反应详情

Examples of the aldehyde of the general formula (1) include trimethylacetaldehyde, 2,2-dimethylbutanal, 2-ethyl-2-methylbutanal, 2,2-dimethyl-4-pentenal, 2,2-dimethylpentanal, 2,2-dimethylpenta-3,4-dienal and the like. Particularly, trimethylacetaldehyde (boiling point 74° C. at 730 mmHg) and 2,2-dimethy-4-pentenal (boiling point 124° C. at 760 mmHg) are preferable examples of the invention because the both substances themselves and the corresponding alcohols formed at the preparation of vitamin A aldehyde as side products have lower boiling points, so that these materials can be easily removed from the reaction mixtures at lower temperatures after the completion of the reaction.