2- Acetoxy-6-methoxypyrazine

Methoxypyrazine 4-oxide (273) gave 2-acetoxy-6-methoxypyrazine (272) (neat AccO, reflux, A, 2 h 60%) or 2-acetoxy-3-methoxypyrazine (274) (Ac20, Et3N, reflux, A, 2 h 63%).1575... 

Acetoxy-3,6-dibenzyl-5-methoxypyrazine gave 3,6-di benzyl-5-methoxy-2(l//) -pyrazinone (29) (K2C03, MeOH—H20, reflux, 30 min > 95%) 312 2,5-diace-toxy-3,6-dimethylpyrazine gave 5-hydroxy-3,6-dimethyl-2(l//)-pyrazinone (30) (KHC03, MeOH, reflux, 50 min 53%).1386... 

Acetoxy-6-acetoxymethyl-3-isobutyl-5-methoxypyrazine (130) gave 6-hydrox-ymcthyl-3-isobutyl-5-methoxy-2(l//)-pyrazinone (131) (K2C03, MeOH—H20, 20°C, 30 min 97% note hydrolysis of both nuclear and extranuclear acetoxy groupings).329... 

Diisobutyl-3-methoxypyrazine 1-oxide (277) gave a separable mixture of 2-acetoxy-3,6-diisobutyl-5-methoxypyrazine (278) and 2-(l-acetoxy-2-methyl-propyl)-5-isobutyl-3-methoxypyrazine (279) (neat Ac20, reflux, 90 min 73 and 12%, respectively).310... 

Deoxygenation with formation of Chloro-, Acetoxy-, and Methoxypyrazines... 

Methoxy-3,6-dimethylpyrazine 4-oxide (283) gave only 2-acetoxymethyl-3-methoxy-5-methylpyrazine (284) (neat AC2O, reflux, 1 h 88%) 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 AC2O, reflux, 90 min 55 and 20%, respectively). ... 

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