By reduction of carboxylic acids

PREPARATION OF ALCOHOLS BY REDUCTION OF CARBOXYLIC ACIDS AND ESTERS... 

Section 15.3 Alcohols can be prepared from carbonyl compounds by reduction of carboxylic acids and esters. See Table 15.3. 

J. S. Cha, Recent Developments in the Synthesis of Aldehydes by Reduction of Carboxylic Acids and their Derivatives with Metal Hydrides, Org. Prep. Proced. Int. 1989, 21, 451- 477. 

Hydroxymethylpyrazines may be prepared by reduction of carboxylic acid derivatives. Thus reduction of 2-amino-3-methoxycarbonylpyrazine with lithium aluminum hydride in tetrahydrofuran gave 2-amino-3-hydroxymethylpyrazine (1074, 1075) the imide from 23-dicarboxypyrazine (20) with sodium borohydride in tetrahydrofuran gave 2-carbamoyl-3-hydroxymethylpyrazine (21), and the methylcarbamoyl analogue was prepared similarly (1076). 

Theoretically, it ought to be possible to prepare aldehydes by reduction of carboxylic acids. In practice, this is not possible with the reagent normally used to reduce a carboxylic acid, lithium aluminum hydride (UAIH4 or LAH). 

Sources of Alcohols 615 Preparation of Alcohols by Reduction of Aldehydes and Ketones 617 Preparation of Alcohols by Reduction of Carboxylic Acids 620 Preparation of Alcohols from Epoxides 620... 

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