Reaction #55952

Reaction equation

3,7,11-trimethyl-7,10-dodecadien-1-yn-3-ol

→

2,6,10,15,19,23-hexamethyl-2,6,11,18,22-tetracosapentaen-13-yn-10,15-diol

Yield 94.0%

Solvents

benzene

Conditions

Workup

1. 1
   ConcentrationThe reaction mixture was concentrated
2. 2
   Otherpurified by column chromatography (developer system: benzene-chloroform =1:1)
3. 3
   Otherhad substantially reacted

Procedure

In contact with triphenylphosphine rhodium chloride [RhCl (PPh3)3 ] catalyst, 3,7,11-trimethyl-7,10-dodecadien-1-yn-3-ol was refluxed in benzene for 3 hours. The reaction mixture was concentrated and purified by column chromatography (developer system: benzene-chloroform =1:1). Analysis of the product by gel permeation chromatography showed that the starting material had substantially reacted to yield 2,6,10,15,19,23-hexamethyl-2,6,11,18,22-tetracosapentaen-13-yn-10,15-diol (94% selectivity). The resulting acetylenic diol was hydrogenated in n-hexane and in contact with 5% palladium-on-carbon at room temperature and elevated pressure of 80-100 kg/cm2 to yield 2,6,10,15,19,23-hexamethyltetracosa-10,15-diol (bp. 218-220° C. / 0.2 mm Hg). This product was subjected to hydrogenolysis in acetic acid in contact with palladium-on-carbon at a hydrogen pressure of 100 kg/cm2 and at a reaction temperature of 170-190° C. The resultant compound was analyzed by gas chromatography and nuclear magnetic resonance spectroscopy and the data comformed with a standard sample of squalane.

Source