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2.6- Dimethylpyrazine 1-oxide, with acetic

Other reactions with their counterparts in the pyridine series are also well known. Thus, 2,3-dimethylpyrazine 1,4-dioxide reacts with acetic anhydride to yield 2,3-bis(acetoxy-methyl)pyrazine (S3) in good yield (72KGS1275). Pyrazine 1-oxide also reacts directly with acetic anhydride to yield 2(ljH)-pyrazinone by way of the intermediate acetate (Scheme 22). The corresponding reaction in the quinoxaline series is not so well defined and at least three products result (Scheme 23) (67YZ942). [Pg.171]

Pyrazine 1-oxide, 2-methylpyrazine 4-oxide, and 2,6-dimethyl-pyrazine 4-oxide are unreactive toward acetic anhydride, but 2,5-dimethylpyrazine 1-oxide, 2,6-dimethylpyrazine 1-oxide, and 2,3,5,6-tetramethylpyrazine 1-oxide react to give 2-acetoxymethyl derivatives. The following mechanism (Scheme 44) is consistent with the observation that an acetoxymethyl derivative is only formed when a methyl group is adjacent to the AT-oxide function.407 However, in... [Pg.196]

Dimethylpyrazine 1-oxide is converted into 2,5-dimethyl-3-propylmercaptopyrazine on treatment with 1-propanethiol and acetic anhydride, and similarly the 1,4-dioxide yields the bisthio ether (206).409... [Pg.197]

Some 2 -dialkylpyrazines have been oxidized in one step with sodium dichromate in acetic acid, in good yields, to the corresponding 2-acyl-3-alkylpyrazines (678). Thus 2-ethyl-3-methylpyrazine gave 2-acetyl-3-methylpyrazine, 23-diethylpyrazine gave 2-acetyl-3-ethylpyrazine, and 2-ethyl-3,5(or 3,6)-dimethylpyrazine gave 2-acetyl-3,5(or 3,6)-dimethylpyrazine (678). [Pg.79]

Bauer and Hirsch (764) found that 2,5-dimethylpyrazine 1-oxide refiuxed for 2 hours with propane-1-thiol in acetic anhydride gave 2,5-dimethyl-3-propylthio-pyrazine (5), and 2,5-dimethylpyrazine 1,4-dioxide similarly treated gave 2,5-dimethyl-3,6-dipropylthiopyrazine, but attempted reactions with benzenesulfonyl chloride instead of acetic anhydride (as in the pyridine series) were unsuccessful. [Pg.198]

Dimethylamino-23-dimethylpyrazine 1-oxide in boiling acetic anhydride gave 2-acetoxymethyl-3-dimethylamino-5-methylpyrazine (793) which was not isolated but saponified directly to 3-dimethylamino-2-hydroxymethyl-5-methylpyrazine (793). 2-Amino-3-cyano-5-methylpyrazine 1,4-dioxide refluxed with (a) acetic anhydride gave 3-acetamido-2-cyano-5-hydroxy-6-methylpyrazine 1-oxide (532) and (6) sodium methoxide gave 3-amino-2-cyano-5-methoxy-6-methylpyrazine 1-oxide (532). [Pg.245]

Cyanopyrazine A -oxides have been prepared from a-amino nitriles and a-hydroxyimino carbonyl compounds as summarized in Section III. 1 (528-530, 532-534, 537, 540, 542). Oxidation of 2-cyanopyrazine with perhydrol gave 3-cyanopyrazine 1-oxide (575), 2-cyano-5-ethoxy-3,6-dimethylpyrazine with 30% hydrogen peroxide in acetic acid at 55° gave 2-cyano-5-ethoxy-3,6-dimethylpyrazine iV-oxide (288), and the oxidations of 2-amino-3-cyanopyrazine 1-oxide (538) and... [Pg.308]


See other pages where 2.6- Dimethylpyrazine 1-oxide, with acetic is mentioned: [Pg.166]    [Pg.76]    [Pg.93]    [Pg.298]    [Pg.93]    [Pg.77]    [Pg.241]   


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2,5-Dimethylpyrazine 1-oxide with acetic anhydride

Acetalization-oxidation

Acetals oxidation

Acetate oxidation

Acetic oxide

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