Fused Dihydropyrimidines by a Tandem Aza-Wittig-Heterocumulene-Mediated Annulation Reaction: Synthesis of 4,5-Dihydropyrazolo[3,4-<i>d</i>]pyrimidine Derivatives
作者:Pedro Molina、Antonio Arques、María Victoria Vinader
DOI:10.1055/s-1990-26907
日期:——
4-Aminomethyl-3-methyl-1-phenyl-5-[(triphenylphosphoranylidene)amino] -1H-pyrazoles 2 (iminophosphoranes), prepared from 4-aminomethylene-3-methyl-1-phenyl-5-[(triphenylphosphoranylidene)amino] -1H-pyrazoles 1, react with aliphatic and aromatic isocyanates in refluxing toluene to give the corresponding 5-substituted 6-alkyl(aryl)amino-3-methyl-1-phenyl-4,5-dihydro-1H-pyrazolo[3, 4-d]pyrimidines 4. Iminophosphoranes 2c and 2d also react with carbon dioxide and carbon disulfide to give 6-oxo- and 6-thioxo-4,5,6,7-tetrahydropyrazolo[3,4-d]pyrimidines 5 and 6 respectively. 4-(N-4-Methylphenyl)aminomethyl-3-methyl-1-phenyl -5-[(triphenylphosphoranylidene)amino]-1H-pyrazole (2d) reacts with acyl chlorides to give 4-[N-acyl(N-4-methylphenyl)amino]methyl-3-methyl -1-phenyl-5-[(triphenylphosphoranylidene)amino]-1H-pyrazoles 7, which by thermal treatment proved resistant to cyclization to give fused pyrimidines.
4- 氨基甲基-3-甲基-1-苯基-5-[(三苯基膦亚基)氨基]-1H-吡唑 2(亚氨基磷烷),由 4- 氨基甲基-3-甲基-1-苯基-5-[(三苯基膦亚基)氨基]-1H-吡唑 1 制备、在回流甲苯中与脂肪族和芳香族异氰酸酯反应,得到相应的 5-取代 6-烷基(芳基)氨基-3-甲基-1-苯基-4,5-二氢-1H-吡唑并[3,4-d]嘧啶 4。氨基磷烷 2c 和 2d 还能与二氧化碳和二硫化碳反应,分别生成 6-氧代和 6-硫代-4,5,6,7-四氢吡唑并[3,4-d]嘧啶 5 和 6。4-(N-4-甲基苯基)氨基甲基-3-甲基-1-苯基-5-[(三苯基膦亚基)氨基]-1H-吡唑 (2d) 与酰基氯反应生成 4-[N-酰基(N-4-甲基苯基)氨基]甲基-3-甲基-1-苯基-5-[(三苯基膦亚基)氨基]-1H-吡唑 7。