Tricyclohexylphosphine → 6-Methyl-3'-nitro-4,4'-bipyridin-2-amine

Participants

Reaction Conditions

Reaction Steps

To a solution of 4-chloro-6-methylpyridin-2-amine (1.0 equiv.) in dioxane was added bis(pinacolato)diboron (2.0 equiv.), Pd2(dba)3 (0.05 equiv.), PCy3 (0.075 equiv.), and KOAc (3.0 equiv.). The reaction was heated for 3 hrs at 110° C., then filtered, and concentrated. The crude material was dried under vacuo, then dissolved in DME/2M Na2CO3 (3:1), 4-chloro-3-nitropyridine (2.0 equiv.) was added, followed by Pd(dppf)Cl2-DCM (0.1 equiv.). The mixture was heated to 120° C. for 1 hr, then EtOAc and H2O were added, the organic phase was removed, dried with Na2SO4, and concentrated. Purification via SiO2 column chromatography eluting with EtOAc yielded 6-methyl-3′-nitro-4,4′-bipyridin-2-amine in 35% yield. LCMS (m/z): 231.1 (MH+) LC Rt=1.47 min.

Provenance & Evidence