Potassium Phosphate, Tribasic → HCID 118441544, compound

Temperature

100 °C

Degassed toluene (48 mL) was added to a mixture of C3 (6.01 g, 19.7 mmol), tert-butyl carbamate (3.45 g, 29.4 mmol), and powdered potassium phosphate (12.6 g, 59.4 mmol), and the mixture was degassed with a stream of nitrogen. In a separate vessel, tris(dibenzylideneacetone)dipalladium(0) (97%, 1.86 g, 1.97 mmol) and di-tert-butyl[2′,4′,6′-tri(propan-2-yl)biphenyl-2-yl]phosphane (98%, 428 mg, 0.99 mmol) were combined with degassed toluene (6 mL) and heated at 100° C. for 2 minutes with stirring; the dark purple mixture changed to a dark maroon color during this activation. The Pd-ligand complex was added via syringe into the mixture containing C3, and the vessel was rinsed with degassed toluene (6 mL), which was also was added to the reaction mixture. The reaction mixture was heated at 100° C. for 20 hours, whereupon it was allowed to cool to room temperature and then filtered through diatomaceous earth. The filter pad was washed with ethyl acetate (2×50 mL), and the combined filtrates were concentrated in vacuo. The resulting oil was purified by chromatography on silica gel (Gradient: 5% to 80% ethyl acetate in heptane), affording the product as a fluffy yellow solid. Yield: 5.16 g, 15.1 mmol, 77%. 1H NMR (500 MHz, CDCl3) δ 7.22-7.30 (br s, 1H, assumed; partially obscured by solvent peak), 7.12-7.21 (br s, 1H), 4.3-4.5 (v br s, 1H), 3.93 (AB quartet, downfield doublet is broadened, JAB=12.7 Hz, ΔνAB=27.2 Hz, 2H), 3.73 (br d, half of AB quartet, J=7.4 Hz, 1H), 3.68 (dd, half of ABX pattern, J=7.3, 4.7 Hz, 1H), 3.63-3.7 (m, 1H), 3.24 (ddd, J=11.6, 6.8, 4.9 Hz, 1H), 1.88 (ddd, J=14.2, 6.8, 2.0 Hz, 1H), 1.52 (s, 9H), 1.42 (ddd, J=14.1, 11.7, 11.7 Hz, 1H), 1.27 (d, J=6.1 Hz, 3H).

1. customDegassed toluene (48 mL)
2. customthe mixture was degassed with a stream of nitrogen
3. washthe vessel was rinsed with degassed toluene (6 mL), which
4. additionwas also was added to the reaction mixture
5. temperatureThe reaction mixture was heated at 100° C. for 20 hours, whereupon it
6. temperatureto cool to room temperature
7. filtrationfiltered through diatomaceous earth
8. washThe filter pad was washed with ethyl acetate (2×50 mL)
9. concentrationthe combined filtrates were concentrated in vacuo
10. customThe resulting oil was purified by chromatography on silica gel (Gradient: 5% to 80% ethyl acetate in heptane)

ORD record

ord-c16c872eeb4945958eec92d8635b335d

Source dataset

uspto-grants-2016_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09428523B2