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A series of esters of R-tetrahydrothiazo-2-thione-4-carboxylic acid[R-TTCA] was synthesized by direct esterification of R-TTCA with alcohols(CH3OH,C2H5OH,n-C3H7OH,i-C3H7OH,n-C4H9OH,sec-C4H9OH)in the presence of TiCl4 as the catalyst at room temperature without using any other solvent or dehydrant in high yields,91.6%-99.1% for primary alcohols and 55%- 80% for secondary alcohols.The catalyst has a strong chemoselective activity for the esterification of primary alcohols with R-TTCA in the presence of secondary alcohols.Owing to high yield,high chemoselectivity,and mild conditions used,this is an efficient method for the esterification of primary alcohols with R-TTCA.
A series of esters of R-tetrahydrothiazo-2-thione-4-carboxylic acid [R-TTCA] was synthesized by direct esterification of R-TTCA with alcohols (CH3OH, C2H5OH, n- C3H7OH, i- C3H7OH, n- C4H9OH, sec-C4H9OH) in the presence of TiCl4 as the catalyst at room temperature without using any other solvent or dehydrant in high yields, 91.6% -99.1% for primary alcohols and 55% -80% for secondary alcohols. The catalyst has a strong chemoselective activity for the esterification of primary alcohols with R-TTCA in the presence of secondary alcohols. Out to high yield, high chemoselectivity, and mild conditions used, this is an efficient method for the esterification of primary alcohols with R-TTCA.