(E)-5-(3-bromophenyl)pent-4-enoic acid → 5-(3-bromophenyl)pentanoic Acid

Beteiligte Stoffe

Reaktionsschritte

J.1, (E)-5-(3-Bromophenyl)pent-4-enoic acid (4 g, 15.8 mmol) was dissolved in absolute ethanol (200 mL) and flushed with nitrogen before addition of 5% platinum sulfide on carbon (2.5 g). The solution was flushed with hydrogen at atmospheric pressure and stirred 5 h. The catalyst was removed by filtration over diatomaceous earth (Celite®) and the solvent immediately removed by rotory evaporation (in order to minimized esterification) to give J.2, 5-(3-bromophenyl)pentanoic acid 4 g (99%) which was carried forward without further purification. 1H NMR (500 MHz, CDCl3) 7.31-7.30 (m, 2H), 7.13 (t, J=7.6 Hz, 1H), 7.09-7.07 (d, J=7.6 Hz, 1H), 2.60 (t, J=7.0 Hz, 2H), 2.37 (t, J=7.0 Hz, 2H), 1.68-1.65 (m, 4H). LC (Cond.-J1): RT=2.1 min; LRMS: Anal. Calcd. for [M−H]− C11H13BrO2: 255.00; found: 254.99.

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