摘要： Transformation of various kinds of nitriles into the corresponding amides or amide salts was performed in good yields by the addition of two equiv of chlorotrimethylsilane and three equiv of water at 0℃ to room temperature. Hydrogen halide generated in situ by TMSX and water is an important reaction especially when HX is needed in requisite amount and under dry reaction conditions. As part of our endeavor to utilize HX thus generated, we have found TMSC1 and water can be used for transformation of nitriles into amides under very mild reaction conditions and with satisfactory yields. Interestingly, under the condition of hydration of nitrile, ester of carboxylic acid remains intact. Although there are several reports in the literature to bring about the same transformation, however, a new approach is still significant and needed. Moreover, most of the reported methods have not been proven in general and practical in scope. This paper reports the hydration of a series aliphatic as well as aromatic nitriles into amides at 0℃ to room temperature for only two to four hours. Solvent is not needed in this transformation. Attempts to use THF, MeNO₂, or CH₂Cl₂ as the solvent results in poor yields. Protonation of the nitrile by HCl, generated in situ from TMSC1 and half equiv of H₂O, and followed by nucleophilic attack by another equiv of H₂O to form the amide salt seems to be the possible pathway for this reaction. Ideally, the molar ratio for RCN/TMSC1/H₂O is 1:1:1.5. Use of little excess of the reagents (0.2 to 0.5 equiv) leads to completion of this reaction in 10 to 12 h. To compensate the escape of HCl generated in situ, one more equiv of HCl is generally used in this reaction. No further hydrolysis of amide to the carboxylic acid was observed in the presence of one more equiv of water.

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