Process for the preparation of alpha-(N-pyrrolyl)-derivative acids, the
申请人:Antibioticos, S.A.
公开号:US04563477A1
公开(公告)日:1986-01-07
A process for the preparation of alpha-(N-pyrrolyl)-derivative acids, the salts and esters thereof, of the formula ##STR1## in which R, R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are hydrogen atoms or substituted or unsubstituted alkyl, aryl, alkylaryl or heterocyclic radicals and R' is a metal cation, an organic base or an organic radical, wherein the corresponding amino ester is reacted with a dialkoxytetrahydrofuran or a derivative thereof. Certain compounds comprised among those corresponding to the above formula, particularly the DL, D and L-alpha-(N-pyrrolyl)-phenylacetic acids and certain esters thereof. Therapeutical compositions containing such compounds as active ingredient and therapeutical applications of said compounds.
[EN] SELF-CONDENSATION OF ALDEHYDES<br/>[FR] AUTO-CONDENSATION D'ALDÉHYDES
申请人:EASTMAN CHEM CO
公开号:WO2020101902A1
公开(公告)日:2020-05-22
An efficient process useful for the self-condensation of aliphatic aldehydes is provided, catalyzed by dialkylammonium carboxylate salts. In particular, the invention provides a facile method for the preparation of 2-ethyl hexenal via the self-condensation of butyraldehyde using various dialkylammonium carboxylates, e.g., diisopropylammonium acetate or dimethylammonium acetate, as catalyst. Additionally, residual nitrogen arising from the catalyst can be reduced to -100 ppm levels in the product via a simple washing procedure. The invention provides a process for preparing alkenals under conditions which limit the formation of undesired impurities and high-boiling oligomeric substances.