p-Toluenesulfonic acid → HCID 22012686, Verbindung

A mixture of crude I in about 100 mL of methanol was treated with approximately 0.3 g of p-toluenesulfonic acid. After about 3 hours TLC analysis indicated almost no starting material remained. GC/MS analysis showed one long retention time component (>95%) MS (rel. intensity) 256 (0.5, M+), 255 (3), 226 (1), 134 (5), 133 (2), 105 (100), 91 (12), 77 (35), and 51 (20). This mixture was treated with about 5 mL of saturated NaHCO3, and the solvent was removed in vacuo. The residue was taken up in ether and purified through a short silica gel (hexane/ ether approximately 9:1) column to provide approximately 2.7 g of unstable 3,6-nonadiyn-1,8-diol, 8-benzoate. A mixture of approximately 1.25 g of this material in about 60 mL of ethanol containing approximately 0.32 g of quinoline and approximately 180 mg of lindlar catalyst was hydrogenated at atmospheric pressure until hydrogen uptake ceased. After about 2 hours, approximately 100 mg of additional catalyst was added and the reaction was continued until hydrogen uptake ceased (Mori, K, and Ebata, T., Tetrahedron, Volume 42, 3471,1986; herein incorporated by reference in its entirety). GC/MS analysis showed one major long retention time component: MS (rel. intensity) 260 (1, M+), 229 (1), 138 (15), 123 (2), 105 (100), 93 (18), 91 (15), 79 (45), and 77 (50). The product was isolated by filtration through celite and removal of the solvent in vacuo. The residue was taken up in ether, washed with dilute HCl, and brine, and dried over MgSO4. The infrared spectrum of a sample of this material isolated by preparative gas chromatography showed important absorptions at 3433 (br), 3053, 3012, 1712, 1602, 1580, 1450, 1268, 1108, 1043, and 709cm-1.