反应详情

(-)-(10R)-3,3,8,8,10-Pentamethyl-1,5-dioxaspiro[5,5]undecan-9-one (1.31 g, 5.5 mmol) was reacted with Z-3-methylpent-2-en-4-yn-1-ol (0.65 g, 6.7 mmol) and n-butyllithium (1.6M in hexane, 8 mL, 12.8 mmol) in dry THF. The crude product obtained (yellow oil, 2.6 g) was purified by flash column chromatography (75% ether+25% hexane) followed by distillation using the Kugel-rohr apparatus (about 250° C., 0.06 mm Hg) to give the product as a colorless oil (1.40 g, 77%), [a]D +30.0° C. (c 1.05, CH3OH); ir and 1H nmr identical to those reported above for its antipode.

1. customThe crude product obtained (yellow oil, 2.6 g)
2. customwas purified by flash column chromatography (75% ether+25% hexane)
3. distillationfollowed by distillation
4. customthe Kugel-rohr apparatus (about 250° C., 0.06 mm Hg)