Synthesis of Dispiro 1,3-Oxazepine4,7-Diones

Abstract

Dispiro-1,3-oxazepine-4,7-diones can be synthesized by reaction of
thiosemicarbazide with carbon disulphide in alcoholic anhydrous sodium
carbonate gives 2-amino-5-mercapto-1,3,4-thiadiazole (I). Compound (II) were
synthesized by the reaction of compound (I) with methyl iodide, this product has
been oxidized to sulphone derivatives. The Schiff's bases of the
compounds(IVa,IVb) were synthesized by condensation of different aromatic
aldehydes with sulphone derivatives, the Schiff' bases were cyclized with
pyromelitic dianhydride to give dispiro-1,3-oxazepine -4,7-diones as shown in
scheme[1]. The new compounds were characterized by physical properties and
spectral data (FT-IR).