In the Arndt-Eistert synthesis (homologation of acids), what highly reactive intermediate is formed — Aldehydes Ketones and Carboxylic Acids Chemistry Question

💡 Solution & Explanation

Treatment of the diazoketone ($R-CO-CHN_2$) with $Ag_2O$ triggers the loss of $N_2$ and migration of the R-group to form a highly reactive Ketene intermediate ($R-CH=C=O$), which is then hydrated.