Potassium Phosphate, Tribasic → 2,3-difluoro-5-(1-methyl-1H-pyrazol-4-yl)pyridine

HRID 40346

Reaction equation

Cl[C:2]1[CH:3]=[C:4]([F:9])[C:5]([F:8])=[N:6][CH:7]=1.[O-]P([O-])([O-])=O.[K+].[K+].[K+].[CH3:18][N:19]1[CH:23]=[C:22](B2OC(C)(C)C(C)(C)O2)[CH:21]=[N:20]1.CC(C1C=C(C(C)C)C(C2C=CC=CC=2P(C2CCCCC2)C2CCCCC2)=C(C(C)C)C=1)C>C([O-])(=O)C.[Pd+2].C([O-])(=O)C.CCOC(C)=O.O.O1CCOCC1>[F:8][C:5]1[C:4]([F:9])=[CH:3][C:2]([C:22]2[CH:21]=[N:20][N:19]([CH3:18])[CH:23]=2)=[CH:7][N:6]=1

Participants

Conditions

Temperature: 100 °C

Procedure

A sealable flask was charged with 5-chloro-2,3-difluoropyridine (1.541 g, 10.3 mmol), palladium(ii) acetate (0.116 g, 0.515 mmol), potassium phosphate tribasic (6.56 g, 30.9 mmol), 1-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole (2.57 g, 12.4 mmol), and X-Phos (0.491 g, 1.03 mmol). The flask was sealed with a septum cap, then dioxane (20 mL) and H2O (2 mL) were added. The resulting mixture was sparged with N2 for 10 min, and then heated at 100° C. for 2 h. The solution was cooled to rt and then concentrated and purified by flash chromatography using eluent 99:1 Hexanes:EtOAc to 60:40 Hexanes:EtOAc gradient to afford 2,3-difluoro-5-(1-methyl-1H-pyrazol-4-yl)pyridine (1.78 g, 88.5% yield) as a colorless film. LRMS (ESI) m/z calcd for C9H7F2N3 (M+H) 197.1. found 197.4.

Workup

customThe flask was sealed with a septum
customcap
customThe resulting mixture was sparged with N2 for 10 min
temperatureThe solution was cooled to rt
concentrationconcentrated
custompurified by flash chromatography

Sources & evidence

ORD record: ord-d9fac620b91544978d069c4c72220021
Source dataset: uspto-grants-2013_09
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08524900B2

Linked notes

Loading…