Synthesis and characterization of derived imines from 4-imino-5,6,7,8-tetrahydro-1-benzothieno[2,3-d]pyrimidin-3(4H)-amine

The synthesis and characterization of derived imines from 4-imino-5,6,7,8-tetrahydro-1-benzo thieno[2,3-d]pyrimidin-3(4H)-amine 3 has been developed in 3 steps through the reaction of heteroaromatic o-aminonitrile 1 with triethyl orthoformate afforded the corresponding imido ester 2 followed by cyclization with hydrazine hydrate to furnish iminothienopyrimidineamine 3 and finally the imination of 3 at room temperature with aromatic aldehydes was generated the corresponding imines (5a-5h). The new products were obtained in high yield with an easy work-up in simple reaction along with the purification of products by non-chromatographic method. This general synthetic procedure can be extended to the preparation of wide variety of imines using o-aminonitrile bifunctional derivatives which synthesized by Gewald reaction.