Pyrazinecarboxylic esters reduction

Several reactions of pyrazinecarboxylic esters have been discussed already reduction to N-alkylpiperazines (Section 3.2.2.2), reduction to extranuclear hydrox-ypyrazines (Section 5.2.1), and hydrolysis to pyrazinecarboxylic acids (Section 8.1.1). Other reactions to be expected of carboxylic or carboximidic esters are typified in the following classified examples ... 

Most of the usual routes to such aldehydes have been covered already by primary synthesis in Chapters 1 and 2, by oxidation of alkylpyrazines in Section 3.2.4.1, by oxidation of hydroxymethylpyrazines, in Section 5.2.2, and by reduction of pyrazinecarboxylic esters in Section 8.2.2. 

Reactions of pyrazinecarbonitriles already discussed include photochemical alkanelysis (Section 3.2.1.3), reduction to aminomethylpyrazines (Section 7.3.1), hydrolysis to pyrazinecarboxylic acids (Section 8.1.1), alcohol addition to afford pyrazinecarboximidic esters (and thence hydrolysis to regular esters) (Section 8.2.1), and conversion into pyrazinecarboxamides or the like (Section 8.4.1). 

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