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An efficient, simple, and green four-component reaction for synthesizing 1,2,4,5-tetrasubstituted imidazoles is developed. In present work exploring the use of Samarium triflate as a heterogeneous catalyst for the four-component reaction of aldehydes, aromatic amines, benzil, and ammonium acetate. The current approach offers many advantages, such as excellent yields, shortening of reaction time, reusability of catalyst, and use of mild reaction conditions. [ABSTRACT FROM AUTHOR]

A facile synthetic method for benzothiazoles and benzoxazoles comprising the reaction of corresponding 2-aminothiophenol and 2-aminophenol with various substituted aromatic carboxylic acids using Samarium(III) triflate as a catalyst has been described. The advantages of the method are short reaction times and aqueous reaction media and easy work-up. The catalysts can be recovered for the subsequent reactions and reused without any appreciable loss of efficiency. [ABSTRACT FROM AUTHOR]

A simple, green, and efficient method is presented for the synthesis of benzoxazoles and benzothiazoles from reaction of oaminophenols, o-aminothiophenols, and aliphatic or aromatic aldehydes using samarium triflate as a reusable acid catalyst under mild reaction conditions in aqueous medium [ABSTRACT FROM AUTHOR]

One-pot synthesis of benzimidazole compounds from ortho-phenylenediamine and a variety of aldehydes was developed under mild reaction conditions. All the reactions were carried out in the presence of samarium triflate (10 mol%) in acetonitrile at room temperature. [ABSTRACT FROM AUTHOR]

Abstract: The oxiranes undergo rapid ring opening reaction with amines catalyzed by samarium triflate under mild reaction conditions. The reactions were carried out at below room temperature to afford the corresponding β-amino alcohols in excellent yields and high regioselectivity. This protocol has been applied for the synthesis of various β-blockers. [Copyright &y& Elsevier]

The cycloaddition of 2- or 2,3-substituted 1-thia- and 1-thia-3-aza-4-dimethylamino-buta-1,3-dienes with various dienophiles in the presence of a Lewis acid provides a rapid and diastereoselective access to the 3,4-dihydro-2H-thiopyran and 5,6-dihydro-4H-[1,3]thiazine backbones. The generally observed trans relationship between the two newly created strereogenic centres was demonstrated to be the expression of a thermodynamic control of the reaction. The use of chiral dienophile derived from chiral oxazolidin-2-ones allowed us to prepare enantiopure 5,6-dihydro-4H-[1,3]thiazines and 3,4-dihydro-2H-thiopyrans. In the asymmetric synthetic process the chiral auxiliary removal step was best accomplished in the presence of samarium triflate in methanol. [Copyright &y& Elsevier]