In Situ FTIR Study and Scale-Up of An Enolization−Azidation Sequence

A key step in the synthesis of an optically active aminoalcohol-containing active pharmaceutical ingredient (API) involved the diastereoselective introduction of an azido functional group on a functionalized chiral oxazolidinone. This was accomplished via a low-temperature enolization, followed by a quench with triisopropylbenzenesulfonyl azide. To enable scale-up of this process, the enolization temperature had to be increased from the original