Hydrochloric Acid → 6,7-Dichloro-2,3-dimethoxyquinoxaline-5-boronic acid

HRID 842664노트

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HRID 842664 반응식
O1CCCC1.C([N-]C(C)C)(C)C.[Li+].[Cl:14][C:15]1[CH:16]=[C:17]2[C:22](=[CH:23][C:24]=1[Cl:25])[N:21]=[C:20]([O:26][CH3:27])[C:19]([O:28][CH3:29])=[N:18]2.[B:30](OC)([O:33]C)[O:31]C.Cl>O1CCCC1.O>[Cl:25][C:24]1[C:15]([Cl:14])=[CH:16][C:17]2[N:18]=[C:19]([O:28][CH3:29])[C:20]([O:26][CH3:27])=[N:21][C:22]=2[C:23]=1[B:30]([OH:33])[OH:31]

참가 물질

7

반응물 4

HCID 313Hydrochloric AcidHCID 8470Trimethyl borateHCID 10997623Lithium diisopropylamide mono(tetrahydrofuran)HCID 120471106,7-Dichloro-2,3-dimethoxyquinoxaline

생성물 1

HCID 120471116,7-Dichloro-2,3-dimethoxyquinoxaline-5-boronic acid수율 26.1%

시약·촉매·용매 2

HCID 962Water용매HCID 8028Tetrahydrofuran용매

실험 절차

Lithium diisopropylamide mono(tetrahydrofuran) (1.5M in cyclohexane, 6.18 mL, 9.26 mmol) was added to a stirred suspension of 6,7-dichloro-2,3-dimethoxyquinoxaline (Preparation 1, 2.0 g, 7.72 mmol) in dry tetrahydrofuran (150 mL) at −78° C., under nitrogen. After 1 hour at −78° C., trimethyl borate (1.47 mL, 2.0 g, 19.3 mmol) was added. The solution was stirred for a further 1 hour and then left to reach room temperature over 18 hours. Water (50 mL) was added, the solution was acidified to pH 1 with 2M aqueous hydrochloric acid solution and extracted with dichloromethane (3×150 mL). The combined organic extracts were dried (MgSO4) and concentrated under reduced pressure. The residue was purified by flash chromatography on silica gel, by gradient elution using dichloromethane:methanol (100:0 changing to 99:1, by volume) as the eluent to afford 6,7-dichloro-2,3-dimethoxyquinoxaline-5-boronic acid (0.610 g, 26%) as a light brown solid.

후처리

  1. waitleft
  2. waitto reach room temperature over 18 hours
  3. extractionextracted with dichloromethane (3×150 mL)
  4. dry with materialThe combined organic extracts were dried (MgSO4)
  5. concentrationconcentrated under reduced pressure
  6. customThe residue was purified by flash chromatography on silica gel, by gradient elution

출처 및 근거

ORD 기록
ord-e14c38ab15434c38a0149fee9cdf3a55
출처 데이터셋
uspto-grants-2002_04
특허 번호
US06376490B1

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