Performance Comparison of [ONS]‐Type and [ONO]‐Type Schiff Bases in the Acylphosphonylation of Aldehyde

Abstract Two novel [ONS]‐type tridentate Schiff base ligands were prepared and employed in the acylphosphonylation of aldehyde. Ligand L1 was derived from 2‐amino‐3‐methylbutane‐1‐thiol and 3,5‐di‐ tert ‐butyl salicylaldehyde, and L1 /Ti(O i ‐Pr) 4 exhibited moderate to good activities to produce α‐acyloxyphosphonate. Furthermore, the performance difference of L1 and the traditional [ONO]‐type tridentate Schiff base L3 coordinating with Ti IV or Al III was also investigated.