Preparation of 2-Zincio-1,3-Dithianes and Di(1,3-dithian-2-yl)zinc and Their Reaction with Highly Functionalized Halides and α,β-Unsaturated Carbonyl Compounds
作者:Vanda Cerè、Silvia De Angelis、Salvatore Pollicino、Alfredo Ricci、Ch. Kishan Reddy、Paul Knochel、Gérard Cahiez
DOI:10.1055/s-1997-1324
日期:1997.10
The title compounds were obtained by simple transmetallation of the corresponding lithium derivatives with ZnCl2 or ZnBr2. Contrary to 2-lithio-1,3-dithianes, 2-zincio-1,3-dithianes can react with a number of electrophiles bearing reactive functional groups to afford highly substituted 1,3-dithianes in satisfactory to excellent yields. The synthesis of the new organozinc derivative, di(1,3-dithian-2-yl)zinc, which effectively adds to enones, is also reported.
Double Conjugate Addition of Dithiols to Propargylic Carbonyl Systems To Generate Protected 1,3-Dicarbonyl Compounds
作者:Helen F. Sneddon、Alexandra van den Heuvel、Anna K. H. Hirsch、Richard A. Booth、David M. Shaw、Matthew J. Gaunt、Steven V. Ley
DOI:10.1021/jo052514s
日期:2006.3.31
methoxide to a wide variety of propargylic carbonyl containing compounds. The products of these reactions are differentiated, 1,3-dicarbonyl systems useful for various synthesis programs. By judicious use of hydroxylated substrates tandem cyclization occurs to afford tetrahydropyran lactols or, in the case of hydroxy-substituted propargylic esters, lactones. The corresponding amino-substituted propargylic
Double Michael addition of dithiols to acetylenic carbonyl compounds under the influence of molecular sieve and dimethyl sulfoxide
作者:Tomoko Kakinuma、Takeshi Oriyama
DOI:10.1016/j.tetlet.2009.11.002
日期:2010.1
Double Michael addition of dithiols such as 1,3-propanedithiol and 1,2-ethanedithiol to α,β-acetylenic carbonyl compounds in the presence of molecular sieve and dimethyl sulfoxide proceeds very smoothly to afford the corresponding β-keto 1,3-dithianes and β-keto 1,3-dithiolanes, respectively, in good to high yields.
Oxidative Generation of Thioalkyl Cations from 2-Tributylstannyl-1,3-dithianes and 1-(Tributylstannyl)alkyl Sulfides and Their Reactions with Olefinic Nucleophiles
作者:Koichi Narasaka、Noriyoshi Arai、Tatsuo Okauchi
DOI:10.1246/bcsj.66.2995
日期:1993.10
2-Tributylstannyl-1,3-dithianes and 1-(tributylstannyl)alkyl sulfides are oxidized with ammoniumhexanitratocerate(IV) or ferrocenium hexafluorophosphate to generate their cation radicals, which dissociate into the carbocations and tributylstannyl radical. The carbocations thus generated react with olefinic nucleophiles to afford the corresponding addition products in good yield.
Generation of Cation Radicals from 2-Tributylstannyl-1,3-dithianes and Their Reaction with Olefins
作者:Koichi Narasaka、Tatsuo Okauchi、Noriyoshi Arai
DOI:10.1246/cl.1992.1229
日期:1992.7
Oxidation of 2-tributylstannyl-1,3-dithianes with metallic oxidants generates reactive species such as 1,3-dithian-2-yl radical and/or cation by eliminating the stannyl group. Those intermediates react with olefins to give the intermolecular addition products.