Tributylvinyltin → Methyl 3-ethenylpyridine-2-carboxylate

HRID 68287Notes

Reaction equation

HRID 68287 reaction equation
FC(F)(F)S(O[C:7]1[C:8]([C:13]([O:15][CH3:16])=[O:14])=[N:9][CH:10]=[CH:11][CH:12]=1)(=O)=O.[Li+].[Cl-].[CH2:21]([Sn](CCCC)(CCCC)C=C)[CH2:22]CC>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>[CH:21]([C:7]1[C:8]([C:13]([O:15][CH3:16])=[O:14])=[N:9][CH:10]=[CH:11][CH:12]=1)=[CH2:22]

Participants

6

Reactant 3

HCID 81998TributylvinyltinHCID 433294Lithium ChlorideHCID 11066008Methyl 3-(trifluoromethylsulfonyloxy)-pyridine-2-carboxylate

Product 1

HCID 15257081Methyl 3-ethenylpyridine-2-carboxylate

Reagents, catalysts & solvents 2

HCID 178418476HCID 178418476, compoundCatalystHCID 6228DimethylformamideSolvent

Conditions

Temperature
100 °C

Procedure

To a solution of methyl 3-(trifluoromethylsulfonyloxy)picolinate (i.e. Cap 173, step a) (570 mg, 2.0 mmol), an intermediate in the preparation of Cap-174, in DMF (20 mL) was added LiCl (254 mg, 6.0 mmol), tributyl(vinyl)stannane (761 mg, 2.4 mmol) and bis(triphenylphosphine)palladium dichloride (42 mg, 0.06 mmol). The mixture was heated at 100° C. for 4 h before the solvent was removed in vacuo. The residue was taken up in acetonitrile (50 mL) and hexanes (50 mL) and the resulting mixture was washed twice with hexanes. The acetonitrile layer was then separated, filtered through Celite, and evaporated. Purification of the residue by flash chromatography on a Horizon instrument (gradient elution with 25% ethyl acetate in hexanes to 65% ethyl acetate in hexanes) afforded methyl 3-vinylpicolinate (i.e. Cap-175, step a) (130 mg, 40%) as a yellow oil. 1H NMR (300 MHz, CDCl3) δ ppm 8.60 (1H, dd, J=4.6, 1.7 Hz), 7.94 (1H, d, J=7.7 Hz), 7.33-7.51 (2H, m), 5.72 (1H, d, J=17.2 Hz), 5.47 (1H, d, J=11.0 Hz), 3.99 (3H, s). Rt=1.29 min (Cond.-MD1); LC/MS: Anal. Calcd. for [M+H]+ C9H10NO2: 164.07. found: 164.06.

Workup

  1. customan intermediate in the preparation of Cap-174
  2. customwas removed in vacuo
  3. washhexanes (50 mL) and the resulting mixture was washed twice with hexanes
  4. customThe acetonitrile layer was then separated
  5. filtrationfiltered through Celite
  6. customevaporated
  7. customPurification of the residue by flash chromatography
  8. washon a Horizon instrument (gradient elution with 25% ethyl acetate in hexanes to 65% ethyl acetate in hexanes)

Sources & evidence

ORD record
ord-539fa9dc7fb64483aa2e213b49e8c4cd
Source dataset
uspto-grants-2014_09
Patent number
US08822444B2

Reaction notes

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