Ordered mesoporous silicas functionalized with alkylsulfonic acid and thiol group pairs have been shown to catalyze the synthesis of bisphenols from the condensation of phenol and various ketones, with activity and selectivity highly dependent on the distance between the acid and thiol. Here, a new route to thiol/sulfonic acid paired catalysts is reported. A bis-silane precursor molecule containing both a disulfide and a sulfonate ester bond is grafted onto the surface of ordered mesoporous silica, SBA-15, followed by simultaneous disulfide reduction and sulfonate ester hydrolysis. The resulting catalyst, containing organized pairs of arylsulfonic acid and thiol groups, is significantly more active than the alkylsulfonic acid/thiol paired catalyst in the synthesis of bisphenol A and Z, and this increase in activity does not lead to a loss of regioselectivity. The paired catalyst has activity similar to that of a randomly bifunctionalized arylsulfonic acid/thiol catalyst in the bisphenol A reaction but exhibits greater activity and selectivity than the randomly bifunctionalized catalyst in the bisphenol Z reaction.

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A promising route for the double carbonylation of aryl iodide derivatives with secondary and primary amines to produce a-ketoamides is described using covalently immobilized palladium complexes on SBA-15 silica. Adequate adjustments of the different reaction parameters (temperature, CO pressure, nature of base, solvent, substrate. . .) to achieve optimal catalyst performance were made using PdCl 2 (PPh 2 ) 2 @SBA-15 as catalytic system. High conversions (up to 80%) and excellent selectivities (up to 96%) for the double carbonylated a-ketoamide products were obtained using K 2 CO 3 as base, MEK or DMF as solvent and a 1 mol% [Pd] catalyst. We also demonstrated that two other palladium hybrid mesoporous materials can be alternatively used, namely PdCl 2 (PCy 2 ) 2 @SBA-15 and PdCl 2 (PNP)@SBA-15, without loss of activity and selectivity. Finally, catalyst recycling of PdCl 2 (PPh 2 ) 2 @SBA-15 showed that the catalyst could be reused for up to 3 cycles without affecting catalyst performance.Scheme 1 Palladium-catalysed double carbonylation of aryl halide to a-ketoamides.