A catalytic method for synthesis of 6-aryl-1H-pyrazolo[3,4-d]pyrimidin-4[5H]-ones by heteropolyacids: H14[NaP5W29MoO110] and H3PMo12O40

Base-catalyzed one-pot tandem reaction: an effective strategy for the synthesis of pyrazolo[3,4-d]pyrimidinone derivatives

“…The filter cake was dried and purified by crystallization from ethanol to afford pure 4. 156.5, 152.8, 148.8, 138.9, 136.5, 130.0, 129.8, 128.8, 127.4, 122.0, 106.3, 28.6, 15.7 27 6, 152.9, 142.6, 139.0, 136.5, 129.8, 128.6, 127.4, 122.0, 106.3, 21.5; ESI-MS (m/z) = 303 ([M+H] + ). 19-8.17 (m, 2H), 7.63-7.59 (m, 4H), 7.43-7.39 (m, 1H), 3.90 (s, 6H), 3.76 (s, 3H); 13 C NMR (100 MHz, DMSO-d 6 ) (δ, ppm): 158.8, 155.8, 153.3, 152.6, 141.1, 138.9, 136.6, 129.7, 127.4, 127.3, 121.9, 28 15 (m, 4H), 7.63-7.59 (m, 2H), 7.44-7.40 (m, 1H), 7.14-7.12 (m, 2H), 3.86 (s, 3H); 13 C NMR (100 MHz, DMSO-d 6 ) (δ, ppm): 162.8, 158.8, 156.1, 152.9, 139.0, 136.5, 130.5, 130.0, 127.4, 124.5, 122.0, 114.7, 106.0, 56 157.3, 156.0, 136.5, 133.4, 131.1, 129.7, 127.4, 122.2, 121.1, 113.5, 106.3, 64.7, 14.9; ESI-MS (m/z) = 333 ([M+H] + ).…”

One‐pot Synthesis of 3‐Aminoimidazo[1,2‐a]pyridines Catalyzed by Heteropolyacids

“…18 Development of methods using HPA as solid and green catalysts for fine organic synthetic processes related to fine chemicals, such as flavors, pharmaceuticals and food additives has been under attention in the last decade. 19 Due to the numerous advantages associated with this eco-friendly, green and heterogeneous catalyst, HPA and its salts have been explored as powerful, efficient and eco-friendly catalysts for organic reactions. 20 Herein we reported the synthesis of 3-aminoimidazo[1,2-a]pyridines from reaction of 2-aminoazines, aldehydes, and isonitriles using a catalytic amount of HPA (Scheme 2).…”

“…Heteropolyacids were prepared according to the literature. 19,[24][25][26] All products are known compounds and were characterized by mp, IR, 1 H NMR and GC/MS. Melting points were measured by using the capillary tube method with an electrothermal 9200 apparatus.…”

Regioselective Synthesis of 2-Substituted [1,2,4]Triazolo[5,1-b][1,3]thiazin-7-ones by Heteropolyacids

“…HPAs have been used as industrial catalysts for several liquid-phase reactions 7-10 such as alcohol dehydration, 11 alkylation, 12 and esterification. 13 Therefore, in continuing our work using HPA [14][15][16][17] to synthesize heterocyclic systems, we investigated the use of this catalyst for the synthesis of some triazolothiazines. Here we report a rapid and ecologically safe method for the synthesis of triazolothiazines 3.…”