Renz Michael, Blasco Teresa, Corma Avelino, Fornés Vicente, Jensen Robert, Nemeth Laszlo
Instituto de Tecnología Química, UPV-CSIC Universidad Politécnica de Valencia Avenida de los Naranjos s/n, 46022 Valencia, Spain.
Chemistry. 2002 Oct 18;8(20):4708-17. doi: 10.1002/1521-3765(20021018)8:20<4708::AID-CHEM4708>3.0.CO;2-U.
Sn-Beta is used as a heterogeneous catalyst for the Baeyer-Villiger reaction with hydrogen peroxide. Cyclic ketones are transformed into the corresponding lactones, while unsaturated ketones are oxidized to the corresponding unsaturated lactones with very high chemoselectivity. The catalyst is also selective for the oxidation of aromatic aldehydes with H2O2, producing the formate ester or the corresponding hydrolyzed product, that is the alcohol. Shape-selective oxidations are observed for isomeric reactants with different molecular shapes. The catalytic Sn sites have been characterized by 119Sn MAS-NMR spectroscopy, and tetrahedral incorporation into the zeolite framework has been demonstrated. In situ IR spectroscopy and 18O labeling experiments have shown that the oxidation mechanism involves an intermediate of the Criegee type.
Sn-β用作与过氧化氢进行拜耳-维利格反应的多相催化剂。环状酮被转化为相应的内酯，而不饱和酮则以非常高的化学选择性被氧化为相应的不饱和内酯。该催化剂对于用H2O2氧化芳香醛也具有选择性，生成甲酸酯或相应的水解产物，即醇。对于具有不同分子形状的异构体反应物观察到了择形氧化。催化Sn位点已通过119Sn MAS-NMR光谱进行了表征，并且已证明其以四面体形式掺入沸石骨架中。原位红外光谱和18O标记实验表明，氧化机理涉及Criegee型中间体。
