tert-Butyl 3-(((trifluoromethyl)sulfonyl)oxy)-5,6-dihydropyridine-1(2H)-carboxylate → tert-butyl 5-(1,3-thiazol-2-yl)-3,6-dihydropyridine-1(2H)-carboxylate

HRID 490220Notes

Reaction equation

[Br-].[S:2]1[CH:6]=[CH:5][N:4]=[C:3]1[Zn+].FC(F)(F)S(O[C:14]1[CH2:19][N:18]([C:20]([O:22][C:23]([CH3:26])([CH3:25])[CH3:24])=[O:21])[CH2:17][CH2:16][CH:15]=1)(=O)=O>O1CCCC1>[S:2]1[CH:6]=[CH:5][N:4]=[C:3]1[C:16]1[CH2:17][N:18]([C:20]([O:22][C:23]([CH3:26])([CH3:25])[CH3:24])=[O:21])[CH2:19][CH2:14][CH:15]=1

Participants

Conditions

Temperature: 50 °C

Procedure

To the mixture of 2-thiazolylzinc bromide (20 mL, 10 mmol) in dry tetrahydrofuran (30 mL) at 0° C. was added the product from Example 328B (3.3 gm, 10 mmol) and tetrakis(tripehynlphosphine) palladium (0) (10% mole 1.1 g). The mixture was heated at 50° C. for 1 hour, cooled to room temperature, quenched with brine and extracted with ethyl acetate. The organic layer was dried with magnesium sulfate, filtered and concentrated under reduced pressure. The residue was purified by flash column chromatography (silica gel, 25% ethyl acetate:hexanes) to obtain desired product 1.4 g (60%) as colorless oil. MS (DCI/NH3) m/e 265 (M+H)+.

Workup

temperaturecooled to room temperature
customquenched with brine
extractionextracted with ethyl acetate
dry with materialThe organic layer was dried with magnesium sulfate
filtrationfiltered
concentrationconcentrated under reduced pressure
customThe residue was purified by flash column chromatography (silica gel, 25% ethyl acetate:hexanes)

Sources & evidence

ORD record: ord-e24430c2f5b0478ebe16d2baf030804a
Source dataset: uspto-grants-2009_05
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US07528134B2

Reaction notes

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