Premium
The synthesis and chemical reactivity of thieno[2,3‐ c ]‐ and thieno[3,2‐ c ] pyridines
Author(s) -
Dressler Mitchell L.,
Joullié Madeleine M.
Publication year - 1970
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.5570070605
Subject(s) - chemistry , electrophile , formylation , reactivity (psychology) , nucleophile , pyridine , medicinal chemistry , dissociation (chemistry) , stereochemistry , computational chemistry , organic chemistry , catalysis , medicine , alternative medicine , pathology
The syntheses and reactions of various thieno[2,3‐ c ]‐ and thieno[3,2‐ c ] pyridines are described. Molecular orbital calculations were performed on thieno[2,3‐ c ]pyridine (1) in order to determine the most susceptible sites to electrophilic and nucleophilic attack. Superdelocalizability values, S r ‐ are reported for each position in this molecule to give relative orders of reactivity towards the two types of reactions. Electrophilic attack was found to occur experimentally at C‐3 in all the thienopyridines studied. Peracid oxidation of thieno[2,3‐ c ]‐ and thieno[3,2‐ c ]pyridines produced only the N ‐oxide. The lack of reactivity of certain thienopyridines under Vilsmeier formylation and Friedel‐Crafts acetylation conditions was related to their basicities. The dissociation constants of various thienopyridinium salts are reported.