Diethyl Carbonate → Ethyl 2-(4-broMopyridin-2-yl)acetate

HRID 1425990ノート

反応式

HRID 1425990 の反応式
C([N-]C(C)C)(C)C.[Li+].[Br:9][C:10]1[CH:15]=[CH:14][N:13]=[C:12]([CH3:16])[CH:11]=1.[C:17](=O)([O:21]CC)[O:18][CH2:19][CH3:20]>O1CCCC1>[CH2:19]([O:18][C:17](=[O:21])[CH2:16][C:12]1[CH:11]=[C:10]([Br:9])[CH:15]=[CH:14][N:13]=1)[CH3:20]

参加物

5

反応物 3

HCID 7766Diethyl CarbonateHCID 2724682Lithium diisopropylamide2 回HCID 27628354-Bromo-2-methylpyridine

生成物 1

HCID 53419398Ethyl 2-(4-broMopyridin-2-yl)acetate

試薬・触媒・溶媒 1

HCID 8028Tetrahydrofuran溶媒

反応条件

温度
-70 °C

実験手順

Lithium diisopropylamide (2 mol/L in tetrahydrofuran/heptane/ethylbenzene, 3.00 mL) was added to a solution of 4-bromo-2-methylpyridine (2.00 g) and diethyl carbonate (1.8 mL) in tetrahydrofuran (30 mL) cooled to −70° C. The solution was stirred for 1 h prior to the addition of another portion of lithium diisopropylamide (2 mol/L in tetrahydrofuran/heptane/ethylbenzene, 3.00 mL). Stirring was continued at −70° C. for one more hour and then the reaction was quenched by the addition of water. The resulting mixture was extracted with ethyl acetate and the combined extracts were washed with brine and dried (Na2SO4). The solvent was evaporated and the residue was chromatographed on silica gel (cyclohexane/ethyl acetate 95:5→1:1) to give the title compound. Yield: 2.35 g (83% of theory); LC (method 3): tR=2.86 min; Mass spectrum (ESI+): m/z=244/246 (Br) [M+H]+.

後処理

  1. stirringStirring
  2. customwas continued at −70° C. for one more hour
  3. customthe reaction was quenched by the addition of water
  4. extractionThe resulting mixture was extracted with ethyl acetate
  5. washthe combined extracts were washed with brine
  6. dry with materialdried (Na2SO4)
  7. customThe solvent was evaporated
  8. customthe residue was chromatographed on silica gel (cyclohexane/ethyl acetate 95:5→1:1)

出典と根拠

ORDレコード
ord-1e978b88f3a74dd893cce6fa67caea56
出典データセット
uspto-grants-2015_01
特許番号
US08933072B2

反応ノート

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