Imidazole → 5-t-Butyldiphenylsilyloxy-4-(R)-iodopentanoic acid, methyl ester

HRID 2260881ノート

反応式

HRID 2260881 の反応式
[Si:1]([O:18][CH2:19][C@@H:20](O)[CH2:21][CH2:22][C:23]([O:25][CH3:26])=[O:24])([C:14]([CH3:17])([CH3:16])[CH3:15])([C:8]1[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.N1C=CN=C1.[I:52]I>C1(C)C=CC=CC=1>[Si:1]([O:18][CH2:19][C@H:20]([I:52])[CH2:21][CH2:22][C:23]([O:25][CH3:26])=[O:24])([C:14]([CH3:17])([CH3:16])[CH3:15])([C:8]1[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1

参加物

6

反応物 4

HCID 795ImidazoleHCID 807IodineHCID 11776TriphenylphosphineHCID 110254905-t-Butyldiphenylsilyloxy-4-(S)-hydroxypentanoic acid, methyl ester

生成物 1

HCID 151260955-t-Butyldiphenylsilyloxy-4-(R)-iodopentanoic acid, methyl ester

試薬・触媒・溶媒 1

HCID 1140Toluene溶媒

実験手順

To a solution of 7 (4.33 g, 11.2 mmol) in 250 mL toluene was added triphenylphosphine (5.9 g, 22.4 mmol), imidazole (2.3 g, 33.6 mmol), and iodine (4.26 g, 16.8 mmol) under a nitrogen atmosphere. The reaction mixture was lowered into a preheated heating mantle and refluxed for 1 hour. The reaction mixture was quenched by pouring into 200 mL saturated NaHCO3 solution. Excess triphenylphosphine was destroyed by the addition of iodine until an iodine coloration remained in the organic phase. The organic phase was then washed with 5% sodium thiosulfate solution (2×100 mL) and 2×200 mL water. The product was purified by flash chromatography with 6:1 hexane/ethyl acetate: yield 4.75 g (85%) of a viscous oil; [α]D25 +6.5° (C=1, CHCl3); FAB MS 497 (M+H)+, 439 (M-t-butyl)+ ; 1H NMR (CDCl3) δ 7.89 (m, 4, ArH), 7.4 (m, 6, ArH), 4.15 (m, 1, H-4), 3.85 (m, 2, CH2), 3.7 (s, 3, OCH3), 2.5 (m, 2, CH2), 2.25 (m, 1, H-2), 2.1 (m, 1, H-2), 1.1 (s, 9, t-butyl).

後処理

  1. temperaturerefluxed for 1 hour
  2. customThe reaction mixture was quenched
  3. additionby pouring into 200 mL saturated NaHCO3 solution
  4. customExcess triphenylphosphine was destroyed by the addition of iodine until an iodine coloration
  5. washThe organic phase was then washed with 5% sodium thiosulfate solution (2×100 mL) and 2×200 mL water
  6. customThe product was purified by flash chromatography with 6:1 hexane/ethyl acetate

出典と根拠

ORDレコード
ord-abfa6f9e681a4dc8865f377c4150ba58
出典データセット
uspto-grants-1995_12
特許番号
US05478928

反応ノート

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