반응 #471157

반응 방정식

1H-Benzotriazolium

dimethylamine

methyl N-{(1R)-1-(benzofuran-5-yl)-2-[(2-hydroxyphenyl)amino]-2-oxoethyl}-L-leucinate

1,1′-thiocarbonyldiimidazole

→

methyl N-[1-(benzofuran-5-yl)-2-(dimethylamino)-2-oxoethyl]-L-leucinate

수율 40.5%

용매

tetrahydrofuran

dichloromethane

Water

반응 조건

후처리

1. 1
   workup.STIRRINGThe reaction mixture was stirred for a further 18 hours
2. 2
   세척eluting with a gradient (3:1 to 1:2 cyclohexane:ethyl acetate)
3. 3
   기타evaporated

실험 절차

A solution of methyl N-{(1R)-1-(benzofuran-5-yl)-2-[(2-hydroxyphenyl)amino]-2-oxoethyl}-L-leucinate (410 mg) and 1,1′-thiocarbonyldiimidazole (196 mg) in dichloromethane (5 ml) was left to stand for 18 hours. Water (20 □l) was added to the reaction mixture and this was then stirred rapidly for 30 minutes. After this, 1H-Benzotriazolium, 1-[bis(dimethylamino)methylene]-, tetrafluoroborate(1-), 3-oxide (TBTU, 710 mg) and a solution of dimethylamine in tetrahydrofuran (3 ml of 2M solution) were added. The reaction mixture was stirred for a further 18 hours and was then passed down an SPE (5 g, silica) eluting with a gradient (3:1 to 1:2 cyclohexane:ethyl acetate). The required fractions were combined and evaporated to furnish methyl N-[1-(benzofuran-5-yl)-2-(dimethylamino)-2-oxoethyl]-L-leucinate (140 mg).

출처