乙腈与吡咯苯胺构筑喹喔啉的[5+1]环化反应OA

A[5+1]cyclization reaction involving acetonitrile was developed to synthesize quinoxaline derivatives.Using pyrrolidine as substrate and acetonitrile as both solvent and reagent,the[5+1]cyclization of pyrrolidine[1,2-a]quinoxaline molecules was achieved without additional metal catalyst.After a series of screening conditions,the optimal reaction conditions were as follows:p-methylbenzenesulfonic acid monohydrate(3 eq)as catalyst,H2O(5 eq),acetonitrile as solvent(0.5 mL),reaction at 140℃for 14 hours,the highest yield of 85%.In addition to pyrrolidine,a series of different guiding groups are successfully compatible,and the reaction can be applied to a wide range of substrates.