تفاعل #46085

معادلة التفاعل

DBU

product

1(R)-tert-butoxycarbonylamino-2(S)-vinyl-cyclopropanecarboxylic acid

CDI

cyclopropylsulfonamide

→

title compound

المردود 92.0%

cyclopropanesulfonic acid (1-(R)-tert-butoxycarbonylamino-2-(S)-vinylcyclopropanecarbonyl)-amide

المردود 92.0%

المذيبات

THF

THF

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةat reflux for 50 minutes under nitrogen
2. 2
   أخرىThe mixture was quenched with 1N HCl to pH 1 and THF
3. 3
   تركيزwas concentrated in vacuo
4. 4
   استخلاصThe suspension was extracted with ethyl acetate (2×50 mL)
5. 5
   تجفيفthe combined organic extracts were dried (Na2SO4)
6. 6
   ترشيحfiltered
7. 7
   تركيزconcentrated
8. 8
   أخرىPurification by recystallization from hexanes-ethyl acetate (1:1)

الإجراء التجريبي

A solution of the product of Step 1 (2.62 g, 11.5 mmol) and CDI (2.43 g, 15.0 mmol) in THF (40 mL) was heated at reflux for 50 minutes under nitrogen. The solution was cooled to room temperature and transferred by cannula to a solution of cyclopropylsulfonamide (1.82 g, 15.0 mmol) in THF (10 mL). To the resulting solution was added DBU (2.40 mL, 16.1 mmol) and stirring was continued for 20 hours. The mixture was quenched with 1N HCl to pH 1 and THF was concentrated in vacuo. The suspension was extracted with ethyl acetate (2×50 mL) and the combined organic extracts were dried (Na2SO4), filtered, and concentrated. Purification by recystallization from hexanes-ethyl acetate (1:1) afforded the title compound (2.4 g) as a white solid. The mother liquor was purified by a Biotage 40S column (eluted 9% acetone in dichloromethane) to give a second batch of the title compound (1.1 g). Both batches were combined (total yield 92%). 1H NMR (DMSO-d6) δ 0.96-1.10 (m, 4H), 1.22 (dd, J=5.5, 9.5 Hz, 1H), 1.39 (s, 9H), 1.70 (t, J=5.5 Hz, 1H), 2.19-2.24 (m, 1H), 2.90 (m, 1H), 5.08 (d, J=10 Hz, 1H), 5.23 (d, J=17 Hz, 1H), 5.45 (m, 1H), 6.85, 7.22 (s, NH (rotamers); MS m/z 331 (M++H).

المصدر