The Knoevenagel condensation of aromatic aldehydes with active methylene compounds such as malononitrile, ethyl cyanoacetate, benzimidazole-2-acetonitrile and benzothiazole-2-acetonitrile proceeded very smoothly, in a reusable and cheap choline chloride and urea based deep eutectic solvents. Both reaction time and yield are satisfactory. The advantages of this catalyst are that it is readily available
Nano-Fe<sub>3</sub>O<sub>4</sub>Encapsulated-Silica Particles Bearing 3-Aminopropyl Group as a Magnetically Separable Catalyst for Efficient Knoevenagel Condensation of Aromatic Aldehydes with Active Methylene Compounds
Knoevenagel condensation of aromaticaldehydes with active methylene compounds such as malononitrile, ethylcyanoacetate, benzimidazol‐2‐acetonitrile and benzothiazole‐2‐acetonitrile proceeded very smoothly, catalyzed by nano‐Fe3O4 encapsulated‐silica particles supported primary amine. Both reaction time and yield are satisfying. The advantages of this catalyst are ease of preparation, non‐toxicity
纳米Fe 3 O 4包封的二氧化硅颗粒负载的伯胺催化了芳香醛与丙二醛,丙二酸咪唑-2-乙腈和苯并噻唑-2-乙腈等活性亚甲基化合物的Knoevenagel缩合反应。反应时间和产率都令人满意。该催化剂的优点是易于制备,无毒,成本低,易于处理和可回收利用。
A facile access to novel spiroxindole fused pyrrolidine and thiazolo pyrrolidine benzimidazole derivatives via 1,3-dipolar cycloaddition reaction
作者:Nataraj Poomathi、Sivakali Mayakrishnan、D. Muralidharan、Paramasivan T. Perumal
DOI:10.1016/j.tetlet.2014.12.088
日期:2015.1
2-c]thiazole] carbonitrile were synthesized via 1,3-dipolarcycloaddition (1,3-DC) reaction. The azomethine ylides generated in situ from isatin/N-substituted isatin and secondary amino acids (sarcosine/S-proline) reacted with benzo-imidazol-2-yl-3-phenylacrylonitrile as a dipolarophile to give spiroxindole fused pyrrolidine and thiazolo pyrrolidine benzimidazole derivatives in good yields. The structure and stereochemistry
一系列苯并[ d ]咪唑-2-基)-1'-甲基-2-氧代-4'-苯基螺[吲哚啉-3,2'-吡咯烷]和苯并[ d ]咪唑-2-基)-2氧代基-7'-苯基-3',6',7',7a'四氢-1' ħ -螺[二氢吲哚-3,5'-吡咯并[1,2- c ^ ]噻唑]腈分别经由1中合成,3-偶极环加成(1,3-DC)反应。由Isatin / N-取代的isatin和仲氨基酸(sarcosine / S-脯氨酸)原位生成的偶氮甲基化物与苯并咪唑-2-基-3-苯基丙烯腈作为双极性亲和剂反应生成螺并吲哚稠合的吡咯烷和噻唑并吡咯烷苯并咪唑衍生物丰产。1 H和13证实了环加合物的结构和立体化学C NMR光谱,质谱和单晶X射线衍射研究。