反应详情

温度

80 °C

To a solution of (±)-7-(2,5-dichlorothiophen-3-yl)-5-guanidinoimino-4-methyl-5,6,7,8-tetrahydroquinoline (17.4 g) in ethanol (200 ml) was added a solution of L-pyroglutamic acid (4.0 g) in ethanol (20 ml), at 80° C., and the mixture was gradually cooled to the room temperature and stirred at room temperature for 6 hours. The crystals were filtered and washed with ethanol to give (+)-7-(2,5-dichlorothiophen-3-yl)-5-guanidinoimino-4-methyl-5,6,7,8-tetrahydroquinoline L-pyroglutamate (11.0 g). Said crystals were suspended in methanol (200 ml), and to the mixture was added a solution of 28% sodium methoxide in methanol (4.2 ml). Under reduced pressure, the solvent was evaporated to give crystals, which were washed with water, dried and recrystallized from ethanol. To the crystals was added ethanol (30 ml), and then methanesulfonic acid (3.4 g). The mixture was heated to give a homogenous solution and cooled, and precipitated crystals were filtered to give (+)-7-(2,5-dichlorothiophen-3-yl)-5-guanidinoimino-4-methyl-5,6,7,8-tetrahydroquinoline methanesulfonate (Compound 111) (8.5 g, 99.9% ee).

1. filtrationThe crystals were filtered
2. washwashed with ethanol