2,2-dimethylhexanal

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

Procedure: To a solution containing 90 parts of acetylene dissolved in 600 parts by volume of tetrahydrofuran is added, over a period of about 50 minutes at -70°, 600 parts by volume of tetrahydrofuran containing 133 parts of ethyl magnesium bromide. Acetylene gas is continuously passed through the mixture during the addition period. Following that addition, the mixture is stirred at approximately -40° for about 45 minutes. To that mixture is then added, with stirring under nitrogen over a period of about 1 hour, 80 parts by volume of 2,2-dimethyl-n-hexaldehyde dissolved in 350 parts by volume of tetra=hydrofuran. Stirring at room temperature is continued for about 16 hours, at the end of which time approximately 125 parts by volume of saturated aqueous ammonium chloride is added slowly with stirring. The precipitate which forms is removed by filtration and the filtrate is partially concentrated, then diluted with ether and again filtered. The filtrate is stripped of solvent, then is distilled under reduced pressure to afford 4,4-dimethyl-1-octyn-3-ol, boiling at about 55°-65° at a pressure of about 3 mm. is added, over a period of about 50 minutes at -70° Following that addition To that mixture is then added with stirring under nitrogen over a period of about 1 hour Stirring at room temperature is added slowly with stirring The precipitate which forms is removed by filtration the filtrate is partially concentrated diluted with ether again filtered is distilled under reduced pressure

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

Procedure: The acetylenic alcohol intermediates are produced by reaction of the appropriate carbonyl compounds with an organometallic acetylene reagent, e.g. acetylene magnesium bromide. Typically, 2,2-dimethyl-n-hexaldehyde is contacted with acetylene magnesium bromide and the adduct hydrolyzed to afford 4,4-dimethyl-1-octyn-3-ol. The acetylenic alcohols in which the alcohol group is tertiary are obtained from the appropriate ketones. 2,2-Dimethyl-n-hexaldehyde, for example, is converted to 3,3-dimethyl-2-heptanone by reaction with methyl magnesium bromide followed by hydrolysis of the adduct and oxidation of the secondary alcohol group with chrominum trioxide. That ketone is then contacted with acetylene magnesium bromide and the adduct hydrolyzed to afford 3,4,4-trimethyl-1-octyn-3-ol.

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

Procedure: The acetylenic alcohol intermediates are produced by reaction of the appropriate carbonyl compounds with an organometallic acetylene reagent, e.g. acetylene magnesium bromide. Typically, 2,2-dimethyl-n-hexaldehyde is contacted with acetylene magnesium bromide and the adduct hydrolyzed to afford 4,4-dimethyl-1-octyn-3-ol. The acetylenic alcohols in which the alcohol group is tertiary are obtained from the appropriate ketones. 2,2-Dimethyl-n-hexaldehyde, for example, is converted to 3,3-dimethyl-2-heptanone by reaction with methyl magnesium bromide followed by hydrolysis of the adduct and oxidation of the secondary alcohol group with chrominum trioxide. That ketone is then contacted with acetylene magnesium bromide and the adduct hydrolyzed to afford 3,4,4-trimethyl-1-octyn-3-ol.