تفاعل #61198

معادلة التفاعل

2-bromo-1-(2-trimethylsilanyl-ethoxymethyl)-1H-imidazole-4-carbonitrile

i-PrMgCl

ethyl cyanoformate

→

colorless oil

المردود 75.2%

4-Cyano-1-(2-trimethylsilanyl-ethoxymethyl)-1H-imidazole-2-carboxylic acid ethyl ester

المردود 75.2%

المذيبات

THF

THF

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةcooled to −78° C.
2. 2
   أخرىto attain RT
3. 3
   workup.STIRRINGstirred for 1 h
4. 4
   أخرىThe reaction was quenched with satd aq NH4Cl
5. 5
   workup.ADDITIONdiluted with EtOAc (20 mL)
6. 6
   غسيلwashed with brine (2×20 mL)
7. 7
   تجفيفthe organic layer was dried over Na2SO4
8. 8
   تركيزconcentrated
9. 9
   غسيلThe title compound was eluted from a 20-g SPE cartridge (silica) with 30% EtOAc/hexane

الإجراء التجريبي

To a solution of 2-bromo-1-(2-trimethylsilanyl-ethoxymethyl)-1H-imidazole-4-carbonitrile (0.55 g, 1.8 mmol) (as prepared in the previous step) in THF (6 mL) at −40° C. was added dropwise a solution of 2M i-PrMgCl in THF (1 mL). The reaction was allowed to stir for 10 min at −40° C. and then cooled to −78° C., and ethyl cyanoformate (0.3 g, 3.0 mmol) was added. The reaction allowed to attain RT and stirred for 1 h. The reaction was quenched with satd aq NH4Cl, diluted with EtOAc (20 mL) and washed with brine (2×20 mL), and the organic layer was dried over Na2SO4 and then concentrated. The title compound was eluted from a 20-g SPE cartridge (silica) with 30% EtOAc/hexane to give 0.40 g (74%) of a colorless oil. Mass spectrum (ESI, m/z): Calcd. for C13H21N3O3Si, 296.1 (M+H), found 296.1.

المصدر