Potassium Carbonate → tert-butyl 4-(2-bromo-5-(trifluoromethyl)phenyl)-5,6-dihydropyridine-1(2H)-carboxylate

HRID 2172287Notes

Reaction equation

HRID 2172287 reaction equation
[Br:1][C:2]1[CH:7]=[CH:6][C:5]([C:8]([F:11])([F:10])[F:9])=[CH:4][C:3]=1I.CC1(C)C(C)(C)OB([C:21]2[CH2:26][CH2:25][N:24]([C:27]([O:29][C:30]([CH3:33])([CH3:32])[CH3:31])=[O:28])[CH2:23][CH:22]=2)O1.C(=O)([O-])[O-].[K+].[K+]>O1CCOCC1.O.C(OCC)(=O)C.C1C=CC(P(C2C=CC=CC=2)[C-]2C=CC=C2)=CC=1.C1C=CC(P(C2C=CC=CC=2)[C-]2C=CC=C2)=CC=1.Cl[Pd]Cl.[Fe+2].C(Cl)Cl>[Br:1][C:2]1[CH:7]=[CH:6][C:5]([C:8]([F:11])([F:10])[F:9])=[CH:4][C:3]=1[C:21]1[CH2:26][CH2:25][N:24]([C:27]([O:29][C:30]([CH3:33])([CH3:32])[CH3:31])=[O:28])[CH2:23][CH:22]=1

Participants

8

Procedure

A solution of 1-bromo-2-iodo-4-(trifluoromethyl)benzene (1.408 ml, 8.55 mmol), tert-butyl 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-5,6-dihydropyridine-1(2H)-carboxylate (Frontier Scientific, Logan, Utah, 2.78 g, 8.98 mmol), Pd(dppf)Cl2—CH2Cl2 adduct (Strem Chemicals Inc., Newburyport, Mass., 0.349 g, 0.427 mmol), and potassium carbonate (2.052 g, 34.2 mmol) in dioxane (32.1 ml) and water (10.69 ml) was stirred at 70° C. for three hours. (LC-MS MH+ 430.1) The reaction was diluted with ethyl acetate and washed with water. The aqueous layer was extracted with ethyl acetate, and the combined organic layers were dried with sodium sulfate, filtered, and concentrated. The material was purified via column chromatography (silica gel 80 g, gradient elution 0 to 100% Et2O:Heptane) to afford tert-butyl 4-(2-bromo-5-(trifluoromethyl)phenyl)-5,6-dihydropyridine-1(2H)-carboxylate (2.54 g, 6.25 mmol) as a light yellow oil. [M+H]+=428.0. 1H NMR (400 MHz, CHLOROFORM-d) δ ppm=7.69 (d, J=8.3 Hz, 1H), 7.43 (d, J=2.2 Hz, 1H), 7.41-7.36 (m, 1H), 5.69 (br. s., 1H), 4.08 (q, J=2.7 Hz, 2H), 3.66 (t, J=5.6 Hz, 2H), 2.48-2.40 (m, 2H), 1.52 (s, 9H)

Workup

  1. washwashed with water
  2. extractionThe aqueous layer was extracted with ethyl acetate
  3. dry with materialthe combined organic layers were dried with sodium sulfate
  4. filtrationfiltered
  5. concentrationconcentrated
  6. customThe material was purified via column chromatography (silica gel 80 g, gradient elution 0 to 100% Et2O:Heptane)

Sources & evidence

ORD record
ord-a1332cb5926143df9a30b096116d0319
Source dataset
uspto-grants-2015_06
Patent number
US09051311B2

Reaction notes

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