Reaction of dichloroketone with cyclic thioketals of .alpha.,.beta.-cycloalkenones: synthesis of 1,7-dithiacycloalk-5-en-2-one derivatives by a four-carbon cycloenlargement
Chemoselective (Trans)thioacetalization of Carbonyl Compounds with a Reusable Lewis Acid-Surfactant-Combined Copper Bis(dodecyl sulfate) Catalyst in Water
A Lewis acid-surfactant-combined copper bis(dodecyl sulfate) [Cu(DS)2] catalyst served as an efficient and reusable catalyst for the thioacetalization and transthioacetalization of carbonyl compounds and O,O-acetals in water at room temperature. Some of the major advantages of this procedure are high chemoselectivity, ease of operation and purification without any organic solvent, and high yields.
Catalytic carbon–sulfur bond formation by amphoteric vanadyl triflate: exploring with thia-Michael addition, thioacetalization, and transthioacetalization reactions
作者:Chien-Tien Chen、Yow-Dzer Lin、Cheng-Yuan Liu
DOI:10.1016/j.tet.2009.10.012
日期:2009.12
A series of thiols have been examined as protic nucleophiles for Michael-type additions to alpha,beta-unsaturated carbonyls as well as double nucleophilic condensations with aldehydes, ketones, and acetals catalyzed by amphoteric, water-tolerant vanadyl triflate under mild and neutral conditions. The newly developed C-S bond formation protocols were carried out smoothly in good to high yields in a highly chemoselective manner. (C) 2009 Elsevier Ltd. All rights reserved.
ROSINI G.; SPINETTI G. G.; FORESTI E.; PRADELLA G., J. ORG. CHEM., 1981, 46, NO 11, 2228-2230
作者:ROSINI G.、 SPINETTI G. G.、 FORESTI E.、 PRADELLA G.
DOI:——
日期:——
Entirely Solvent-Free Procedure for the Synthesis of Distillable 1,3-Dithianes Using Lithium Tetrafluoroborate as a Reusable Catalyst
作者:Tsuneo Sato、Kiyoshi Kazahaya、Shinya Tsuji
DOI:10.1055/s-2004-829084
日期:——
Treatment of various types of aldehydes and ketones with 1,3-propanedithiol in the presence of a catalytic amount of lithium tetrafluoroborate at 25 °C under solvent-free conditions followed by direct purification by distillation of the resulting mixture affords the corresponding 1,3-dithianes in good to excellent yields. Chemoselective protection of keto aldehydes is also successfully achieved over the catalyst. The catalyst can be recovered and reused.
Reaction of dichloroketone with cyclic thioketals of .alpha.,.beta.-cycloalkenones: synthesis of 1,7-dithiacycloalk-5-en-2-one derivatives by a four-carbon cycloenlargement
作者:Goffredo Rosini、Giancroce G. Spineti、Elisabetta Foresti、Gabriele Pradella