반응 #47072

반응 방정식

4-fluorobenzaldehyde

2-methyl-cis-4,5-diphenyl-4,5-dihydro-imidazole-1-carboxylic acid, tert-butyl ester

2-Methyl-cis-4,5-diphenyl-4,5-dihydro-imidazole-1-carboxylic acid, tert-butyl ester

n-butyl lithium

hexane

ammonium chloride

→

product 256

수율 45.8%

2-[2-(4-Fluorophenyl)-2-hydroxyethyl]-cis-4,5-diphenyl-4,5-dihydro-imidazole-1-carboxylic acid, tert-butyl ester

수율 45.8%

용매

THF

EtOAc

반응 조건

후처리

1. 1
   workup.STIRRINGthe mixture is stirred for 1 h at −70° C. and 1 h at RT
2. 2
   기타the organic layer is separated
3. 3
   세척washed with brine
4. 4
   건조dried (MgSO4)
5. 5
   여과filtered
6. 6
   기타the residue purified by chromatography on silica gel
7. 7
   세척elution with dichloromethane:EtOAc (9:1)

실험 절차

To a cold (−70° C.) solution of 2-methyl-cis-4,5-diphenyl-4,5-dihydro-imidazole-1-carboxylic acid, tert-butyl ester (253) (3.36 g, 10.0 mmol) in THF is added 1.6M n-butyl lithium in hexane (6.9 mL, 11.0 mmol), and the mixture is stirred for 1 h at −70° C. To the reaction mixture is added 4-fluorobenzaldehyde (1.18 mL, 11.0 mmol), and the mixture is stirred for 1 h at −70° C. and 1 h at RT. To the reaction mixture is added ammonium chloride solution, EtOAc, and the organic layer is separated, and washed with brine, dried (MgSO4), and filtered. The filtrate is rotary evaporated, and the residue purified by chromatography on silica gel; elution with dichloromethane:EtOAc (9:1) gives 2.11 g of the product 256. 1H NMR (CDCl3) δ 7.60-7.45 (m, 2 H), 7.15-6.90 (m, 10 H), 6.85-6.60 (m, 2 H), 5.70-5.20 (m, 4 H), 3.60-3.10 (m, 2 H), 1.18 (s, 9 H); MS: m/z 461 (M++1).

출처