Synthesis of Acetals from Phenylpropiolaldehydes

Acetals are important intermediates in synthetic chemistry. A series of novel alkynyl-containing acetals were synthesized from aromatic alkynyl aldehydes with AgBF4 as catalyst. All the generated products have been identified and characterized by means of melting point, IR, 1H NMR, 13C NMR, and MS analyses. The reaction conditions including suitable catalyst, temperature and reaction time were examined. A variety of substrates were tested under the optimized conditions. The tested results showed that substrates with electron-donating groups or electron-withdrawing groups are compatible in the standard conditions. The possible reaction mechanisms were proposed.