Ethyl Acetate → Ethyl 6-bromo-8-phenylimidazo[1,2-a]pyridine-2-carboxylate

HRID 2197549ノート

反応式

HRID 2197549 の反応式
Br.[Br:2][C:3]1[CH:4]=[C:5](Br)[C:6]2[N:7]([CH:9]=[C:10]([C:12]([O:14][CH2:15][CH3:16])=[O:13])[N:11]=2)[CH:8]=1.[C:18]1(B(O)O)[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=1.[O-]P([O-])([O-])=O.[K+].[K+].[K+].C(OCC)(=O)C>C1(C)C=CC=CC=1.C(O)C.C1C=CC([P]([Pd]([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)[P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1>[Br:2][C:3]1[CH:4]=[C:5]([C:18]2[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=2)[C:6]2[N:7]([CH:9]=[C:10]([C:12]([O:14][CH2:15][CH3:16])=[O:13])[N:11]=2)[CH:8]=1

参加物

8

反応条件

温度
80 °C

実験手順

A solution of ethyl 6,8-dibromoimidazo[1,2-a]pyridine-2-carboxylate hydrobromide (0.5 g, 1.2 mmol) and phenylboronic acid (0.15 g, 1.2 mmol) in toluene (10 mL) and ethanol (2 mL) was bubbled nitrogen for 20 mins. The mixture was then treated with Pd(PPh3)4 (30 mg, 0.026 mmol) and K3PO4 (2 M, 1 mL, 2 mmol) and heated at 80° C. overnight. The reaction was cooled, poured into ethyl acetate (200 mL), washed with brine, separated, and concentrated. The residue was purified by column chromatography on silica gel using ethyl acetate in hexanes (10%) as eluent. The product containing fractions were concentrated to give 0.23 g (58% yield) of ethyl 6-bromo-8-phenylimidazo[1,2-a]pyridine-2-carboxylate as a white solid. LCMS (Conditions C): 3.41 min (RT); (M+H)+=347.24 (100%), 345.24 (100%). 1H NMR, 400 MHz, CDCl3: δ 8.27 (d, J=1.6 Hz, 1 H), 8.19 (s, 1 H), 8.02 (m, 2H), 7.52-7.41 (m, 4 H), 4.45 (q, J=7.1 Hz, 2 H), 1.42 (t, J=7.0 Hz, 3 H).

後処理

  1. temperatureThe reaction was cooled
  2. washwashed with brine
  3. customseparated
  4. concentrationconcentrated
  5. customThe residue was purified by column chromatography on silica gel
  6. additionThe product containing fractions
  7. concentrationwere concentrated

出典と根拠

ORDレコード
ord-ebd32fbdf3544415a280a002fe94b32d
出典データセット
uspto-grants-2012_12
特許番号
US08338604B2

反応ノート

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