1-Pentol → 9-(5-Hydroxy-3-methylpent-3-en-1-ynyl)-3,3,8,8,10-pentamethyl-1,5-dioxaspiro[5,5]undecan-9-ol

HRID 1589995Notes

Reaction equation

HRID 1589995 reaction equation
[CH3:1][C:2]1([CH3:17])[CH2:7][O:6][C:5]2([CH2:12][C@@H:11]([CH3:13])[C:10](=[O:14])[C:9]([CH3:16])([CH3:15])[CH2:8]2)[O:4][CH2:3]1.[CH3:18]/[C:19](/[C:23]#[CH:24])=[CH:20]/[CH2:21][OH:22].C([Li])CCC>C1COCC1>[OH:22][CH2:21][CH:20]=[C:19]([CH3:18])[C:23]#[C:24][C:10]1([OH:14])[CH:11]([CH3:13])[CH2:12][C:5]2([O:4][CH2:3][C:2]([CH3:1])([CH3:17])[CH2:7][O:6]2)[CH2:8][C:9]1([CH3:16])[CH3:15]

Participants

5

Reactant 3

HCID 64358221-PentolHCID 14702805(-)-(10R)-3,3,8,8,10-Pentamethyl-1,5-dioxaspiro[5,5]undecan-9-oneHCID 178418339Butyllithium

Product 1

HCID 537533279-(5-Hydroxy-3-methylpent-3-en-1-ynyl)-3,3,8,8,10-pentamethyl-1,5-dioxaspiro[5,5]undecan-9-olYield 77%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

(-)-(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.

Workup

  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)

Sources & evidence

ORD record
ord-946cac157a284b51b70fc3f904f56bba
Source dataset
uspto-grants-1993_04
Patent number
US05201931

Reaction notes

Loading…