Theoretical study on the mechanism and stereochemistry of salicylaldehyde-Al(III)-catalyzed hydrophosphonylation of benzaldehyde

► The reaction undergoes PH activation, CP bond formation and recovery of catalyst. ► The CP bond formation is rate-and stereo-determining step. ► Deprotonation of HCl is easier than deprotonation of DEHP. ► Dimeric Al active species performs higher catalytic efficiency than monomeric one. ► The stereoselectivity is controlled by repulsion between adamantanyl and phenyl ring.