One-Pot Synthesis of Some New α-Bromoketals and Acetals via ۱,۸-Diazabicyclo[۵.۴.۰] Undec-۷-ene-Hydrobromide-Perbromide

α-Bromoketals and acetals are important synthetic precursors in organic synthesis. In this work, some new α-bromoketals are synthesized by the reaction of aryl methyl ketones with diols in the presence of ۱,۸-diazabicyclo[۵.۴.۰] undec-۷-ene (DBU) hydrobromide-perbromide in good isolated yields. The latter compound converts aldehydes to acetals and serves as a new and efficient reagent for the synthesis of acetals. Comparative studies of the preparation of  α-bromoketal and acetals using some reported methods versus the present method show that DBUH-Br۳ is one of the most efficient reagents for the preparation of these compounds. Conversion of carbonyl compounds to corresponding α-bromoketals and acetals in the presence of DBUH-Br۳ under microwave irradiation is also described.

کلیدواژه ها:

۱ ، ۸-Diazabicyclo[۵.۴.۰] undec-۷-ene (DBU) hydrobromide-perbromide ، Aryl methyl ketones ، α-Bromoketals ، Acetals ، Microwave irradiation