VERSATILE AND STEREOSPECIFIC SYNTHESIS OF GAMMA,DELTA -UNSATURATED AMINO ACIDS BY WITTIG REACTION

摘要

The γ,δ-unsaturated α-amino acids of general formula (I). Also, a versatile process for the stereospecific synthesis of said compounds of formula (I), involving a Wittig reaction. Further, intermediate products of general formulae (II) and (III), as shown below, which are involved in the synthesis of compounds (I).;Compounds of general formula (I) may be useful as therapeutic substances, or as reagents or intermediates for fine chemistry.

主权项

1. A process for producing a compound of formula (I), comprising performing a Wittig reaction by reacting a phosphonium salt of general formula (II) whereinR1 represents a hydrogen atom or R5, wherein R5 is a substituted or unsubstituted group selected from the group consisting of alkyl, cycloalkyl, aryl, and alkenyl;R2 and R3 may be the same or different and represent each a hydrogen atom or a substituted or unsubstituted group selected from the group consisting of alkyl, cycloalkyl, aryl, alkenyl, and —COR, wherein R is a substituted or unsubstituted group selected from the group consisting of alkyl, cycloalkyl, aryl, alkenyl, alkyloxy, cycloalkyloxy, and aryloxy;R4 represents a substituted or unsubstituted group selected from the group consisting of alkyl, cycloalkyl, aryl, and alkenyl; with compound (IV), wherein compound (IV) is selected in the group consisting of a ketone or aldehyde of formula RaCORb, an imine of formula RaRbC═NRc, a [Ra,Rb]-trisubstituted trioxane and a RaRbC(OH)(SO3Na); wherein Ra and Rb may be the same or different and represent each a hydrogen atom or a substituted or unsubstituted group selected from the group consisting of alkyl, alkenyl, cycloalkyl, aryl, metallocenyl and —COR, wherein R is a substituted or unsubstituted group selected from the group consisting of alkyl, cycloalkyl, aryl, alkenyl, alkyloxy, cycloalkyloxy and aryloxy; and wherein Rc represents a hydrogen atom, a substituted or unsubstituted group selected from the group consisting of alkyl, cycloalkyl, and aryl or an electroattractive group; in the presence of a weak base and of a solvent suitable for phase transition conditions, resulting in compound (I), wherein the weakbase is selected in the group consisting of Cs2CO3, Li3PO4, NaH, K3PO4 and K2CO3.