摘要:
3,3-Dimethylbutanal is prepared from 3,3-dimethylbutanol. Intermediate 3,3-dimethylbutanol is obtained by reacting ethylene, isopropylene and a mineral acid to produce a 3,3-dimethylbutyl ester which is hydrolyzed to the alcohol. The hydrolysis step is effectively carried out by reactive distillation. Alternatively, 3,3-dimethylbutanal is prepared from 3,3-dimethylbutanol obtained by reduction of the corresponding carboxylic acid or 1,2-epoxy-3,3-dimethylbutane, or by hydrolysis of 1-halo-3,3-dimethylbutane. Fixed bed gas phase and stirred tank liquid phase processes are provided for converted 3,3-dimethylbutanol to 3,3-dimethylbutanal by catalytic dehydrogenation.
摘要:
Methods for preparing (S)-N-tert-butyl-1,2,3,4-tetrahydro-3-isoquinoline-carboxamide ("tic-c"), and converting tic-c to (S)-decahydroisoquinoline-3-carboxylic acid t-butylamide ("tic-d") are disclosed. The initial step in the formation of tic-c involves the phosgenation of a substituted tetrahydroisoquinoline to form an N-carboxy anhydride. Tic-d is used as an intermediate in the synthesis of known compounds having pharmaceutical activity.
摘要:
The present invention is an improved process for the synthesis of asparagine, a non-essential amino acid useful in food and medical applications. The process utilizes mineral acid to make an intermediate beta-methyl aspartate from a reaction mixture of aspartic acid and methanol. The intermediate product is then amminated in situ and asparagine collected with no need for an isolation step of the intermediates.