Aromatic aldehydes are smoothly converted into the corresponding acylals in good yields in the presence of 3–10 mol% Bi(NO3)3•5H2O. Ketones are not affected under the reaction conditions. The relatively non-toxic nature of the catalyst, its ease of handling, easy availability and low cost make this procedure especially attractive for large-scale synthesis.
Mohan, Ram; Aggen, David; Arnold, Joshua; Hayes, Patrick; and Smoter, Nathaniel, "Bismuth Compounds in Organic Synthesis. Bismuth Nitrate Catalyzed Chemoselective Synthesis of Acylals from Aromatic Aldehydes" (2004). Scholarship. 1.