Silylation process

An improved process for the trimethylsilylation of organic compounds with at least one active hydrogen atom with hexamethyldisilazane, the improvement comprising effecting the reaction in the presence of 0.001 to 10 mole percent of a catalyst of the formula

• X--NH--Y I
• wherein X and Y are individually an electron-withdrawing group or when X is an electron-withdrawing group, Y is selected from the group consisting of hydrogen and trialkylsilyl of 1 to 6 carbon atoms or X and Y together with the nitrogen atom to which they are attached form a cyclic electron-withdrawing group the electron-withdrawing group being selected from the group consisting of ##STR15## wherein R.sub.1 and R.sub.2 are individually selected from the group consisting of alkyl of 1 to 6 carbon atoms optionally substituted with at least one halogen, aryl optionally substituted with at least one member of the group consisting of halogen, alkyl and alkoxy of 1 to 6 carbon atoms and nitro, alkoxy of 1 to 6 carbon atoms, aryloxy optionally substituted with at least one member of the group consisting of halogen, alkyl, nitro and ##STR16## R.sub.3 and R.sub.4 are individually selected from the group consisting of hydrogen, alkyl of 1 to 6 carbon atoms and trialkylsilyl of 1 to 6 carbon atoms and the electron-withdrawing group which forms a cyclic system together with the nitrogen atom to which they are attached have the formula --A--Z--B wherein A is ##STR17## B is selected from the group consisting of ##STR18## and Z is selected from the group consisting of alkylene of 1 to 6 carbon atoms, alkenylene of 2 to 6 carbon atoms and arylene, all optionally substituted with at least one member of the group consisting of halogen and alkyl.