Hypervalent iodine in synthesis 93. A facile synthesis of 2-substituted imidazo[1,2-a]pyrimidines by cyclocondensation of alkynyl(phenyl)iodonium salts and 2-aminopyrimidine

摘要

Simple stirring of a mixture of the alkynyl(phenyl)iodonium salts I with 2- aminopyrimidine 2 in chloroform under reflux for two hours in the presence of K2CO3 gave, after workup, the 2-substituted imidazo[1,2-a]pyrimidines 3 in moderate to good yields. A possible mechanism for the formation of 3 involves the intramolecular cyclization of the intermediate alkylidenecarbene 6. [References: 27]