1610411-18-1Relevant articles and documents
Domino reaction of arylglyoxals with pyrazol-5-amines: Selective access to pyrazolo-fused 1,7-naphthyridines, 1,3-diazocanes, and pyrroles
Jiang, Bo,Fan, Wei,Sun, Mu-Yan,Ye, Qin,Wang, Shu-Liang,Tu, Shu-Jiang,Li, Guigen
, p. 5258 - 5268 (2014/06/23)
New multicomponent domino reactions of arylglyoxals with pyrazol-5-amines have been established, providing selective access to unprecedented pyrazolo-fused 1,7-naphthyridines, 1,3-diazocanes, and pyrroles (up to 52 examples). The unreported dipyrazolo-fused 1,7-naphthyridines were regioselectively synthesized through a special double [3 + 2 + 1] heteroannulation accompanied by direct C-C formation between two electrophilic sites of arylglyoxals. The unusual [3 + 3 + 1 + 1] cyclization resulted in 20 examples of novel dipyrazolo-fused 1,3-diazocanes, whereas pyrrolo[2,3-c] pyrazoles were obtained in good yields by varying arylglyoxals 1 and pyrazol-5-amines 2 in the ratio 1:2. Mechanisms of formation of these three new types of heterocycles are also proposed.