The System Of I2/morpholine For Researching The Iodine's Site On Imidazo[1,2-a]pyridine

Imidazo[1,2-a]pyridine which with antiviral,antibacterial,antimicrobial activity and it can resistance to fatigue,anxiety.It can treat cancer,high blood preSure,ulcer and psychosis.Therefore imidazo[1,2-a]pyridine has wide application in the field of medicine.Because of imidazo[1,2-a]pyridine's chemical property is not vivacious,and no substituent of imidazo[1,2-a]pyridine is hardly reacte with others.However becoming iodo-imidazo[1,2-a]pyridine can solve the above problems.Because of the iodine ion has weak electronegativity,the chemical bond of C-I is weakened,and the chemical-bond energy is low.So the target compounds can react with alkynes,olefins,organometallic reagents,and boric acid compounds in mild conditions.The research of iodo-imidazo[1,2-a]pyridine is leS,so makes the subject is very novel and value.The conventional way of making target compounds is using with N-Iodosuccinimide?NIS?,but the iodine's site is in three generations of this reaction.In order to enrich the structure of imidazo[1,2-a]pyridine that has different substitution sites,we study different methods of iodine reaction to get different site of iodo-imidazo[1,2-a]pyridine compounds,and make they have better application in medicine and chemical industry and other fields.We first use the system of I₂/morpholine to synthesize iodo-imidazo[1,2-a]pyridine in this paper,and this method is also produced different site of iodo-imidazo[1,2-a]pyridine compounds compares with NIS.The most important thing is that the method's operating is mild and simple,so it suitable for industrial production.In this paper,we use different functional groups of 2-aminopyridine and bromoacetaldehyde diethyl acetal as raw material to synthesize imidazo[1,2-a]pyridine compounds,and then we separately use NIS and I₂/morpholine system to synthesize iodo-imidazo[1,2-a]pyridine.By comparing the structure of iodo-imidazo[1,2-a]pyridine compounds,we study the sites of iodine.We select 12 different imidazo[1,2-a]pyridine compounds for mother ring,then react with NIS or the system of I₂ and morpholine.Finally,we use 1H NMR,MS and The X-ray single crystal diffraction to confirm the structure of the target compounds,summarizes iodine generation's rule and study the impact of different groups on the iodine generation site.