33266-07-8Relevant articles and documents
Chiral dithiolane sulphoxides: An efficient stereoselective synthesis of (R) and (S)-3-benzoyloxy-2-butanone
Barros,Barros, M. Teresa,Leitao,Leitao, Alcino J.,Maycock,Maycock, Christopher D.
, p. 6537 - 6540 (2007/10/02)
The effect of the addition of water on the asymmetric oxidation of an acyl dithiane and an acyl dithiolane has been studied. The use of enantiomerically pure dithiolane sulphoxides is demonstrated in a highly selective synthesis (R)-3-benzoyloxy-2-butanone which depends upon a diastereoselective ketone reduction.
Efficient hydrolysis of dithioacetals by the N-fluoro-2,4,6-trimethylpyridinium triflate-water system
Kiselyov,Strekowski,Semenov
, p. 2151 - 2158 (2007/10/02)
Dithioacetals including 1,3-dithianes and 1,3-dithiolanes are efficiently cleaved by the title reagent system to the parent carbonyl compounds. The cleavage of diprotected symmetrical α-diketones and p-phenylenediketones gives monoketones in good yields. Amide, 1,3-dioxolane, disulfide, ester, ether, hydroxy, nitrile, nitro, and sulfide functions are relatively stable under the cleavage conditions but thiols are oxidized to disulfides.
Synthesis of 2,3-dihydro-1,4-dithiins and 2-alkylidene-1,4-dithianes by 1,2-sulfur migration in 2-(1-hydroxyalkyl)-1,3-dithiolanes
Afonso,Barros,Godinho,Maycock
, p. 575 - 580 (2007/10/02)
2,3-Dihydro-1,4-dithiins and the isomeric 2-alkylidene-1,4-dithianes were synthesized from 1,2-diketones and alkyl pyruvates by kinetically controlled ring expansion of 2-(1-hydroxyalkyl)-1,3-dithiolanes with p-toluenesulfonyl chloride in pyridine. In addition, 2,3-dihydro-1,4-dithiins, the thermodynamic products, were formed exclusively by using p-toluenesulfonic acid in refluxing benzene. The 2-alkylidene-1,4-dithianes were readily isomerised to the corresponding 2,3-dihydro-1,4-dithiins. Similarly, 2,3-dimethyl-6,7-dihydro-5H-1,4-dithiepine and (+)-2-methylene-3-methyl-1,4-diethiepane were obtained from 2-[(S)-1-hydroxyethyl]-2-methyl-1,3-dithiane.
Preparation of Some Oxa- and Thia-decalins and -propellanes. Barriers to Conformational Interconversion
Fjeldskaar, Inger Reidun,Skatteboel, Lars
, p. 410 - 417 (2007/10/02)
Reactions of 5,6-dihydro-2,3-dimethyl-1,4-dioxin, -1,4-oxathiin and -1,4-dithiin with bromine in the presence of 1,2-ethanediol, 2-mercaptoethanol and 1,2-ethanedithiol, respectively, afforded, in most cases, high yields of the corresponding oxa- and thia-decalins as cis-isomers only.Similar reactions of the bicyclic dihydrodioxins, 2,5-dioxabicyclodec-1(6)-ene and the sulfur analogues gave the corresponding propellanes in high yields.The barriers to conformational interconversion were obtained from variable temperature NMR spectra.Other examples of propellanes were obtained; addition of dihalocarbenes to the bicyclic dihydrodioxins furnished the corresponding dihalocyclopropane derivatives, and the photochemical addition of benzophenone gave the expected oxetane.
Comparative radioprotective activity of various pentagonal compounds with two heteroatomes
Robbe,Fernandez,Dubief,et al.
, p. 235 - 243 (2007/10/02)
Various heterocyclic compounds with two heteroatomes were synthesized and their potential radioprotective activity was tested. This study shows the interest of phenylthiazolidines derivatives in chemical radioprotection.
The Reaction of 2-Ethoxy-1,3-oxathiolane with Carbonyl Compounds in the Presence of ZnCl2 or HgCl2
Tanimoto, Shigeo,Jo, Shigeo,Sugimoto, Toyonari,Okano, Masaya
, p. 3237 - 3238 (2007/10/02)
In the reaction of 2-ethoxy-1,3-oxathiolane with carbonyl compounds in the presence of ZnCl2 or HgCl2, it has been found that only the breaking of the endocyclic bond (C-O or C-S bond) occurs, while the breaking of the exocyclic C-O bond to give the 1,3-o
