Science and Mathematics Faculty Publications
Covalent Amination. Substituent Effects on the Site of Addition of Ammonia to Quaternized Pyridines and Pyrazines
Document Type
Article
Publication Date
1976
Journal Title
Journal of Organic Chemistry
Volume
41
Issue
8
First Page
1303
Last Page
1308
Abstract
1,3-Disubstituted pyridinium ions react completely at about -40 "C with ammonia to give covalent amination products. Addition occurs at C-6 when the C-3 group is CONH2, C02CH3, CF3, or COCH3. Addition at C-2 results when the 3 substituent is C1 or I, and a mixture is found for the 3-CN compound. Parent 1-methyl- and l-benzylpyridinium ions do not yield 2 adducts unless powdered KOH is added to neutralize ammonium ion. 1-Methoxypyridinium ions at -50 "C give adducts which open to 5-amino-2(cis),4(trans)-pentadienalo xime 0-methyl ether. 1-Methyl-3-substituted pyrazinium ions react at the 2 position when the substituent is C1 or CH30 and at the 6 position in the CONHz case. 1-Methylpyrazinium ion first forms a 2 adduct and then a 2,3 diadduct.
Keywords
Amination, pyridines, pyrazines
Recommended Citation
Helmick, L. S. (1976). Covalent Amination: Substitution Effects on the Site of Addition of Ammonia to Quaternized Pyridines and Pyrazines. Journal of Organic Chemistry, 41, 1303-1308.