• 文献标题:   Graphene Oxide: A Metal- Free Carbocatalyst for the Synthesis of Diverse Amides under Solvent- Free Conditions
  • 文献类型:   Article
  • 作  者:   PATEL KP, GAYAKWAD EM, PATIL VV, SHANKARLING GS
  • 作者关键词:   carbocatalyst, graphene oxide, metalfree condition, transamidation, recyclability
  • 出版物名称:   ADVANCED SYNTHESIS CATALYSIS
  • ISSN:   1615-4150 EI 1615-4169
  • 通讯作者地址:   Inst Chem Technol
  • 被引频次:   8
  • DOI:   10.1002/adsc.201801673
  • 出版年:   2019

▎ 摘  要

An environmentally friendly, inexpensive, carbocatalyst, graphene oxide (GO) promoted efficient, metal-free transamidation of various carboxamides with aliphatic, cyclic, and aromatic amines is demonstrated. The protocol is equally applicable to phthalimide, urea, and thioamide determining its adaptability. The oxygenated functionalities such as carbonyl (C=O), epoxy (O), carboxyl (COOH) and hydroxyl (OH), present on graphene oxide surface impart acidic properties to the catalyst. The graphene oxide being heterogeneous in nature, work efficiently under solvent-free reaction conditions providing desired products in good to excellent yields. The one-pot synthesis of 2,3-Dihydro-5H-benzo[b]-1,4-thiazepin-4-one moiety by GO catalyzed Aza Michael addition followed by intramolecular transamidation is also described. A plausible reaction mechanistic pathway involving H-bonding is discussed. The graphene oxide can be recycled and reused up to five cycles without much loss in catalytic activity.