Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

2-Methyl-5,6-pyrazinedicarboxylic acid

Methyl-5,6-pyrazinedicarboxylic acid may be prepared in 70-75% yields from 2-methylquinoxaline by this same procedure. The crude acid (m.p. 155-160°, dec.) is somewhat unstable at elevated temperatures. It should not be heated above 100° for long periods of time. In order to obtain pure 2-methyl-5,6-pyrazinedicarboxylic acid (m.p. 175°, dec.) the crude product is best recrystaUized from acetone. [Pg.105]

Quinoxaline has been prepared by the reaction of glyoxal with o-phenylenediamine, and 2-methylquinoxaline by the reaction of pyruvic aldehyde or isonitrosoacetone with < -phenylenedi-amine. 2,3-Pyrazinedicarboxylic acid has been prepared only by the permanganate oxidation of quinoxaline. 2-Methyl-5,6-pyrazinedicarboxylic acid has been prepared from 2-methyl-quinoxaline in the same way. - ... [Pg.105]

Methyl-l-iodopropane, 31, 32 2-Methyl-2-iodopropane, 31, 32 Methylmagnesium bromide, 30, 75 2-Methyl-5,6-pyrazinedicarboxylic acid,... [Pg.61]

Propionitrile, 51 -Propylacetylene, 17 2,3-Pyrazinedicarboxylic acid, 86 Pyridine, 3-amino, 3 Pyridine, 5-ethyl-2-methyl, 41 Pyruvic aldehyde-sodium bisulfite, 88... [Pg.58]

Methyl-2,3-pyrazinedicarbonitrile (13) gave 5-methyl-2,3-pyrazinedicarboxylic acid (14) (NaOH, H20—EtOH, reflux, 2 h 60% a little HCN due to a side reaction).477... [Pg.301]

Methyl-2,3-pyrazinedicarboxylic acid (24, Q = R = C02H) gave a mixture of 5-methyl-2-pyrazinecarboxylic acid (24, Q = H, R = C02H) and 6-methyl-2-pyrazinecarboxylic acid (24, Q = C02H, R = H), in which the former predominated (sublimed at 185°C under reduced pressure 72% before separation as derivatives).477... [Pg.303]

Palladium-catalyzed carbonylation of chloropyrazines in methanol and in amines yields the pyrazine carboxylic methyl esters and carboxamides, respectively. This procedure has been successfully applied to the synthesis of 2,5-pyrazinedicarboxylic acid derivatives and 3-methoxy-carbonylpyrazine 1-oxide from the corresponding dichloropyrazines and A-oxides <908923 >. [Pg.272]

See other pages where 2-Methyl-5,6-pyrazinedicarboxylic acid is mentioned: [Pg.58]    [Pg.59]    [Pg.58]    [Pg.59]    [Pg.2363]    [Pg.58]    [Pg.59]    [Pg.447]    [Pg.450]    [Pg.58]    [Pg.450]    [Pg.59]    [Pg.306]   
See also in sourсe #XX -- [ Pg.30 , Pg.89 ]

See also in sourсe #XX -- [ Pg.30 , Pg.89 ]

See also in sourсe #XX -- [ Pg.30 , Pg.89 ]

See also in sourсe #XX -- [ Pg.30 , Pg.89 ]

See also in sourсe #XX -- [ Pg.89 ]

See also in sourсe #XX -- [ Pg.30 , Pg.89 ]



SEARCH



2,3-Pyrazinedicarboxylic acid

© 2024 chempedia.info