Sodium Hydroxide → 2,7-Diethynylnaphthalene

Participants

Reaction Steps

2,7-bis((Trimethylsilyl)ethynyl)naphthalene 2 (0.45 g, 1.39 mmol) was dissolved in THF (80 ml) and aqueous 1M NaOH solution (80 ml) and the mixture stirred for two hours at room temperature. The reaction was extracted with DCM (3×250 ml), dried (MgSO4) and taken to dryness in vacuo. The pale yellow crude solid obtained was purified by flash column chromatography (hexane), to give 2,7-diethynylnaphthalene 3 (0.24 g, quantitative) as an off white solid; Rf 0.56 [5% EtOAc in hexane]; mp: 124-126° C.; δH (CDCl3, 400 MHz) 7.97 (2H, s, 2×ArH), 7.76 (2H, d, J=8.8 Hz, 2×ArH), 7.54 (2H, dd, J1=8.4 Hz, J2=1.6 Hz, 2×ArH), 3.17 (2×HC≡C); δC (CDCl3, 100 MHz) 132.57 (Ar—C), 132.30 (Ar—C), 132.00 (2×Ar—CH), 129.58 (2×Ar—CH), 127.90 (2×Ar—CH), 120.33 (2×Ar—C), 83.57 (2×C≡C), 77.99 (2×HC≡C); HRMS m/z calc. C14H8 [M]+176.0620. found [M+H]+176.0625; anal. CHN calcd. C14H8 C, 95.4%; H, 4.6%. found C, 95.3%; H, 4.3%.

Provenance & Evidence