An Efficient Synthesis of 3,3′,4,4′‐Tetrahydro‐4,4′‐bibenzo[e][1,3]oxazine‐2,2′‐dione Derivatives with the Aid of Low‐valent Titanium

Synthesis of 3,3′,4,4′-tetrahydro-4,4′-bibenzo[e][1,3]oxazine-2,2′-diones via reaction of salicylidendphenylhydrazone and triphosgene with the aid of low-valent titanium reagent is described. This method has the advantages of accessible starting materials, good yields and short reaction time.