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Under solvent-free conditions, thiosalicylic acid (2) efficiently self-promotes the thiolysis of 1,2-epoxides 1, anti-stereoselectively and generally totally beta-regioselectively. The resulting beta-hydroxysulfide products 3 have been obtained in very good yields. Benzo[e]1,4-oxathiepin-5-ones 4 have been easily prepared in a regio- and diasteroselective manner and in satisfactory yields under SFC by a one-pot protocol including nucleophilic ring opening of 1,2-epoxides 1 by thiosalicylic acid (2) and thermally induced lactonization of beta-hydroxy arylsulfides 3. Solvent-free condition and the absence of any catalyst make this procedure atom-economical and environmentally friendly.

Abstract: This contribution reports the results obtained in the definition of a catalytic method for the nucleophilic ring opening of epoxides by activated methylenes promoted by a polymer-supported base. The attention has been focused on the use of polymer supported bases and the best results have been obtained by using 4-(dimethylamino)pyridine (PS-DMAP) and 2-tert-butylimino-2-diethylamino-1,3-dimethyl-perhydro-1,3,2-diazaphosphorine both on polystyrene (PS-BEMP). Solvent-free conditions has been essential for reaching a sufficient reactivity to realize this process, in fact when a reaction medium is used, the processes are almost unfeasible. [Copyright &y& Elsevier]

The Zn(OTf)2-SDS-bipyridine 1 system has proved to be an effective catalyst in water for the desymmetrization of epoxides 2a-d by anilines 3a-d. After obtaining comparable results by using Sc(III)-SDS and Zn(II)-SDS systems in the case of 2a and 3a, we have explored the enantioselective ring opening of small epoxides for which water has never been used as reaction medium. Up to date the 85% ee obtained in the case of cyclohexene oxide 2b with amines 3a and 3d are very good results and are the highest values obtained in water as reaction medium. [ABSTRACT FROM AUTHOR]

Zirconium dodecyl sulfate [Zr(DS)4] is an efficient catalyst for the aminolysis of epoxides in water at pH 5.0. Epoxides and anilines were used and the corresponding β-amino alcohols were isolated in generally high regioselectivity and excellent yields. [ABSTRACT FROM AUTHOR]

Thiolysis of a variety of 1,2-epoxides in water at 30 °C and pH 7.0 is strongly accelerated by ZnCl[sub 2] (10 mol %) except when amino- and carboxythiophenol are used. The aqueous medium and the catalyst were recovered and reused in various runs without affecting the efficiency of the process. [ABSTRACT FROM AUTHOR]

β-Amino alcohols N-2′-pyridylmethyl substituted 3 have been prepared in excellent yields under mild conditions by the first Lewis acid-catalyzed aminolysis of 1,2-epoxides 1 with the bihaptic amine 2-picolylamine (2) with use of 5 mol % of Al(OTf)3 under solvent-free conditions. As a representative of a new class of ionic liquids, cis-5-[(4′-methylphenyl)sulfonyl]-1,2,3,4,4a,5,6,11a-octahydropyrido[1,2-a]quinoxalin-11-ium methanesulfonate (6) and its chloride derivative 7 have been synthesized under environmentally friendly conditions by the one-pot aminolysis of cyclohexene oxide (1a) with 2 and intramolecular cyclization of the resulting 2-[(pyridin-2′-yl)methylamino]cyclohexanol (3a). [ABSTRACT FROM AUTHOR]

Thiolysis of alkyl- and aryl-1,2-epoxides was investigated under solvent-free conditions in the presence of Lewis and Brønsted acid and base catalysts (InCl3, p-TsOH, n-Bu3P, K2CO3). Five mol% of catalyst was sufficient and the best results were obtained by using InCl3 and K2CO3. β-Hydroxy sulfide was isolated in excellent yields. [Copyright &y& Elsevier]

Investigates the ring-opening reaction of epoxides with sodium azide in water. Azidolysis by sodium azide of epoxycyclohexane in aqueous medium; Azidolysis by sodium azide of epoxides in aqueous medium at 30 degrees Centigrade; Regioselectivity of the reaction under acidic conditions.