三氟甲磺酸铜催化新型苯并恶唑烷衍生物的合成

Copper( Ⅱ) Trifluomethanesulfonate-catalyzed Synthesis of Novel Benzoxazolidine Derivatives

以三氟甲磺酸铜[Cu(OTf)_2]为催化剂,取代邻氨基苯酚(1a^1g)和取代联苯甲酰(2a^2g)为原料,合成了7个苯并恶唑烷衍生物(3a^3g,其中3b^3g为新化合物),其结构经~1H NMR,^(13)C NMR,IR和HR-MS(ESI)表征。以3a的合成为例,研究了催化剂、溶剂、催化剂用量、物料比γ[n(1)∶n(2)]和反应温度对3产率的影响。结果表明:在最佳反应条件[8 mmol%Cu(OTf)_2,1,2-二氯乙烷为溶剂,1a^1g 1.5 mmol,γ=3∶1,于70℃反应10 h]下,3a^3g产率62%~91%。

Seven benzoxazolidine derivatives(3a^3g),among them3b^3g were novel compounds,were synthesized with the substrates of substituted o-aminophenols(1a^1g)and substituted1,2-diphenylethane-1,2-dione(2a^2g),using copper(II)trifluoromethanesulfonate as catalyst.The structures were characterized by1H NMR,13C NMR,IR and HR-MS(ESI).The effects of catalyst,solvent,catalyst dosage,mole ratio{γ[n(1)∶n(2)]}and reaction temperature on yield of3were investigated using synthesis of3a as the template reaction.The results showed that under the optimum reaction conditions[8mmol%Cu(OTf)2,1,2-dichloroethane as solvent,1a^1g1.5mmol,γ=3∶1,reaction at70℃for10h],the yield of3a^3g were62%~91%.