Triethylamine → 6,6-Dimethoxyhex-1-ene

Participants

Reaction Steps

The crude product containing compound 5 was taken up in 30 mL of MeOH, and camphorsulfonic acid (596 mg, 2.5 mmol) and trimethyl orthoformate (5.46 mL, 50 mmol) were added. The mixture was heated at reflux for 3 h, then allowed to stand at room temperature overnight. The acid was neutralized by the addition of 0.70 mL of triethylamine, and most of the solvent was removed by distillation. The residue was partitioned between water and hexane, the hexane layer was dried over anhydrous Na2SO4, and the solution was filtered through a 3 in column of silica gel, eluting with additional hexane. The solvent was removed by distillation to leave 5.0 g of the product, compound 6, as a colorless liquid. 1H NMR (CDCl3) δ 1.39-1.49 (m, 2), 1.58-1.65 (m, 2), 2.03-2.11 (m, 2), 3.31 (s, 6, CH(OCH3)2), 4.37 (t, 1, J=5.7CH(OCH3)2), 4.93-5.05 (m, 2, CH═CH2), 5.80 (dddd, 1, J=6.6, 6.6, 10.3, 16.9, CH═CH2); 13C NMR (CDCl3) δ 23.79, 31.83, 33.42, 52.49, 104.33, 114.64, 138.38.

Provenance & Evidence