一种通用的、面向底物的多组分反应,用于合成新型高度非对映选择性四氢-1′H-螺[吡唑并[4,3- f ]喹啉-8,5′-嘧啶]-2′,4′,6′(3 ' H )-三酮(dr 高达 20 : 1(顺式:反式))和四氢-8 H -吡唑并[4,3- f ]嘧啶并[4,5- b ]喹啉-8,10(9 H )-证明了在相同的反应条件下(即乙醇作为反应介质和低共熔混合物作为催化剂)通过选择性形成多个C-C键来合成二酮。这两种方法都涉及温和的反应条件,使用无害溶剂,并有助于目标化合物获得良好至优异的反应产率。
A series of new pyrazolo[3,4-f]quinoline derivatives were synthesized by multicomponent reactions of equimolar amounts of aromatic aldehydes 1, barbituric acids 2 (barbituric acid or 1,3-dimethyl barbituric acid), and 5-aminoindazole 3 in mixed solvent of glacial acetic acid and ethylene glycol (2:1, v/v) without catalyst under microwave irradiation. This one-pot protocol has the advantage of good yields (91-94%), simple workup procedure, and short reaction times (5-6 min).