학술논문
Synthesis of 5‐oxo‐5H‐chromeno[3,4‐c]pyridine‐1‐carbonitriles and features of their NMR spectra.
Document Type
Article
Author
Source
Subject
*PROTONS
Language
ISSN
0022-152X
Abstract
Two different methods leading to 5‐oxo‐5H‐chromeno[3,4‐c]pyridine‐1‐carbonitriles were investigated. Reactions of 3‐aminocrotonirile with substituted salicylaldehydes provided 5‐oxo‐5H‐chromeno[3,4‐c]pyridine‐1‐carbonitriles with the same substituent on positions 2 and 4 of the system. The reaction of 3‐aminocrotonirile with variety of substituted 3‐acetylcoumarins lead to 5‐oxo‐5H‐chromeno[3,4‐c]pyridine‐1‐carbonitriles with different substituents on positions 2 and 4. The structures of the products were confirmed by spectroscopic methods. The presence of nitrile moiety in the structures with fixed geometry caused the highly downfield shift of the aromatic proton at position 10 in 1H NMR spectrum. The electronic factor of the substituents caused variation of this downfield shift. [ABSTRACT FROM AUTHOR]