2-Bromobenzaldehyde → HCID 19817970, compound

HRID 2352106Notes

Reaction equation

HRID 2352106 reaction equation
Br[C:2]1[CH:9]=[CH:8][CH:7]=[CH:6][C:3]=1[CH:4]=[O:5].[CH:10]1([CH2:16][CH2:17][CH2:18][CH2:19][CH2:20][CH2:21][C:22]#[CH:23])[CH2:15][CH2:14][CH2:13][CH2:12][CH2:11]1>C(N(CC)CC)C.[Pd](Cl)Cl.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1>[CH:10]1([CH2:16][CH2:17][CH2:18][CH2:19][CH2:20][CH2:21][C:22]#[C:23][C:2]2[CH:9]=[CH:8][CH:7]=[CH:6][C:3]=2[CH:4]=[O:5])[CH2:15][CH2:14][CH2:13][CH2:12][CH2:11]1

Participants

5

Reactant 2

HCID 811292-BromobenzaldehydeHCID 19817971HCID 19817971, compound

Product 1

HCID 19817970HCID 19817970, compound

Reagents, catalysts & solvents 2

HCID 6102075Dichlorobis(triphenylphosphine)palladiumCatalystHCID 8471TriethylamineSolvent

Procedure

To an ice cold solution of 1-hexyne (49.6 mmoles) in freshly distilled tetrahydrofuran (50 ml) containing a trace of triphenylmethane was added dropwise n-butyl lithium in hexane (49.5 mmoles). About 10 minutes after the addition was stopped, sieve dried hexamethylphosphoramide (57.5 mmoles) was added and the solution stirred for 10 minutes. A solution of 2-cyclohexylethyl bromide (51.3 mmoles) in tetrahydrofuran (10 ml) was added and the reaction mixture was stirred for about 3 hours as the temperature rose to room temperature. The mixture was taken up in ether (100 ml) and washed with water (3×100 ml) and sodium chloride solution (100 ml). The organic phase was dried over magnesium sulfate and evaporated to leave an oil which was purified by flash chromatography to give 1-cyclohexyloct-3-yne. This compound (20.8 mmoles) was treated with potassium hydride (36.8 mmoles) in propylene diamine to obtain the isomeric 8-cyclohexyloct-1-yne as an oil. A mixture of 2-bromobenzaldehyde (12.59 mmoles), 8-cyclohexyloct-1-yne (14.87 mmoles), cuprous iodide (0.17 mmoles) and bis(triphenylphosphine) palladium (II) chloride (0.26 mmoles) in triethylamine (35 ml) was refluxed under argon for 1.5 hours. The reaction mixture was cooled, filtered and the filtrate evaporated. The resulting residue was dissolved in ether (100 ml), washed with 3N hydrochloric acid (50 ml) and saturated sodium chloride solution (50 ml) and then dried over anhydrous magnesium sulfate and charcoal. The solution was evaporated to afford an oil which was purified by flash chromatography (2% ether/hexane) to yield 2-(8-cyclohexyl-1-octynyl)benzaldehyde as an oil. This benzaldehyde (10.22 mmoles) was hydrogenated with 10% palladium on charcoal in ethyl acetate to give the desired product as an oil, after chromatography (3% ether/hexane).

Workup

  1. temperaturewas refluxed under argon for 1.5 hours
  2. temperatureThe reaction mixture was cooled
  3. filtrationfiltered
  4. customthe filtrate evaporated
  5. dissolutionThe resulting residue was dissolved in ether (100 ml)
  6. washwashed with 3N hydrochloric acid (50 ml) and saturated sodium chloride solution (50 ml)
  7. dry with materialdried over anhydrous magnesium sulfate and charcoal
  8. customThe solution was evaporated
  9. customto afford an oil which
  10. customwas purified by flash chromatography (2% ether/hexane)

Sources & evidence

ORD record
ord-8d47839a893543b384211a837fd04aae
Source dataset
uspto-grants-1989_10
Patent number
US04874792

Reaction notes

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