Science and Mathematics Faculty Publications

Title

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

Share

COinS