تفاعل #89730

معادلة التفاعل

Lithium hexamethyldisilazide

1-benzyl 4-methyl(2S)-2-[benzyl((2R)-2-(1-ethoxyethoxy)-3-[(4-methylphenyl)sulfonyl]oxypropyl)amino]succinate

toluene

→

product

المردود 78.2%

2-benzyl 3-methyl(2S,3S,5S)-1-benzyl-5-(1-ethoxyethoxy)piperidine-2,3-dicarboxylate

المردود 78.2%

المذيبات

tetrahydrofuran

tetrahydrofuran

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةto warm up to at 0 Celsius gradually
2. 2
   workup.STIRRINGstirred at 0 Celsius for 30 min
3. 3
   أخرىAfter quenched with aq ammonium chloride
4. 4
   استخلاصthe mixture was extracted with ethyl acetate
5. 5
   غسيلThe combined organic layers were washed with water, brine
6. 6
   تجفيفdried (sodium sulfate)
7. 7
   تركيزconcentrated
8. 8
   أخرىto dry
9. 9
   أخرىThe residue was purified on silica gel column
10. 10
    غسيلeluting with 0 to 20% EtOAc in hexane

الإجراء التجريبي

To a solution of 1-benzyl 4-methyl(2S)-2-[benzyl((2R)-2-(1-ethoxyethoxy)-3-[(4-methylphenyl)sulfonyl]oxypropyl)amino]succinate (34.30 g, 0.05464 mol) in a mixture of tetrahydrofuran (90.0 mL, 1.11 mol) and toluene (470.0 mL, 4.412 mol) at −78 Celsius was added 1.00 M of Lithium hexamethyldisilazide in tetrahydrofuran (65.6 mL). The resulting mixture was stirred at −78 Celsius overnight, and then allowed to warm up to at 0 Celsius gradually and stirred at 0 Celsius for 30 min. After quenched with aq ammonium chloride, the mixture was extracted with ethyl acetate. The combined organic layers were washed with water, brine, and dried (sodium sulfate), and concentrated to dry. The residue was purified on silica gel column, eluting with 0 to 20% EtOAc in hexane, to yield the cyclized product (19.47 g, 78.2%). MS (ESI): (M+H)+=456.0.

المصدر