Tandem Intermolecular–Intramolecular Michael Addition of Bifunctional Hetero Nucleophiles to Polyfluoro-2-alkynoic Acids. Facile Synthesis of Polyfluoroalkylated Azaheterocycles

1994 ◽  
Vol 67 (11) ◽  
pp. 3021-3029 ◽  
Author(s):  
Kazumasa Funabiki ◽  
Kazushige Tamura ◽  
Takashi Ishihara ◽  
Hiroki Yamanaka
Keyword(s):  
Michael Addition ◽  
Facile Synthesis

Facile Synthesis of 2-Arylindoles through Plancher-Type Rearrangement of 3-Alkyl-3-Arylindolenines

Synlett ◽  
2017 ◽  
Vol 28 (15) ◽  
pp. 1994-1999
Author(s):  
Santhosh Chittimalla ◽  
Chennakesavulu Bandi ◽  
Vinod Gadi ◽  
Siva Gunturu
Keyword(s):  
Michael Addition ◽  
Facile Synthesis ◽  
Type C ◽  
High Yields

3-Alkylindoles on reaction with a cyclohexa-2,4-dien-1-one catalyzed by BF3·OEt2 gave the corresponding 3-alkyl-3-arylindolenines in high yields through a tandem Michael addition/aromatization sequence. In the presence of HCl, these indolenine derivatives underwent a facile Plancher-type C-3 to C-2 aryl rearrangement to deliver the corresponding 2-arylindoles.

Facile Synthesis of Indolines by a Tandem Nitro-reduction Aza Michael Addition Reaction

Heterocycles ◽  
2013 ◽  
Vol 87 (10) ◽  
pp. 2023 ◽  
Author(s):  
Jason Guy Taylor ◽  
Wellington Martins Ventura ◽  
Luiz Guilherme Souza de Assis
Keyword(s):  
Michael Addition ◽  
Addition Reaction ◽  
Michael Addition Reaction ◽  
Facile Synthesis ◽  
Nitro Reduction

scholarly journals A novel and practical synthesis of iclaprim

2020 ◽  
Author(s):  
Weiyuan Liu ◽  
Liang Chen ◽  
Jing Pan ◽  
Ting Zhou ◽  
Kuaile Lin ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Acetic Anhydride ◽  
Michael Addition ◽  
Knoevenagel Condensation ◽  
Total Yield ◽  
Buffer System ◽  
Facile Synthesis ◽  
Practical Synthesis ◽  
First Time ◽  
Amino Protection

A novel and facile synthesis of iclaprim was reported. Started from Trimethoprim (TMP), the amino-protection and Friedel-Crafts acetylation with acetic anhydride were simultaneously completed in CH2Cl2 with SnCl4 as catalyst. The Knoevenagel condensation of 2,4-diamino-5-(2-acetyl-3-hydroxy-4,5-dimethoxybenzyl)pyrimidine with cyclopropyl carboxaldehyde followed by the intramolecular Michael addition in the buffer system (pyrrolidine and acetic acid) installed the key framework (chromanone 13). The dehydration was catalyzed by H2SO4 so that the formation of 5-cyclopropyl-2,3-dimethoxy-4,5,6,6a,7,12-hexahydronaphtho[1,8-bc]pyrimido[5,4-f]azepin-9-amine, an impurity of iclaprim reported at the first time, could be minimized. In the end, iclaprim was obtained in a total yield of 21%.

Sign in / Sign up

Export Citation Format

Share Document