Molecular sieves with three-dimensional framework structures find many applications in catalysis. [1, 2] A comprehensive and fundamental understanding of the product selectivity associated with these catalytic processes remains a formidable challenge of considerable practical significance. [3] Herein we focus on conversion reactions of alkanes. We demonstrate that molecular sieves favor the formation of reaction intermediates that have a shape commensurate with their pore shape.
Bis(bidentate) catecholamide ligands (Scheme 2) were synthesized according to previously published procedures. [26] Libraries were obtained following a simple procedure: H 4 -L 2 (33.1 mg, 0.077 mmol), H 4 -L 3 (39.0 mg, 0.077 mmol), Et 4 NCl, (4.3 mg, 0.026 mmol), and [Ga(acac) 3 ] (acac acetylacetonate) (37.1 mg, 0.102 mmol) were suspended in methanol (20 mL). A 0.5 n NaOH solution (620 mL) in H 2 O was added slowly, and a clear solution was obtained. After the mixture had been stirred for 2 h, the solvent was reduced to 4 mL, and excess acetone was added to precipitate the product, which was collected by ultracentrifugation, washed with acetone and dried (quantitative yields). The same library was obtained by mixing solutions of [Ga 4 L 2 6 ' (Et 4 N)] 11Γ and [Ga 4 L 3 6 ' (Et 4 N)] 11Γ at pD 7.5 after heating for several hours at 60 8C.