ES411340A1 - Procedure for the preparation of new derivatives of 3-butenoic and 2-butenoic acids. (Machine-translation by Google Translate, not legally binding) - Google Patents

Abstract

Procedure for the preparation of new derivatives of 3-butenoic and 2-butenoic acids of the general formula I **(See formula)** wherein the radical means a branched or unbranched alcohol radical with 1 to 7 carbon atoms, a 5-, 6- or 7-membered cycloalkyl or cycloalkenyl radical, the piperidino radical or a phenyl radical, which may optionally be substituted by one or two halogen atoms, a nitro or cyano group, or an amino group optionally substituted by an aliphatic acyl radical with 1 to 4 carbon atoms, the radical R3 means a hydrogen atom, a halogen atom or, if R1 has the meanings indicated above with the exception of that of an optionally substituted phenyl radical, represents a nitro, amino or cyano group, with the proviso that R3 does not mean any hydrogen atom when R1 represents an unsubstituted phenyl radical, and the radical B means the hydroxy group, an alkoxy radical with 1 to 4 carbon atoms or a radical of the general formula II, **(See formula)** in which R4 and R5, which may be the same or different, represent hydrogen atoms, or, in case R1 means an optionally substituted phenyl radical as defined above, they also represent alcohol radicals with 1 to 5 carbon atoms, in this case R4 may also be a hydroxyphenyl radical when R5 represents a hydrogen atom and radical A represents bivalent radicals (see formula) in which R2 represents a hydrogen atom or an alcohol radical with 1 to 2 carbon atoms, as well as, if B is the hydroxy group, its physiologically compatible salts with organic or inorganic bases and, in the case of that R1 contains a basic radical or R3 means a basic group, of its physiologically compatible salts with organic or inorganic acids, characterized in that for the preparation of the free acids of the general formula I, 4-hydroxy acids are heated to 140 to 200ºC -butyrics, their salts, esters or amides of the general formula III **(See formula)** wherein R1 to R3 and B are as defined above, in the presence of halohydric acid salts of tertiary organic bases, the end products are separated in a known manner; and a mixture of 2-butenoic and 3-butenoic acids obtained is then separated, if desired, by physical methods into the 2-butenoic and 3-butenoic acids of the general formula I and optionally at the same time separated into the cis and trans of these acids, and/or compounds obtained from the general formula I, in which B is the hydroxy group, are transformed, if desired, into compounds of the general formula I, in which B represents an alkoxy group, and/or Compounds of the general formula I, in which B means a halogen atom or an alkoxy group, are transformed with an amine of the general formula VIII **(See formula)** in the amides of the general formula I, and/or if desired acids of the general formula I are transformed with organic or inorganic bases in their salts, and the compounds of the general formula I, in which R1 contains a basic radical or R3 means basic radicals, they are transformed if desired into their salts by the addition of acid with organic or inorganic acids. (Machine-translation by Google Translate, not legally binding)