Synthesis of 2-iodomethylene-2,3-dihydro-1,4-oxazepine derivatives

Dikmen, Ezel
Seven-membered heterocyclic compounds containing two heteroatoms are at least as important as one heteroatom-containing heterocycles in many applications. Oxazepine derivatives are one of such seven-membered heterocyclic compounds. Therefore, the construction of oxazepine derivatives has attracted considerable attention among researchers because of providing useful treatments for many diseases with their pharmaceutical compositions. Accordingly, our research group has aimed to synthesize seven-membered heterocyclic compounds. In this manner, we have developed a new methodology for the synthesis of iodo-substituted 1,4-oxazepine derivatives. First of all, the synthesis of alkynyl ketones was achieved and then the preparation of N-propargylic β-enaminone derivatives was performed from the reaction of alkynyl ketones and propargyl amine. The reaction of N-propargylic β-enaminones via zinc chloride and iodine has afforded iodo-substituted 1,4- oxazepine molecules. For this study, ZnCl2 was used as a Lewis acid catalyst in order to initiate electrophilic cyclization.