Studies relating to heterocyclic ring formation (1964)
AuthorsDeady, L. W.show all
1,3-Diphenoxypropane has been prepared and its decomposition under various acid conditions has been studied. By refluxing with aluminium chloride in benzene, a good yield of chroman has been obtained. These optimum conditions have been applied to the decomposition of other 1,3-diphenoxypropanes and it has been found that good yields of substituted chromans are obtained from diethers containing electron donating or weakly electron withdrawing substituents which do not react with the catalyst. From the decomposition of related compounds under the same conditions, it has been shown that such a cyclisation reaction is limited to a propyl alkyl chain. 3-Anilinopropyl phenyl ether has been prepared and decomposed to give some N-phenylazetidine, rather than the expected 1,2,3,4-tetrahysroquinoline, under the standard decomposition conditions. The possible reaction paths for the chroman forming reaction are discussed and an investigation of the relative rates of decomposition of some 1,3-diphenoxypropanes has led to confirmation of a predicted synchronous mechanism.