申请人:Societe Nationale des Poudres et Explosifs
公开号:US04782164A1
公开(公告)日:1988-11-01
The invention relates to a new process for preparing active esters or carboxylic acids, which consists in reacting a carboxylic acid, in the presence of an agent for binding hydrohalic acid, with a carbonate of formula: ##STR1## in which R.sup.1 denotes either a radical of formula ##STR2## in which R.sup.3 and R.sup.4, which may be identical or different, are not hydrogen atoms and denote organic radicals which may be substituted or unsubstituted and saturated or unsaturated, and may be or may not be bound to a polymer, and which can be joined together to form a hetero-cyclic system with the nitrogen atom, or a substituted or unsubstituted aryl radical which may or may not be bound to a polymer, R.sup.2 denotes a hydrogen atom, an aliphatic or cycloaliphatic radical which may be substituted or unsubstituted and saturated or unsaturated, or a substituted or unsubstituted aromatic radical, and X denotes a halogen atom. This process is especially useful for the synthesis of active esters of N-protected amino acids. The invention also relates to the new carbonates described above and the method of producing them, which consists in reacting an alpha-halogenated chloroformate of formula: R.sup.2 --CHX--O--COCl with an alcohol of formula R.sup.1 OH in an inert solvent medium of the presence of an organic or inorganic base.
该发明涉及一种制备活性酯或羧酸的新工艺,其包括在存在结合氢卤酸的试剂的情况下,将羧酸与下式的碳酸酯反应:##STR1## 其中R.sup.1表示以下式的基团之一:##STR2## 其中R.sup.3和R.sup.4,可以相同也可以不同,不是氢原子,并且表示可以被取代或未取代、饱和或不饱和的有机基团,可以或不可以与聚合物结合,并且可以结合在一起形成与氮原子形成杂环系统的杂环系统,或者是可以或不可以与聚合物结合的取代或未取代芳基基团,R.sup.2表示氢原子、可以被取代或未取代、饱和或不饱和的脂肪或环脂基团,或者是取代或未取代的芳基基团,X表示卤素原子。该工艺特别适用于合成N-保护氨基酸的活性酯。该发明还涉及上述新碳酸酯及其制备方法,其包括在有机或无机碱的存在下,在惰性溶剂介质中,将下式的α-卤代氯甲酸酯:R.sup.2 --CHX--O--COCl 与下式的醇:R.sup.1 OH 反应。