Substituted 2-Sulfonamido-5-aminopyridines. II

Abstract

This concept of the mechanism of reaction is supported by the results in perchloric acid solution. Sherrill, et al.,b have shown that no complex is formed in cerium (IV) perchlorate. Under such conditions the observed reaction should be essentially the termolecular reaction (2). This would explain why the rate is greater in perchloric acid (Fig. 2), but reaction is still not instantaneous.

Transition Metal Halide Salts of 2-Amino-5-Substituted-Pyridines: Synthesis, Crystal Structure and Magnetic Properties of Two Polymorphs of (5-IAP)2CuCl4[5-IAP = 2-Amino-5-Iodopyridinium]

“…This method proved vastly superior to previously published techniques as it eliminated the need to remove large quantities of unreacted I 2 [12] or to separate 2-amino-3,5-diiodopyridine from the product [13]. The pyridine was then converted to the corresponding hydrochloride salt, 5-IAP chloride, by treatment with dry HCl in ether.…”

Bisannulation of 2,3‐Dichloro‐1,4‐naphthoquinone with o‐Nitrophenylacetic Acid Derivatives: A Succinct Synthesis of the ABCD Ring System of Alpkinidine

“…We expected that it would be possible to effect oxodeamination of 19 to give model target 1 by diazotization (to give 20 ), hydrolysis, and tautomerisation of the initially formed hydroxypyrrole 21 . While such reactions are commonplace with 2‐aminopyridines13 and related six‐membered heterocycles, there are only two very low‐yielding precedents for 2‐aminopyrroles 14. In practice, none of the desired product was observed upon treatment of 19 with aqueous nitrous acid, and only the deaminated pyrrole 22 was isolated in low yield.…”

Nitropyridines: X. Palladium-catalyzed cross-coupling of 2-bromo-5-nitropyridine with terminal acetylenes

“…The simplicity of replacement of 2(4)-hydroxy and 2(4)-amino groups in the corresponding 3(5)-nitropyridines by halogen determines accessibility of halonitropyridines and their possible wide application in the synthesis of ethynylpyridines via cross-coupling reaction [3][4][5][6][7][8][9]. Interest in new ethynylnitropyridines is stimulated by their potential biological activity [10][11][12].…”