تفاعل #620488

معادلة التفاعل

Iodomethane

Water

(2-bromo-4-methyl-thiazol-5-yl)-carbamic acid tert-butyl ester

NaH

→

desired product

المردود 54.0%

(2-bromo-4-methyl-thiazol-5-yl)-methyl-carbamic acid tert-butyl ester

المردود 54.0%

المذيبات

ethyl acetate

DMF

ظروف التفاعل

المعالجة

1. 1
   workup.STIRRINGstirred for 5 h
2. 2
   أخرىthe resulting biphasic mixture was separated
3. 3
   استخلاصThe aqueous layer was extracted one time with ethyl acetate
4. 4
   غسيلThe combined organic extracts were washed twice with brine
5. 5
   تجفيفdried over Na2SO4
6. 6
   ترشيحfiltered
7. 7
   تركيزconcentrated to dryness under reduced pressure
8. 8
   أخرىThe crude product was purified by silica gel chromatography (0-100% ethyl acetate/hexanes)

الإجراء التجريبي

To a solution of (2-bromo-4-methyl-thiazol-5-yl)-carbamic acid tert-butyl ester (2.93 g, 10 mmol) in DMF (50 mL) at 0° C. was added NaH (480 mg, 12 mmol, 60% dispersion in mineral oil) in one portion and the suspension was stirred for 1 h. Iodomethane (0.65 mL, 10.5 mmol) was added in one portion, and after 5 min the reaction mixture was warmed to ambient temperature and stirred for 5 h. Water and ethyl acetate were added and the resulting biphasic mixture was separated. The aqueous layer was extracted one time with ethyl acetate. The combined organic extracts were washed twice with brine, dried over Na2SO4, filtered and concentrated to dryness under reduced pressure. The crude product was purified by silica gel chromatography (0-100% ethyl acetate/hexanes) to give the desired product as a clear oil (1.66 g, 54%): IR (KBr) 1688 cm−1; 1H NMR (300 MHz, CDCl3) δ 2.98 (s, 3H), 2.29 (s, 3H), 1.54 (s, 9H); ESIMS m/z 309 (M+2).

المصدر