Acylation of N- silylmethyl amines

N-acylation of amines to form amides is one of the most widely studied reaction in organic chemistry. N-acylation reactions of the N-silylmethylamines using a variety of acylating agents are summarized below. 

The first step of this reaction is the activation of the carboxyl moiety. Depending on the type of activating reagent, the intermediate is a stable compound which could be isolated if needed. In the second step, the resulting intermediate reacts with amine. Both the steps can be performed as a one-pot reaction or, with certain types of activating reagents, as either consecutively. 

Compound Solvent Activating Reagent Base ri/r2 °c)f,/ 2.h Yield (%) References  

The reaction, as rule, proceeds in dichloromethane in the presence of triethylamine or Hiinig s base (N,N-diisopropylethylamine). However, amide 125 is formed in good yield (60%) in the absence of solvent and base. The reaction time is not specified by the authors, who wrote A mixture... was stirred at room temperature until no starting material was observable using TLC... (55). Unfortunately, the authors (102) do not report the yield of amide 127 which has been successfiiUy applied in the study of noncovalent interactions in the folded peptoids. 

It has been reported fJJCD that refluxing of a mixture ofN-[(tri-methylsilyl)methyl]benzylamine and butyl formate in benzene leads to the generation in situ of N-benzyl-N-[(trimethylsilyl) methyl] formamide 139. The latter further sequentially converts into N-benzyl-N-[ trimethylsilyl)methyl]-amino]malononi-trile (one-pot synthesis). Unfortunately, amide 139 has not been isolated and characterized, but we believe that, if necessary, this procedure may be performed. 

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