Phosphorus tribromide → 3,5-Dimethoxybenzyl Bromide

HRID 41134

反応式

HRID 41134 の反応式
P(Br)(Br)[Br:2].[CH3:5][O:6][C:7]1[CH:8]=[C:9]([CH:12]=[C:13]([O:15][CH3:16])[CH:14]=1)[CH2:10]O>C1COCC1>[CH3:5][O:6][C:7]1[CH:8]=[C:9]([CH:12]=[C:13]([O:15][CH3:16])[CH:14]=1)[CH2:10][Br:2]

参加物

4

反応物 2

HCID 24614Phosphorus tribromideHCID 697183,5-Dimethoxybenzyl alcohol

生成物 1

HCID 12744903,5-Dimethoxybenzyl Bromide収率 92%

試薬・触媒・溶媒 1

HCID 8028Tetrahydrofuran溶媒

実験手順

Phosphorus tribromide (0.4 eq) was added to the alcohol 304 (25 g, 0.13 mol) in THF (100 mL) very slowly at −10° C. and the mixture which resulted was stirred for 15-30 min at the same temperature. By this time all the starting material had disappeared (TLC). The reaction mixture was quenched by addition of ice-cold H2O (100 mL) and then filtered through a Buchner funnel. The filtrate was diluted with brine (100 mL) and extracted with EtOAc (3×300 mL). The combined organic extracts were dried (Na2SO4) and concentrated in vacuo. The crude oil was purified by FCC (20% ethylacetate in hexane) to afford the bromide 305 as a white solid (92%)a: 1H NMR (500 MHz, CDCl3) δ 6.61 (2H, d, J=2.3 Hz), 6.46 (1H, t, J=2.3 Hz), 4.5 (2H, s), 3.85 (6H, s). 13C NMR (125 MHz, CDCl3): δ 161.3, 140.2, 107.4, 101.0, 55.8, 34.1. The spectral data for 305 were in excellent accord with data previously reported on it (Seidel et al., 1990)1. This material was employed directly in the next step.

後処理

  1. customthe mixture which resulted
  2. customThe reaction mixture was quenched by addition of ice-cold H2O (100 mL)
  3. filtrationfiltered through a Buchner funnel
  4. additionThe filtrate was diluted with brine (100 mL)
  5. extractionextracted with EtOAc (3×300 mL)
  6. dry with materialThe combined organic extracts were dried (Na2SO4)
  7. concentrationconcentrated in vacuo
  8. customThe crude oil was purified by FCC (20% ethylacetate in hexane)

出典と根拠

ORDレコード
ord-984ac72a3a6a4f0299bfd004c79eac98
出典データセット
uspto-grants-2013_09
特許番号
US08530512B2

関連ノート

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