Nanocage-confined catalyst, preparation process and use thereof

A nanocage-confined catalyst, having an active center of formula (I-1) and/or an active center of formula (I-2):

• M(Salen1)X (1-1),
• M′(Salen2) (I-2),
• such that the catalyst has formula (I):
• NC-m[M(Salen1)X]-n[M′(Salen2)] (I),
• wherein:
• NC is a material having a nanocage structure and is selected from mesoporous silica nanoparticles having a nanocage structure or organic hybrid mesoporous silica nanoparticles having a nanocage structure,
• each occurrence of M is independently selected from the group consisting of Co ion, Fe ion, Ga ion, Al ion, Crion, and a mixture thereof;
• and each occurrence of M′ is independently selected from Cu ion, Ni ion and a mixture thereof;
• m is an integer of 0 to 10, n is an integer of 0 to 5;
• provided that at least one of m and n is not 0;
• each occurrence of Salen1 and Salen2 is independently a derivative of a Shiff base, wherein the derivative of Schiff base is N,N′-disalicylidene-1,2-cyclohexanediamine or a substituted N,N′-disalicylidene-1,2-cyclohexanediamine;
• X is an axial anion, wherein each occurrence of X is independently selected from the group consisting of unsubstituted acetate, unsubstituted benzenesulfonate, unsubstituted benzoate, F−, Cl−, Br−, I−, SbF6−, PF6−, BF4− and a mixture thereof;
• with provisos that:
• when X is unsubstituted acetate, unsubstituted benzenesulfonate, or unsubstituted benzoate, then M is not a Co ion, and when X is F−, Cl−, Br−, or I−, then m is not less than 2, and at least one occurrence of X in formula (I-1) is SbF6−.