Acetals are obtained in good yields by treatment of aldehydes and ketones with trialkyl orthoformate and the corresponding alcohol in the presence of 0.1 mol % Bi(OTf)3.4H2O. A simple procedure for the formation of acetals of diaryl ketones has also been developed. The conversion of carbonyl compounds to the corresponding 1,3-dioxolane using ethylene glycol is also catalyzed by Bi(OTf)3.4H2O (1 mol %). Two methods, both of which avoid the use of benzene, have been developed.

A practical method for large-scale acetylation of 1° and 2° alcohols as well as diols has been developed. The acetylation proceeds smoothly in MeCN with as little as 0.1 mol% bismuth triflate in good yields.

Protection Protection O 0345A Simple and Versatile Method for the Synthesis of Acetals from Aldehydes and Ketones Using Bismuth Triflate. -Bismuth triflate is found to be a mild and versatile catalyst for the synthesis of a variety of acetals and 1,3-dioxolanes. Even acetals of diaryl ketones can be prepared in excellent yields. -(LEONARD, N. M.; OSWALD, M. C.; FREIBERG, D. A.; NATTIER, B. A.; SMITH, R. C.; MOHAN*, R. S.; J. Org.

A Simple and Practical Method for Large-Scale Acetylation of Alcohols and Diols Using Bismuth Triflate.--(CARRIGAN, MARC D.; FREIBERG, DEREK A.; SMITH, RUSSELL C.; ZERTH, HERBERT M.; MOHAN, RAM S.; Synthesis