Triethylamine → 2-Bromo-5-(2-(trimethylsilyl)ethynyl)pyridine

HRID 629217Notes

Reaction equation

HRID 629217 reaction equation
[Br:1][C:2]1[CH:7]=[CH:6][C:5](I)=[CH:4][N:3]=1.[C:9]([Si:11]([CH3:14])([CH3:13])[CH3:12])#[CH:10].C(N(CC)CC)C>C1COCC1.C1C=CC(P(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1.C1C=CC(P(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1.Cl[Pd]Cl.[Cu]I>[Br:1][C:2]1[CH:7]=[CH:6][C:5]([C:10]#[C:9][Si:11]([CH3:14])([CH3:13])[CH3:12])=[CH:4][N:3]=1

Participants

7

Reactant 3

HCID 8471TriethylamineHCID 66111TrimethylsilylacetyleneHCID 47382712-Bromo-5-iodopyridine

Product 1

HCID 129830922-Bromo-5-(2-(trimethylsilyl)ethynyl)pyridineYield 87.5%

Reagents, catalysts & solvents 3

HCID 24350Copper(1+) iodide; Copper(I) iodide; Cuprous iodide; Cuprous iodide (CuI)CatalystHCID 6102075Dichlorobis(triphenylphosphine)palladiumCatalystHCID 8028TetrahydrofuranSolvent

Conditions

Temperature
50 °C

Procedure

2-Bromo-5-iodopyridine (2.5 g, 8.8 mmol) was dissolved under nitrogen in 50 ml THF. Bis-(triphenylphosphine)-palladium(II)dichloride (618 mg, 880 μmol, 0.1 equiv.), ethynyltrimethylsilane (950 mg, 1.34 ml, 9.6 mmol, 1.1 equiv.), triethylamine (1.78 g, 2.44 ml, 17.6 mmol, 3 equiv.) and copper(I)iodide (84 mg, 440 μmol, 0.05 equiv.) were added and the mixture was stirred for 3 hours at 50° C. The reaction mixture was cooled and evaporated to dryness. The crude product was purified by flash chromatography on silica gel, eluting with an ethyl acetate:heptane gradient 0:100 to 15:85. The desired 2-bromo-5-trimethylsilanylethynyl-pyridine (1.95 g, 7.7 mmol, 87% yield) was obtained as a white solid, MS: m/e=254.1/256.1 (M+H+).

Workup

  1. temperatureThe reaction mixture was cooled
  2. customevaporated to dryness
  3. customThe crude product was purified by flash chromatography on silica gel
  4. washeluting with an ethyl acetate

Sources & evidence

ORD record
ord-ed1cb975324a478a890d7a8f078d4571
Source dataset
uspto-grants-2016_04
Patent number
US09315498B2

Reaction notes

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