Conversion of Aryl Aldehydes to Benzyl Iodides and Diarylmethanes by H3PO3/I2

For the first time, H3PO3 was used as both the reducing reagent and the promotor in the reductive benzylation reactions with aryl aldehydes. By using a H3PO3/I-2 combination, various aromatic aldehydes underwent iodination reactions and Friedel-Crafts type reactions with arenes via benzyl iodide intermediates, readily producing benzyl iodides and diarylmethanes in good yields. Intramolecular cyclization reactions also took place, giving the corresponding cyclic compounds. This new strategy features easy-handling, low-cost, and metal-free conditions.

Automated summary

For the first time, H3PO3 was utilized as both the reducing reagent and the promotor in reductive benzylation reactions with aryl aldehydes. The combination of H3PO3/I-2 enabled various aromatic aldehydes to undergo iodination reactions and Friedel-Crafts type reactions with arenes, easily producing benzyl iodides and diarylmethanes in good yields while also leading to intramolecular cyclization reactions to give corresponding cyclic compounds. This novel strategy offers advantages of easy-handling, low-cost, and metal-free conditions.