75018-05-2Relevant academic research and scientific papers
Studies on Pyrazines. 24. A Simple and Versatile Synthetic Method for 3-Alkoxy- and 3-Aminopyrazinecarbonitriles
Sato, Nobuhiro,Matsui, Nobuo
, p. 1689 - 1692 (2007/10/02)
New and concise synthetic methods of 3-alkoxy- and 3-aminopyrazinecarbonitriles by nucleophilic displacement of 3-phenylsulfonylpyrazinecarbonitriles are reported.
Studies on Pyrazines. Part 22. Lewis Acid-Mediated Cyanation of Pyrazine N-Oxides with Trimethylsilyl Cyanide: New Route to 2-Substituted 3-Cyanopyrazines
Sato, Nobuhiro,Shimomura, Yuji,Ohwaki, Yoshie,Takeuchi, Ryo
, p. 2877 - 2882 (2007/10/02)
Reaction of 3-substituted pyrazine 1-oxides with trimethylsilyl cyanide in the presence of triethylamine in acetonitrile gave the corresponding cyanopyrazines, yields of which depended remarkably on the substituent.Electron-donating groups enhanced the cyanation with high regioselectivity to 2-substituted 3-cyanopyrazines, while a chloro substituent suppressed the conversion.Addition of zinc halide to the reaction mixture, in most cases, increased the reactivity and improved the regioselectivity.On the other hand, the N-oxides carrying an electron-withdrawing methoxycarbonyl or N-butylcarbamoyl group underwent the cyanation, without need for the Lewis acid, to provide a mixture of nearly equal amounts of 2-substituted 3- and 5-cyanopyrazines.The latter compound was exclusively obtained when 3-methoxycarbonyl- or 3-cyanopyrazine 1-oxide was treated with diethoxyphosphoryl cyanide.
Studies on Pyrazines. 18 . A New and Convenient Synthesis of 2-Amino-3-cyanopyrazine
Sato, Nobuhiro
, p. 817 - 819 (2007/10/02)
The titled compound, 2-amino-3-cyanopyrazine (1), was prepared by reaction of 3-aminopyrazine 1-oxide (7) with trimethylsilyl cyanide.Furthermore, conditions of individual steps in synthetic route to 7 starting from 2-pyrazinecarboxamide were optimized.
One-step Preparation of 3-Alkoxypyrazine-2-carbonitriles from Pyrazine-2,3-dicarbonitriles and Related Reactions
Kojima, Takakazu,Nagasaki, Fumihiko,Ohtsuka, Yozo
, p. 455 - 459 (2007/10/02)
A series of 5,6-disubstituted 3-alkoxypyrazine-2-carbonitriles (2a-i) were prepared from 5,6-disubstituted pyrazine-2,3-dicarbonitriles (1a-d) by direct substitution with alcohols.Treatment of 1 with amines gave either pyrrolopyrazines (3a,b) or substitution products (4,5).In a low temperature range, 1 afforded imidates and related compounds (6-11).The preference among these reactions depended on the 5,6-substituents and on the reaction conditions.
