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Zeolite Beta: The Relationship between Calcination Procedure, Aluminum Configuration, and Lewis Acidity

“…Subsequently, the materials were washed once with a 0.025 M Na 2 H 2 EDTA solution at room temperature to remove possible debris formed during cooling of the synthesis mixture. Dealumination of the external surface by this treatment is unlikely, as we reported recently (22). X-ray powder diffraction confirmed that with both syntheses zeolite Beta was obtained.…”

Probing the Lewis Acidity and Catalytic Activity of the Metal–Organic Framework [Cu3(btc)2] (BTC=Benzene‐1,3,5‐tricarboxylate)

“…The selectivity to 2 is usually not higher than 55 % with Brønsted acids, while with Lewis acids selectivities as high as 85 % can be reached. [21,23,24] As 1 is highly reactive, reactions were performed at room temperature. As only compound 2 is of interest, yields of other products are not reported here.…”

“…Particularly for the isomerization of 1 this is not surprising, since 1 is a very reactive and rather large molecule. [24,35] However, by using regeneration procedures with ethanol and water as solvents, catalytic activities could be brought back close to their original values.…”

Atom efficiency and catalysis in organic synthesis

“…Lewis acids such as ZnCl 2 are generally used, often in stoichiometric amounts, to perform such transformations. According to recent reports [14][15][16], zeolites can be used as recyclable solid acid catalysts for these reactions. Two commercially relevant examples are shown in Fig.…”

“…3) is of considerable commercial importance as the product is the precursor of the sandalwood fragrance, santalol. Solid acid catalysts for this reaction include modified H-USY zeolite [15] and Ti-beta zeolite (Al-free) [16]. With the latter selectivities up to 89% in the liquid phase and 94% in the vapor phase were obtained, exceeding the best yields obtained with homogeneous Lewis acids.…”