1,4-Dioxane → [6-[2-[Methyl-[(2-methylpropan-2-yl)oxycarbonyl]amino]propanoylamino]-2-[2-tri(propan-2-yl)silylethynyl]pyridin-3-yl]boronic acid

Participants

Reaction Conditions

Reaction Steps

A mixture of tert-butyl-N-[1-[[5-bromo-6-[2-tri(propan-2-yl)silylethynyl]pyridin-2-yl]-amino]-1-oxopropan-2-yl]-N-methylcarbamate C1a (51 g, 90 mmol), bis(neopentyl glycolato)diboron (40.5 g, 179 mmol), KOAc (26.4 g, 269 mmol), 1,1′-Bis(diphenyl-phosphino)ferrocene]dichloropalladium(II) (3.3 g, 4.5 mmol) and dioxane (400 ml) is stirred under argon atmosphere for 17 h at 50° C. The mixture is diluted with DCM and extracted with a saturated aqueous solution of NaHCO3. The combined organic layers are dried over MgSO4 and concentrated in vacuo. The product is purified by NP chromatography. Yield: 21.9 g (48%). HPLC-MS: M+H=504; tR=2.17 min (*Method—4).

Provenance & Evidence