Reaction Steps
CuCN (0.63 g, 7.06 mmol) is introduced into a round-bottomed flask placed under argon, THF (18 ml) is then added and the mixture is cooled to −78° C. n-Butyl-lithium (1.6M, 8.8 ml, 14.01 mmol) is then added dropwise and the mixture is allowed to return slowly to room temperature. The mixture is again cooled to −78° C. and n-Bu3SnH (3.8 ml, 14.01 mmol) is added, and the mixture is stirred for 10 minutes, during which the hydrogen is discharged. (2E)-Pent-2-en-4-yn-1-ol (0.50 g, 6.09 mmol) is then added and the reaction mixture is left stirring for 45 minutes before being poured into 200 ml of an NH4OH/NH4Cl (10/90) solution. Extraction is carried out with ether (3×100 ml), drying is carried out over Na2SO4 and evaporation is carried out under vacuum, in order to obtain, after silica chromatography, elution being carried out with a hexane/ethyl acetate/triethylamine (89/10/1) mixture, 1.52 g of the expected product (67%) in the form of an oil. 1H NMR (250.13 MHz, CDCl3) δ 0.8-1.1 (m, 15H, n-Bu), 1.2-1.4 (m, 6H, n-Bu), 1.4-1.6 (m, 6H, n-Bu), 4.20 (br s, 2H, 2H1), 5.79 (dt, J=15.6 and 5.8 Hz, 1H, H2), 6.21 (dd, J=15.6 and 10.0 Hz, 1H, H3), 6.26 (d, J=18.5 Hz, 2JSn-H=67.2 Hz, 1H, H5), 6.54 (dd, J=18.5 and 10.0 Hz, 3JSn-H=59.2 Hz, 1H, H4) ppm; 13C NMR (62.89 MHz, CDCl3) δ 9.6 (t, 1JSn-C=344.2/330.6 Hz, 3×), 13.8 (q, 3×), 27.4 (t, 2JSn-C=53.7 Hz, 3×), 29.3 (t, 3Sn-C=20.3 Hz, 3×), 63.5 (t, C1), 131.0 (d), 134.9 (d, 1JSn-C=315.4 Hz, C5), 135.4 (d), 146.2 (d) ppm; MS (EI+) m/e (relative intensity) 317 ([M-Bu+1]+, 100), 315 (75), 313 (42), 261 (48), 259 (37), 257 (21), 251 (31), 249 (23), 247 (16), 205 (56), 203 (47), 201 (29), 137 (64), 135 (49), 133 (29), 121 (36), 119 (28), 117 (16); HRMS (EI+) calc. for C17H35OSn 373.1704, found: 373.1693; FTIR (CHCl3) ν 3600-3200 (br, —OH), 2960 (s, C—H), 2925 (s, C—H), 2864 (s, C—H), 1579 (w, C═C), 1456 (m, C—O), 1006 (m) cm−1.
