加巴喷丁-内酰胺和柠檬酸形成玻璃状疏水性低共熔混合物。两种组分的某些非共晶摩尔比也是低熔点混合物,并且在它们的微分量热曲线中可以看出细微的差异。然而,它们对丙二腈、芳醛和双甲酮的反应施加不同的选择性促进。有趣的是,反应混合物选择性地产生四氢苯并[ b ]吡喃-2H-酮或1,8-二氧代-八氢呫吨,取决于在加巴喷丁-内酰胺/柠檬酸的熔化的2/1或1/2摩尔混合物中进行。对于1/1摩尔比的加巴喷丁-内酰胺和柠檬酸混合物的熔化也观察到优异的促进活性。该熔体被证明是通过芳基醛、苯胺衍生物、水和乙炔酯的多米诺反应合成4-羟基-2,5-二氢吡咯-5-酮的有效促进剂。不需要额外的有机溶剂来进行反应,并且生物相容性熔体在与产品轻松分离后可以重复使用多次。即使在环境温度下长期储存,共晶和非共晶熔体仍保持其粘性液态。
Abstract A series of substituted 4H-pyrans derivatives were synthesized by a one-pot, multi-component reaction of aromatic aldehydes, malononitrile, and pyrazolone derivatives or active methylene carbonyl compounds such as dimedone, in the presence of 1,3-dimethyl imidazolium dimethyl phosphate [DMImd-DMP] as a catalyst in aqueous ethanol. Recyclability of the catalyst, high yields, simple product
the optimal conditions for the preparation of 2-amino-4H-benzo[b] pyrans catalyzed by p-toluenesulfonate pyridinium are in refluxed water and with 10 mol% of catalyst. Given these results and to show the generality of the procedure, we applied the optimized reaction conditions for the synthesis of various 2-amino-4H-benzo[b] pyrans from a range of substituted aromatic and heteroaromatic aldehydes. The
Non-catalytic solvent-free synthesis of 5,6,7,8-tetrahydro-4H-chromenes from aldehydes, dimedone and malononitrlie at ambient temperature
作者:Michail N. Elinson、Fedor V. Ryzhkov、Tatiana A. Zaimovskaya、Mikhail P. Egorov
DOI:10.1016/j.mencom.2015.05.008
日期:2015.5
Non-catalytic solvent-free assembling of aldehydes, dimedone and malononitrile at ambient temperature affords substituted 5,6,7,8-tetrahydro-4H-chromenes in 88-98% yields.