摘要 |
<p>Preparation of 2-acetylcarboxylic acid esters (I) comprises condensation of an acetic acid ester with an aldehyde, followed by removal of any unreacted educts and water formed during condensation and hydrogenation of the resulting intermediate. Preparation of 2-acetylcarboxylic acid esters (I) comprises reacting an acetic acid ester with an aldehyde, followed by hydrogenation. The novelty comprises four factors: (1) During the first stage, the use of acetic acid 1-6C alkyl esters and 1-12C aldehydes, in the presence of a condensation catalyst at 0-40 degrees C; (2) Removal of any unreacted educt and any water produced after the condensation has taken place; (3) Hydrogenation of the residue in the presence of a catalyst at 20-160 degrees C and 1-100 bar, where the hydrogenation is divided into two stages, with the first stage taking place at 20-90 degrees C and the second at 50-160 C; and (4) Isolation of (I) by distillation.</p> |