Carbon tetrabromide → Methyl 4-bromo-2-(tert-butoxycarbonylamino)butanoate

HRID 910720노트

반응식

HRID 910720 반응식
C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.[CH3:20][O:21][C:22](=[O:35])[C@H:23]([CH2:32][CH2:33]O)[NH:24][C:25]([O:27][C:28]([CH3:31])([CH3:30])[CH3:29])=[O:26].C(Br)(Br)(Br)[Br:37]>C(Cl)Cl>[CH3:20][O:21][C:22](=[O:35])[CH:23]([NH:24][C:25]([O:27][C:28]([CH3:31])([CH3:30])[CH3:29])=[O:26])[CH2:32][CH2:33][Br:37]

참가 물질

5

반응물 3

HCID 11205Carbon tetrabromideHCID 11776TriphenylphosphineHCID 10561607Methyl N-(tert-butoxycarbonyl)-L-homoserinate

생성물 1

HCID 6857808Methyl 4-bromo-2-(tert-butoxycarbonylamino)butanoate수율 20.2%

시약·촉매·용매 1

HCID 6344Dichloromethane용매2회

실험 절차

A solution of triphenylphosphine (2.20 g, 8.39 mmol) in dry CH2Cl2 (20 mL) was added dropwise via syringe to a solution of N-Boc homoserine methyl ester 18 (8.39 mmol) and carbon tetrabromide (4.18 g, 12.60 mmol) in dry CH2Cl2 (20 mL). The resulting dark solution was stirred at room temperature for 16 h. Hexanes was added and precipitates were removed by suction filtration. The filtrate was concentrated under reduced pressure and subject to flash silica gel column chromatography using ethyl acetate/hexanes (1:10, v/v then 1:6, v/v) to give the desired product 19 as a yellow oil (501 mg, 20% overall yield from homoserine). 1H NMR (300 MHz, CDCl3) δ 1.45 (s, 9H), 2.12-2.48 (m, 2H), 3.39-3.47 (m, 2H), 3.78 (s, 3H), 4.33-4.48 (m, 1H), 5.10-5.22 (m, 1H). m/z (ESI) 296 [C10H18BrNO4+H]+.

후처리

  1. customprecipitates
  2. customwere removed by suction filtration
  3. concentrationThe filtrate was concentrated under reduced pressure

출처 및 근거

ORD 기록
ord-38662dda70e941f381e5b463ab401078
출처 데이터셋
uspto-grants-2011_09
특허 번호
US08022210B2

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