Carbonyl-protected .beta.-lithio aldehydes and ketones via reductive lithiation. A general preparative method for remarkably versatile homoenolate equivalents
摘要:
A general procedure for producing homoenolate equivalents consists of reductive lithiation, induced by 4,4'-di-tert-butylbiphenylide, of carbonyl-protected beta-(phenylthio) carbonyl compounds prepared in turn by thiophenol addition to enones or the alkylation of silyl enol ethers by alpha-chlorothioethers.
Bioinspired Catalytic Conjugate Additions of Thiophenols to α,β-Enones by a Disubstituted Benzoate-Bridged Nickel Mimic for the Active Site of Urease
作者:Way-Zen Lee、Huan-Sheng Tseng、Tzu-Li Wang、Hui-Lien Tsai、Ting-Shen Kuo
DOI:10.1021/om100103u
日期:2010.7.12
te (HL), was prepared to synthesize nickel mimics for the active site of urease. Reaction of the deprotonated L− with Ni(ClO4)2·6H2O afforded a dinickelcomplex, [LNi2(CH3CN)(THF)](ClO4)3 (1), characterized by UV/vis spectroscopy and X-ray crystallography. Addition of urea to an acetonitrile solution of 1 afforded a dinickel urea adduct, [LNi2(urea)2](ClO4)3·2CH3CN (2), which was structurally and spectroscopically
SmI<sub>2</sub>-mediated reductive cyclization of β-arylthio ketones: a facile and diastereoselective synthesis of thiochroman derivatives
作者:Hui Mao、Bing-Xin You、Lie-Jin Zhou、Ting-Ting Xie、Yi-Hang Wen、Xin Lv、Xiao-Xia Wang
DOI:10.1039/c7ob01082f
日期:——
SmI2-mediated reductive cyclization of β-arylthio ketones to generate thiochroman derivatives is not generally observed process and the reported examples are limited to geminal disubstitution in the substrates. The results of the current study show that the cyclization also occurs when other substitution patterns are present, affording a general approach to dihydrothiochroman-ols in good yields and
Highly Efficient Proline Ester-based Nickel Catalysts for Michael Addition of Thiophenols to α,β-Enones
作者:Way-Zen Lee、Chien-Wei Chiang、Girish M. Kulkarni、Ting-Shen Kuo
DOI:10.1002/jccs.201200386
日期:2013.3
Two N3O2 pentadentate ligands, BMPP and BPPP, were prepared for synthesizing highlyefficient nickel catalysts, [Ni(BMPP)(CH3CN)](ClO4)2 (1) and [Ni(BPPP)(CH3CN)](BPh4)(ClO4) (2), for thia‐Michaeladdition of thiophenols to α,β‐enones. X‐ray structures of 1 and 2 revealed that a labile CH3CN molecule was bound to the nickel center of the catalysts. ESI‐MS spectroscopy indicated that thiolate replaced
Asymmetric reduction of aliphatic ketones and acyl silanes using chiral anti-pentane-2,4-diol and a catalytic amount of 2,4-dinitrobenzenesulfonic acid
Aliphatic ketones were reduced to the corresponding secondaryalcohols by using anti-1,3-diol and a catalytic amount of 2,4-dinitrobenzenesulfonic acid (DNBSA) in benzene at reflux. Addition of 1-octanethiol in that media improved the efficiency of the reduction. Asymmetric reduction of aliphatic ketones was performed by using chiral anti-pentane-2,4-diol, and highly asymmetric induction (up to >99%
Indium(I) Iodide-Promoted Cleavage of Dialkyl Disulfides and Subsequent Michael Addition of Thiolate Anions to Conjugated Carbonyl Compounds
作者:Brindaban C. Ranu、Tanmay Mandal
DOI:10.1055/s-2004-825583
日期:——
Indium(I) iodide promotes cleavage of dialkyl disulfides generating thiolate anions which then undergo facile addition to α, β -unsaturated ketones, aldehydes, carboxylic esters and nitriles under neutral conditions producing corresponding β-keto or β-cyano sulfides in high yields. There are several examples of dialkyl/diaryl disulfides and activated alkenes participating in this reaction.