1-(Pyridin-3-yl)but-2-yn-1,4-diol

The general part of the experimental section [1] has been presented elsewhere. ⁿBuLi (1.6 M) (6.8 mL, 10.8 mmol) was added to a solution of propargyl alcohol 1 (0.35 mL, 4.9 mmol) in THF (10 mL) under nitrogen at 20°C and the mixture stirred for 10 min. The reaction was then cooled to -78°C and a solution of pyridine-3-carboxaldehyde 2 (500 mg, 4.9 mmol) in THF (1 mL) was added dropwise. The resultant mixture was stirred for 1 h at -78°C, warmed to 0°C then stirred for 1 h. Saturated aqueous ammonium chloride (15 mL) was added and then the mixture was warmed to room temperature. The orange-yellow solution was extracted with diethyl ether (3 x 20 mL), dried over magnesium sulfate and concentrated under reduced pressure to afford a yellow oil. Further purification by flash chromatography using ethyl acetate as eluent gave the title compound 3 (195 mg, 27%) as a pale yellow oil.

IR (neat): 3368b, 2957s, 2932s, 2860s, 2235w, 1581w, 1466m, 1427m.

¹H NMR (200 MHz, CDCl₃): 4.34 (2H, d, J 1.6 Hz, H4), 5.56 (1H, br. s, H1), 7.25-7.33 (1H, m, H5'), 7.88 (1H, d, J_4',5' 8.1 Hz, H4'), 8.51 (1H, d, J_5',6' 4.0 Hz, H6'), 8.78 (1H, s, H2').

¹³C NMR (50 MHz, CDCl₃): 50.5 (CH₂, C4), 62.0 (CH, C1), 84.3 (quat., C3), 85.8 (quat., C2), 123.6 (CH, C5'), 135.0 (CH, C4'), 136.9 (CH, C6'), 147.8 (CH, C3'), 148.7 (CH, C2').

EI-MS: 163 (M⁺, 96%), 146 (68%), 132 (51%), 117 (77%), 106 (42%), 80 (100%).

Anal. Calc. For C₁₅H₉NO₂, 163.06333; found M⁺, 163.06309.