Tributylvinyltin → 3-Bromo-2-ethenylpyridine

HRID 860711Notes

Reaction equation

HRID 860711 reaction equation
Br[C:2]1[C:7]([Br:8])=[CH:6][CH:5]=[CH:4][N:3]=1.[CH2:9]([Sn](CCCC)(CCCC)C=C)[CH2:10]CC.[Li+].[Cl-]>CN(C=O)C.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>[Br:8][C:7]1[C:2]([CH:9]=[CH2:10])=[N:3][CH:4]=[CH:5][CH:6]=1

Participants

6

Reactant 3

HCID 81998TributylvinyltinHCID 433294Lithium ChlorideHCID 8171022,3-Dibromopyridine

Product 1

HCID 565907893-Bromo-2-ethenylpyridineYield 53.4%

Reagents, catalysts & solvents 2

HCID 178418476HCID 178418476, compoundCatalystHCID 6228DimethylformamideSolvent

Conditions

Temperature
100 °C

Procedure

A solution of 2,3-dibromopyridine (2.0 g, 8.44 mmol) in DMF (10 mL) was treated with tributyl(vinyl)tin (2.94 g, 9.29 mmol), LiCl (1.07 g, 25.32 mmol), and PdCl2(PPh3)2 (0.296 g, 0.422 mmol). The reaction mixture was heated at 100° C. for 18 hours. The mixture was extracted with hexanes (3×50 mL). The combined hexane layers were extracted with 1N HCl. The aqueous layer was neutralized with 1N NaOH, extracted with hexanes, and the extracts were dried (MgSO4), filtered, and concentrated to provide the desired product as a yellowish oil (0.83 g, 53% yield). MS m/z 184(MH+); 1H NMR (300 MHz, CD3OD) δ 5.53 (dd, J=10.80, 2.01 Hz, 1H), 6.33 (dd, J=16.83, 1.83 Hz, 1H), 7.08–7.26 (m, 2H), 7.96 (dd, J=8.05, 1.46 Hz, 1H), 8.44 (dd, J=4.76, 1.46 Hz, 1H); 13C NMR (300 MHz, CD3OD) δ 121.9, 122.4, 125.7, 134.9, 142.8, 149.5, 154.5.

Workup

  1. extractionThe mixture was extracted with hexanes (3×50 mL)
  2. extractionThe combined hexane layers were extracted with 1N HCl
  3. extractionextracted with hexanes
  4. dry with materialthe extracts were dried (MgSO4)
  5. filtrationfiltered
  6. concentrationconcentrated

Sources & evidence

ORD record
ord-e91475039af94f64ae5591a9845e553f
Source dataset
uspto-grants-2006_12
Patent number
US07153848B2

Reaction notes

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