct in the presence of CsF and subsequent irreversible 1,4‐addition reaction.