Reaktion #9056

ord-dab199994697470a9010da92e0d118eb

Lösungsmittel

Reaktionsbedingungen

Detaillierte Bedingungen
See reaction.notes.procedure_details.

Aufarbeitung

  1. 1
    Temperaturat reflux for 18 h after which it
  2. 2
    Filtrationwas filtered
  3. 3
    Einengenconcentrated to a yellow/orange syrup and crystals (1.4 g)
  4. 4
    SonstigePurification by column chromatography on silica gel (200:15—Hexanes:EtOAc)

Vorschrift

To a stirred solution of 4-methyl-benzimidazole-1-carboxylic acid tert-butyl ester (800 mg, 3.4 mmol) in CCl4 (7 mL) was added N-bromosuccinimide (730 mg, 4.1 mmol) and 2,2′-azobis(2-methylpropionitrile) (84 mg, 0.51 mmol). The resultant mixture was heated at reflux for 18 h after which it was filtered and concentrated to a yellow/orange syrup and crystals (1.4 g). Purification by column chromatography on silica gel (200:15—Hexanes:EtOAc) gave the desired title compound as a yellow syrup (635 mg, 60%). 1H NMR (300 MHz, CDCl3) δ 8.48 (s, 1H), 7.95 (dd, 1H, J=7.8, 1.5 Hz), 7.42–7.34 (m, 2H), 4.96 (s, 2H), 1.71 (s, 9H).

Quelle

DOI: 10.6084/m9.figshare.5104873.v1Patent: US07091217B2uspto-grants-2006_08