Non-Classical Transformation of Benzendiazonium Hydrogen Sulfates. Access to 1,3-Dimethylisochromeno[4,3-c]pyrazol-5(1H)-one, a Potential Benzodiazepine Receptor Ligand
作者:Benedetta Maggio、Demetrio Raffa、Maria Raimondi、Giuseppe Daidone
DOI:10.3390/molecules181013096
日期:——
The compound 2-((1,3-dimethyl-1H-pyrazol-5-yl)(methyl)carbamoyl)benzene-diazonium hydrogen sulfate (10) was reacted with copper sulfate and sodium chloride, in the presence of ascorbic acid as reducing agent, to afford a mixture of the chlorinated epimers 4'-chloro-2,2',5'-trimethyl-2',4'-dihydrospiro[isoindoline-1,3'-pyrazol]-3-one (18) and (19), the epimers 4'-hydroxy-2,2',5'-trimethyl-2',4'-dih
化合物2-((1,3-二甲基-1H-吡唑-5-基)(甲基)氨基甲酰基)苯-重氮硫酸氢盐(10)在抗坏血酸作为还原剂存在下与硫酸铜和氯化钠反应试剂,以提供氯化差向异构体 4'-氯-2,2',5'-三甲基-2',4'-二氢螺[异二氢吲哚-1,3'-吡唑]-3-酮 (18) 和(19)、差向异构体 4'-羟基-2,2',5'-三甲基-2',4'-二氢螺[isoindoline-1,3'-吡唑]-3-one (20) 和 (21),和 N-(1,3-二甲基-1H-吡唑-5-基)苯甲酰胺 (22)。在上述条件下,重氮盐 10 既不能提供 2-氯-N-(1,3-二甲基-1H-吡唑-5-基)-N-甲基苯甲酰胺 (23) 也不能提供三环衍生物 24,这是分别是 Sandmeyer 和 Pschorr 反应。最后,通过在 210 °C 下加热 20,化合物 1,获得3-二甲基异色烯[4,3-c]吡唑-5(1