2-undec-10-ynoxyoxane

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

Procedure: 5 g (0.0198 mol) of 11-tetrahydropyranyloxyundecyne of Example 7 were placed in a mixture of 50 ml of THF and 25 ml of hexamethylphosphoric triamide under an argon atmosphere. At -60° C., 12.4 ml (0.0198 mol) of n-butyllithium in hexane were added dropwise. After 30 min at -60° C., a solution of 9.0 g (0.0248 mol) of 1-bromoeicosane in 25 ml of THF was added dropwise at -60° C. The mixture was left to warm up to room temperature. After 18 h at room temperature, it was poured into 25% aqueous NaH2PO4 solution and extracted with n-heptane (3×). The combined organic phases were dried (Na2SO4) and the solvent was removed. Flash chromatography on silica gel (n-heptane/ethyl acetate =15:1) gave 6.5 g (61.3% of theory) of 1-tetrahydropyranyloxy-hentriacont-10-yne. The mixture was left After 18 h at room temperature extracted with n-heptane (3×) The combined organic phases were dried (Na2SO4) the solvent was removed

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

Procedure: 17.5 g (0,104 mol) of undec-10-yn-1-ol were dissolved in 100 ml of dichloromethane and 25 ml of dihydropyran, and a catalytic amount (spatula tipful) of p-toluenesulfonic acid monohydrate was added. The reaction mixture was left to stand overnight at room temperature and poured into saturated aqueous sodium chloride solution. Extraction with dichloromethane (3×), drying (Na2SO4) of the combined organic phases and flash chromatography on silica gel (n-heptane/ethyl acetate=10:1) gave 24 g (92% of theory) of 11-tetrahydropyranyloxyundecyne. The reaction mixture was left Extraction with dichloromethane (3×) drying (Na2SO4) of the combined organic phases and flash chromatography on silica gel (n-heptane/ethyl acetate=10:1)