N,N-dialkylcarbamato complexes as precursors for the chemical implantationof metal cations on a silica support. Part 3 - Palladium

Chemical implantation df palladium(II) has been carried but under mild cond itions by reacting trans-Pd(O2CNEt2)(2)(NHEt2)(2) with the silanol groups o f amorphous silica, carbon-dioxide and secondary amine being released in th e process. The palladium-containing silica has been characterized and the c oordination environment of the implanted cation has been defined by C-13 CP MAS NMR, DRIFT and-XPS spectra, and by WAXS measurements. Silica-bonded pa lladium(II) was reduced thermally in. vacuo or with dihydrogen at room temp erature. Catalytic activity in the hydrogenation of cyclohexene was found f or all samples containing the silica-supported reduced palladium; the best results, with rates independent of olefin concentration, were found for the samples treated thermally (200 degrees C) under reduced pressure.