Replacement of Halogeno Substituents by Alkylthio Groups

Halogenopyrazines react with alkylthiolate ions to give alkylthiopyrazines, by replacement of one or, in some cases, two halogeno substituents the reaction is usually carried out at reflux or at elevated temperatures in sealed tubes. The following pyrazines have been prepared by these methods from the chloropyrazines unless otherwise specified 2-ethylthio and 2-isopropylthio (668a) 2-methyl-3-methylthio (735, 844,977) 2-methyl-5(and 6)-methylthio (735) 2,5-dimethyl-3-methyl(ethyl, 

2- carbamoyl-6-phenylthio (992) 2-amino-6-methylthio (or 6-ethylthio) (994) variously substituted 2-amino-3-alkoxycarbonylmethylthio(995) 2-amino-5-chloro- 

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