5-Bromo-3,6-diisobutyl- 2 pyrazinone

Iodo-3,6-diisobutyl-2(l//)-pyrazinone (133) gave 3,6-diisobutyl-5-phenylethynyl-2 (1/0-pyrazinone (134) (Cu( =CPh, pyridine, reflux, 6 h 67% after separation from unchanged substrate (23%) the corresponding chloro and bromo substrates gave much lower yields under comparable conditions.321... 

Bromo-5,6-dichloro-2-pyrazinamine 3-Bromo-5,6-dichloro-2(177)-pyrazinone 5-Bromo-3,6-diethyl-2(77)-pyrazinone 5-Bromo-3,6-diisobutyl-2(177)-pyrazinone 5-Bromo-3,6-diisobutyl-2(177)-pyrazinone... 

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