[2 + 3] Annulative Coupling of Tetrahydroisoquinolines with Aryliodonio diazo compounds To Access 1,2,4-Triazolo[3,4‑a]isoquinolines

Base promoted one-pot annulative coupling of 1,2,3,4-tetrahydro­isoquinolines (THIQs) with hypervalent iodine­(III) species aryliodonio diazo compounds has been devised for the direct construction of 1,2,4-triazolo­[3,4-a]­isoquinoline derivatives at room temperature in open air for the first time. This approach involves [2 + 3] cascade annulation of nucleophilic THIQ with an electrophilic aryliodonio diazo compound via N–H and α-C1­(sp3)–H difunctionalization of THIQ.本研究首次报道了碱促进的1,2,3,4-四氢异喹啉（1,2,3,4-Tetrahydroisoquinolines, THIQs）与高价碘(III)试剂芳碘鎓重氮化合物的一锅法环化偶联策略，可在室温、敞口空气条件下直接构建1,2,4-三唑并[3,4-a]异喹啉衍生物。该方法通过对THIQ进行N-H与α-C1(sp3)-H双官能团化，实现亲核性THIQ与亲电型芳碘鎓重氮化合物的[2+3]级联环化过程。