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A new potentially catalytic material has been developed by partial recrystallization of the porewall of MCM-41. Recrystallization is induced by impregnation of MCM-41 with tetrapropylammonium hydroxide followed by a hydrothermal treatment. This procedure resulted in the formation of small particles of approximately 3 nm, which can be observed with TEM. The fact that the formation of these particles resembles the first stages of ZSM-5 formation and the fact that a templating material is used, which is also frequently applied in the synthesis of ZSM-5, suggest that the 3 nm particles have a ZSM-5 structure. Furthermore, 13 C NMR on recrystallized MCM-41 shows a split-up of the methyl signal of TPA, which is also known to be present in as-synthesized ZSM-5. After calcination of the recrystallized material the small crystallites could no longer be observed, although IR measurements show still some ZSM-5-like acidity to be present. Other, milder calcination routes should be developed in order to preserve the ZSM-5 crystallites. Another stability problem encountered concerns the stability of the MCM-41 since the hydrothermal treatment severely damaged the framework. It was found that the use of a template molecule, hexadecylamine, to support the framework during the recrystallization was beneficial.

Reaction of N-ligated methylpalladium(II) alkoxide and aryloxide complexes [Pd(Me)(OR)(N ~ N)] (R = Ph, CH(CF3)2; N ~ N = trneda (N, N,N', N'-tetramethylethylenediamine) or bpy (2,2'-bipyridyl)) with carbon monoxide produces the corresponding methylesters in high yields. The insertion takes place either into the Pd-Me bond (aryloxide complexes) or into the Pd-OR bond (alkoxide complexes). Methylpalladium(II) methoxide complexes [Pd(Me)(OMe)(N ~ N)] (N ~ N = tmeda, bpy) have been generated in situ by aryloxide-or alkoxide-methanol exchange reactions for which the equilibrium constants have been determined. The bpy-ligated methylpalladium methoxide complex undergoes insertion of CO producing either a methylpalladium methoxycarbonyl complex [Pd(Me)(CO2Me)(bpy)] (at -60°C) or an acylpalladium methoxycarbonyl complex [Pd(COMe)(CO2Me)(bpy)] (at -25°C); both carbonylated species could be isolated and characterized at low temperature.