Hydrochloric Acid → 2-Ethynyl-6-methylpyridine

HRID 8214

Reaction equation

HRID 8214 reaction equation
Br[C:2]1[CH:7]=[CH:6][CH:5]=[C:4]([CH3:8])[N:3]=1.C[Si]([C:13]#[CH:14])(C)C.[OH-].[Na+].Cl>C(N(CC)CC)C.CO.[Cu]I.Cl[Pd](Cl)([P](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1)[P](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1>[C:13]([C:2]1[CH:7]=[CH:6][CH:5]=[C:4]([CH3:8])[N:3]=1)#[CH:14]

Participants

9

Reactant 4

HCID 313Hydrochloric AcidHCID 14798Sodium HydroxideHCID 66111TrimethylsilylacetyleneHCID 792052-Bromo-6-methylpyridine

Product 1

HCID 134006352-Ethynyl-6-methylpyridineYield 341.4%

Reagents, catalysts & solvents 4

HCID 24350Copper(1+) iodide; Copper(I) iodide; Cuprous iodide; Cuprous iodide (CuI)CatalystHCID 178418476HCID 178418476, compoundCatalystHCID 887MethanolSolventHCID 8471TriethylamineSolvent

Procedure

A solution of 2-bromo-6-methylpyridine (0.5 g, 2.9 mmol) and (trimethylsilyl)acetylene (0.29 g, 2.9 mmol) in triethylamine (15 mL) is purged with argon. Copper(I) iodide (11 mg, 0.06 mmol) and (PPh3)2PdCl2 (42 mg, 0.06 mmol) are added and the reaction is stirred under argon at room temperature for 2 h. The solvent is removed in vacuo and the residue is diluted in ethyl acetate (50 mL) and water (50 mL). The organic is separated and washed with brine. The solvent is removed to afford a dark oil. This oil is diluted in methanol (50 mL) and treated with a 1 N sodium hydroxide solution (10 mL) and stirred for 3 h at room temperature. The aqueous is neutralized with 1 N hydrochloric acid and extracted with ethyl acetate. The solvent is removed in vacuo to afford a dark oil that is purified by SiO2 column chromatography to yield 1.16 g (24%) of the title compound as a light yellow oil.

Workup

  1. customThe solvent is removed in vacuo
  2. additionthe residue is diluted in ethyl acetate (50 mL)
  3. customThe organic is separated
  4. washwashed with brine
  5. customThe solvent is removed
  6. customto afford a dark oil
  7. stirringstirred for 3 h at room temperature
  8. extractionextracted with ethyl acetate
  9. customThe solvent is removed in vacuo
  10. customto afford a dark oil that
  11. customis purified by SiO2 column chromatography

Sources & evidence

ORD record
ord-24f8476f7c90486db479cc7ee0b431c1
Source dataset
uspto-grants-2006_08
Patent number
US07087626B2

Linked notes

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