反応 #155469

反応方程式

methyl 3-(trifluoromethylsulfonyloxy)picolinate

LiCl

tributyl(vinyl)stannane

→

methyl 3-vinylpicolinate

溶媒

DMF

反応条件

後処理

1. 1
   その他an intermediate in the preparation of Cap-174
2. 2
   その他was removed in vacuo
3. 3
   洗浄hexanes (50 mL) and the resulting mixture was washed twice with hexanes
4. 4
   その他The acetonitrile layer was then separated
5. 5
   ろ過filtered through Celite
6. 6
   その他evaporated
7. 7
   その他Purification of the residue by flash chromatography
8. 8
   洗浄on a Horizon instrument (gradient elution with 25% ethyl acetate in hexanes to 65% ethyl acetate in hexanes)

実験手順

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.

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