Niobic acid, Nb2O5·nH2O, has been studied as a heterogeneous Lewis acid catalyst. NbO4 tetrahedra, Lewis acid sites, on Nb2O5·nH2O surface immediately form NbO4−H2O adducts in the presence of water. However, a part of the adducts can still function as effective Lewis acid sites, ...
And a pos4soibf 1le3 bMiofluecnucletsio2n01a8l, a23c,ti1v89ation mechanism was proposed as shown in Scheme 5. The Lewis acidity of Zn(C46Fof51)23 wZna(sCn6eFu5)t2rwalaizsendecuotmraplilzeetdelycoimn CplLeAte,lywihnerCeLasAi,t whaesrqeuaesnitchweadspqaurtelnycihnewd epaakrtilny...