α-Diazosulphones and related compounds from the base-induced cleavage of α-diazo-β-ketosulphones
作者:D. Hodson、G. Holt、D. K. Wall
DOI:10.1039/j39680002201
日期:——
sulphonylformaldehyde hydrazones (70—80%), a previously unknown class of compounds, which arose by hydrolysis of the first formed phosphazine. The acylsulphonyldiazomethanes were prepared by the action of toluene-p-sulphonylazide and triethylamine on β-ketosulphones in 60% aqueous ethanol. If the diazoketosulphone is retained in solution and the reaction period prolonged, sulphonylformaldehyde hydrazones may be
approach to the preparation of α-diazo-β-ketosulfones from sulfonyl chlorides is described. It involves the conversion of the sulfonyl chloride to sodium sulfinate, alkylation of the latter with α-haloketones followed by diazo transfer using the ‘sulfonyl-azide-free’ (‘SAFE’) protocol in aqueous medium. The simple and expedient method relies on readily available starting materials and provides facile
A Cu‐catalyzed cascade oxidative radical process of β‐keto sulfones with alcohols has been achieved by using oxygen as an oxidant. In this reaction, β‐keto sulfones were converted into sulfinate esters under the oxidative conditions via cleavage of C−S bond. Experimental and computational studies demonstrate that a new pathway is involved in this reaction, which proceeds through the formation of the
Diaminomethylidene derivatives of β-oxo sulfones as potential reagents in heterocyclic synthesis and chelating ligands
作者:V. A. Voronkova、S. V. Baranin、M. A. Prezent、L. S. Vasil’ev、V. A. Dorokhov
DOI:10.1007/s11172-010-0337-3
日期:2010.10
the reaction products under the action of MeONa in MeOH gives N,N′-unsubstituted diaminomethylidene derivatives of β-oxo sulfones (acyl(R-sulfonyl)ketene aminals), which can be used as reagents for heterocyclicsynthesis and as chelating ligands. The syntheses of 2-amino-3-arylsulfonylpyridin-4(1H)-ones and 5-sulfonylcytosine derivatives are presented as examples.
A chemo-enzymatic synthesis of chiral secondary alcohols bearing sulfur-containing functionality
作者:Qihui Chen、Ke Wang、Chengye Yuan
DOI:10.1039/b820192g
日期:——
A facile method for the preparation of chiral secondary alcohols bearing a sulfur-containing functionality using a chemo-enzymatic approach is described, with the aid of baker’s yeast and Candida Antarctica lipase B. A complete set of four stereoisomers of two substituted phenylsulfinylpropan-2-ols were synthesized from β-sulfinyl ketones with excellent enantioselectivity for the first time.
本文介绍了一种利用化学酶法、借助面包酵母和南极念珠菌脂肪酶 B 制备具有含硫官能团的手性仲醇的简便方法,首次以 β-亚磺酰基酮为原料合成了两取代苯基亚磺酰基丙-2-醇的一整套四种立体异构体,并具有极佳的对映选择性。