Carbon dioxide: a reagent for simultaneous protection of nucleophilic centers and the activation of alternative locations to electrophilic attack. V. Activation of the 2-alkyl group of a 2-alkylindole toward proton loss and subsequent electrophilic substitution
The reaction of ethyl3-(o-trifluoroacetamidoaryl)-1-propargylic carbonates with primary or secondary amines in the presence of Pd 2 (dba) 3 , dppf, and carbon monoxide in THF at 80 °C provides ready access to free-NH indole 2-acetamides. The reaction can be applied to the synthesis of free-NH indole 2-acetic acid methyl esters.
CoFe2O4@SiO2-NH-βCD-BF3 as a supramolecular nanocomposite: Synthesis, characterization and catalytic activity
作者:Hosein Hamadi、Zohreh Zanjani、Mahtab Yadollahi
DOI:10.1016/j.poly.2019.114219
日期:2020.1
This manuscript describes synthesis of BF3-functionlized beta-cylcodextrine grafted magnetic CoFe2O4 nanaoparticles as a hybrid magnetic nano-composite (CoFe2O4@SiO2-NH-OCD-BF3). The CoFe2O4@SiO2NH-beta CD-BF3 was fabricated by grafting of 6-O-toluenesulfonyl cyclodextrin (6-Ts-beta CD) to 3-aminopropyl triethoxysilane coated magnetic CoFe2O4@SiO2 nanoparticles followed by combination with BF3. The CoFe2O4@SiO2-NH-beta CD-BF(3)was characterized by FT-IR, TGA, VSM and SEM techniques. The feasibility of using CoFe2O4@SiO2-NH-beta CD-BF3 as a magnetically recoverable catalyst was confirmed in the modified-Ritter reaction. The result showed that this novel nano-composite could serve as an efficient nanoreactor bearing super-acidic sites formed by immobilized BF3 and reuse at least for 6 times without loss in activity. (C) 2019 Elsevier Ltd. All rights reserved.
Inagaki, Satoshi; Nishizawa, Yoshihiro; Sugiura, Takashi, Journal of the Chemical Society. Perkin transactions I, 1990, # 1, p. 179 - 180