A nitrous acid salt is added at a temperature of 10 to 80° C. to an aqueous solution which contains an optically active 2-aminocarboxylic acid (4) and a protonic acid, the amount of the latter acid being 1 to 3 equivalents to the former, and which has a proton concentration of 0.5 to 2 mol/kg to conduct a reaction to thereby produce an optically active 2-hydroxycarboxylic acid (1). Thionyl chloride and a basic compound are caused to act on the compound (1) to chlorinate it and simultaneously invert the configuration in the 2-position. Thus, an optically active 2-chlorocarboxylic acid chloride (5) is induced. The compound (5) is hydrolyzed to induce an optically active 2-chlorocarboxylic acid (2). The compound (2) is reacted with a thioacetic acid salt to incorporate an acetylthio group thereinto and simultaneously invert the configuration in the 2-position to thereby produce an optically active 2-acetylthiocarboxylic acid (3).
1
在温度为10至80°C的
水溶液中,加入一种
亚硝酸盐,该
水溶液含有一个光学活性的2-
氨基
羧酸(4)和一个质子酸,后者的量为前者的1至3当量,并且具有0.5至2mol/kg的质子浓度,以进行反应从而产生一个光学活性的2-羟基
羧酸(1)。然后,使亚
硫酰氯和一种碱性化合物作用于化合物(1)以进行
氯化,并同时颠倒2位构型。因此,诱导出一个光学活性的2-
氯羧酸氯化物(5)。化合物(5)经
水解产生一个光学活性的2-
氯羧酸(2)。将化合物(2)与
硫乙酸盐反应以在其中引入一个乙酰
硫基团,并同时颠倒2位构型,从而产生一个光学活性的2-乙酰
硫基
羧酸(3)。