hept-5-yn-1-ol

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Oct-6-ynal was synthesized according to the synthetic scheme of J. Yan, J. Zhu, J. J. Matasi, J. W. Herndon, J. Org. Chem. 1990, 55, 786 with additional THP-protection during the methylation step. Commercially available hex-5-yn-1-ol (15.2 g, 155 mmol) was protected (DHP, PTSA, CH2Cl2, 0° C.→room temp., 5 h), and subsequently methylated (1.6M BuLi, MeI, THF, −78° C.→room temp., 12 h). Cleavage of the THP ether (PPTS, MeOH, room temp., 12 h) afforded hept-5-yn-1-ol (10.6 g, 61%), which was mesylated (MsCl, Et3N, Et2O, 0° C.→room temp., 12 h) and subsequently cyanated (KCN, DMF, reflux, 3.5 h) to provide oct-6-yne nitrile (7.90 g, 69%). Reduction of this nitrile (DIBAL-H, THF, 0° C.→room temp., 12 h) furnished oct-6-ynal (6.70 g, 83%).