Premium
Ring Opening and Recyclization Reactions of 3‐Nitrochromone with Some Nucleophilic Reagents
Author(s) -
Ibrahim Magdy A.,
Alnamer Youssef A.
Publication year - 2019
Publication title -
journal of heterocyclic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.321
H-Index - 59
eISSN - 1943-5193
pISSN - 0022-152X
DOI - 10.1002/jhet.3620
Subject(s) - chemistry , malononitrile , nucleophile , pyridine , reagent , cyanoacetamide , ring (chemistry) , medicinal chemistry , benzimidazole , reactivity (psychology) , thiazole , organic chemistry , catalysis , medicine , alternative medicine , pathology
The chemical reactivity of 3‐nitrochromone ( 1 ) was studied towards some nucleophilic reagents. Reaction of 3‐nitrochromone ( 1 ) with some carbon nucleophiles revealed existence of ring‐opening ring‐closure reactions, and the mode of cyclization depends on the nucleophile used. Treatment of 3‐nitrochromone ( 1 ) with malononitrile and ethyl cyanoacetate produced benzoxocinone derivatives 2 and 3 , respectively. Boiling compound 1 with cyanoacetamide and 2‐aminoprop‐1‐ene‐1,1,3‐tricarbonitrile afforded pyridine derivatives 4 and 5 , respectively. Reaction of compound 1 with 1 H ‐benzimidazol‐2‐ylacetonitrile, 5‐amino‐2,4‐dihydro‐3 H ‐pyrazol‐3‐one, and dimedone led to pyrido[1,2‐ a ]benzimidazole 6 , pyrazolo[3,4‐ b ]pyridine 7 , and chromenone 8 , respectively. Treating 3‐nitrochromone ( 1 ) with heterocyclic amines gave enaminones 11 and 12 via nucleophilic attack at C‐2 position with ring opening. The structures of the newly synthesized products were deduced on the basis of their analytical and spectral data.