Reaction Steps
4-Methylbenzenesulfonyl chloride (5.7 g, 30 mmol), 3-hexyn-1-ol (1.5 mL, 20 mmol) and pyridine (3.2 mL, 40 mmol) in CH2Cl2 (20 mL) were treated according to Procedure 4 giving hex-3-ynyl 4-methylbenzenesulfonate (3.8 g, 75%) as a colourless oil. Vanillin (0.76 g, 5.0 mmol) was alkylated with hex-3-ynyl 4-methylbenzenesulfonate (1.9 g, 7.5 mmol) according to Procedure 4 and the crude product was recrystallised from EtOAc/petrol to provide 4-(hex-3-ynyloxy)-3-methoxybenzaldehyde (0.45 g, 39%) as a colourless crystalline solid; mp 80-81° C.; δH (400 MHz, CDCl3) 1.12 (t, J=7.6 Hz, 3H, CH3), 2.17 (tq, J=7.6, 2.4 Hz, 2H, CH3CH2), 2.73 (tt, J=7.6, 2.4 Hz, 2H, OCH2CH2C), 3.92 (s, 3H, OCH3), 4.19 (t, J=7.6 Hz, 2H, OCH2), 7.00 (d, J5,6=8.0 Hz, 1H, H5), 7.41 (d, J2,6=1.6 Hz, 1H, H2), 7.44 (dd, J5,6=8.0, J2,6=1.6 Hz, 1H, H6), 9.85 (s, 1H, CHO); δC (100 MHz, CDCl3) 12.4, 14.0, 19.5, 56.0, 67.6, 74.3, 84.0, 109.5, 111.8, 126.6, 130.3, 149.9, 153.5, 190.8; vmax 1023, 1134, 1263, 1586, 1680, 2877, 2972 cm−1.
