Bodroux–Chichibabin aldehyde synthesis
The Bodroux–Chichibabin aldehyde synthesis is a chemical reaction whereby a Grignard reagent is converted to an aldehyde one carbon longer. Reaction of a Grignard reagent with triethyl orthoformate gives an acetal, which can be hydrolyzed to an aldehyde.
Source: Wikipedia — Bodroux–Chichibabin aldehyde synthesis (CC BY-SA 4.0)