Bromocyclopentane → 3-Cyclopentyloxy-4-methoxybenzaldehyde

Beteiligte Stoffe

Reaktionsschritte

Cs2CO3 (214 g, 0.66 mol) was added to a mixture of 3-hydroxy-4-methoxybenzaldehyde (100 g, 0.66 mol) and cyclopentyl bromide (98 g, 0.66 mol) in anhydrous DMF (500 ml). The reaction mixture was stirred at RT for 16 h, then treated with a further portion of cyclopentyl bromide (98 g, 0.66 mol) and CS2CO3 (214 g, 0.66 mol). After a further 6h at RT, the mixture was filtered and concentrated in vacuo. The residue was dissolved in CH2Cl2 (300 ml) and washed with NaOH solution (10%, 2×150 ml). The organic layer was dried (MgSO4), concentrated in vacuo, and distilled (150° C., 10-2 mbar) to afford the title compound (130 g) as a viscous colorless oil. δH (CDCl3) 1.5-2.0 (8H, br m, CH2)4), 3.87 (3H, s, OCH3), 4.80 (1H, br m, OCHCH2), 6.90 (1H, d, J 8.7 Hz, ArH ortho to OMe), 7.30-7.45 (2H, m, 2×ArH meta to OMe), and 9.77 (1H, s, ArCHO).

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