2-Acetoxymethyl-6-methylpyrazine

Dimethylpyrazine 1-oxide (280) gave 2-acetoxymethyl-3-methylpyrazine (281) (neat Ac20, reflux, 30 min 77%) 1272 the isomeric 2,6-dimethyl-pyrazine 1-oxide gave a separable mixture of 2-acetoxymethyl-6-methylpyrazine (282, R = Ac) and 2-hydroxymethyl-6-methylpyrazine (282, R = H), the latter arising presumably by hydrolysis during the work up (neat Ac20, reflux, 1 h 40 and 12%, respectively).1307... 

Acetoxymethyl- -chloropyrazine 2-Acetoxymethyl-3,6-dichloro-5-methylpyrazine 2-Acetoxymethyl-3,6-dichloro-5-methylpyrazine 1-oxide 2-Acetoxymethyl-3-ethoxypyrazine 2-Acetoxymethyl-5-isobutyl-3-methoxypyrazine 2-Acetoxymethyl-5-isobutyl-3-methoxypyrazine 1-oxide 2-Acetoxymethyl-3-methoxy-5-methylpyrazine 2-Acetoxymethyl-5-methoxy-6-methylpyrazine 2-Acetoxymethyl-3-methoxy-5-methylpyrazine 1-oxide 2-Acetoxymethyl-3-methylpyrazine 2-Acetoxymethyl-5-methylpyrazine... 

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... 

Dimethylpyrazine gave successively its 1-oxide (258) (H202), 2-acetoxymethyl-5-methylpyrazine (259, R = Ac), 2-hydroxymethyl-5-methylpyrazine (259, R = H) (HO ), and 5-methyl-2-pyrazinecarboxyhc acid (260) (KMn04 for details of all stages in this indirect route, see original paper).432... 

Chloromethyl-5-methylpyrazine (242) gave either 2-acetoxymethyl- (243) (AcOK, EtOH, reflux, 6 h 65%) or 2-hydroxymethyl-5-methylpyrazine (224) (AcOK, KHC03, EtOH, reflux, 6 h 74%) 221 the acetoxymethyl intermediate was confirmed as such by alkaline hydrolysis to the product (244) (NaOH, no details 85%).1353... 

Acetoxymethyl- (126) gave 2-hydroxymethyl-3-methoxy-5-methylpyrazine (127) (K2C03, MeOH—H20, 20°C, 24 h 89%).324... 

Methoxy-3,6-dimethylpyrazine 4-oxide (283) gave only 2-acetoxymethyl-3-methoxy-5-methylpyrazine (284) (neat AC2O, reflux, 1 h 88%) 324 in contrast, the homologous substrate, 2,5-dibenzyl-3-methoxypyrazine 1-oxide (285), gave a separable mixture of 2-(a-acetoxybenzyl)-5-benzyl-3-methoxy-pyrazine (286) and 2-acetoxy-3,6-dibenzyl-5-methoxypyrazine (287) (neat Ac20, reflux, 90 min 55 and 20%, respectively).312... 

Acetoxymethyl-6-methylpyrazine 2-Acetoxymethyl-5-methylpyrazine 1,4-dioxide 2-Acetoxymethyl-5-methylpyrazine 1-oxide 2-Acetoxymethyl-5-methylpyrazine 4-oxide 2- Acetoxymethyl-5-phenylpyrazine 2-Acetoxymethyl-6-phenylpyrazine... 

Dimethylpyrazine 1-oxide, 2-acetoxymethyl-5-methylpyrazine 1-oxide, and 2,Sdiacetoxyinethylpyrazine (prolonged heating) 760... 

Dimethylpyrazine 1,4-dioxide 2-Acetoxymethyl-6-methylpyrazine and 2,6-dimethylpyrazine 4-oxide 760... 

Peroxyacetic acid oxidation of 2-acetoxymethyl-5-methylpyrazine gave the 1,4-dioxide which hydrolyzed in 0.1% sulfuric acid to 2-hydroxymethyl-5-methyl-pyrazine 1,4-dioxide (625) and 2,3-di(acetoxymethyl)pyrazine 1,4-dioxide was subjected to transesterification with lower alcohols in the presence of a catalytic amount of alkali to give 2,3-di(hydroxymethyl)pyrazine 1,4-dioxide (739). 

Amino-3-cyano-5-methylpyrazine 1,4-dioxide (91) refluxed for several minutes with acetic anhydride formed 3-acetamido-2-cyano-5-hydroxy-6-methylpyrazine 1-oxide (92) (24%) (532) and 2-acetoxymethyl-5-methylpyrazine 1,4-dioxide refluxed with acetic anhydride afforded a mixture of2,5-di(acetoxymethyl)pyrazine 1-oxide, with some 2,5-diacetoxymethylpyrazine and a monoxide of 2-acetoxy-methyl-5-methylpyrazine (625). 2-Formylpyrazine hydrate 1,4-dioxide with aqueous sodium hydroxide or bicarbonate at < 37° in an unusual reaction gave 3-carboxy-pyrazine 1-oxide mixed with 5 [Pg.188]

---