Ethynylcyclobutane → HCID 57908178, compound

Temperature

25 °C

To the solution of tert-butyl 6-chloro-4-iodopyridin-3-ylcarbamate (7.0 g, 19.8 mmol) in Et3N (100 mL) was added the solution of ethynylcyclobutane in THF (prepared in step a), Pd(PPh3)2Cl2 (1.8 g, 2.1 mmol) and CuI (400 mg, 2.1 mmol). The reaction mixture was stirred at 25° C. for 16 h. The mixture was diluted with water and extracted with dichloromethane (3×100 mL). The extract was washed with brine, dried, concentrated in vacuo and purified by chromatography on silica gel (5-10% ethyl acetate in petroleum ether as eluant) to afford tert-butyl 6-chloro-4-(cyclobutylethynyl)pyridin-3-ylcarbamate (3.6 g, 60% yield). 1H NMR (300 MHz, CDCl3) δ: 9.11 (br, s, 1H), 7.22 (s 1H), 6.97 (s, 1H), 3.39-3.25 (m, 1H), 2.48-1.98 (m, 6H), 1.52 (s, 9H).

1. extractionextracted with dichloromethane (3×100 mL)
2. washThe extract was washed with brine
3. customdried
4. concentrationconcentrated in vacuo
5. custompurified by chromatography on silica gel (5-10% ethyl acetate in petroleum ether as eluant)

ORD record

ord-a23c33ff524b4689a4c4dc0b9307cf22

Source dataset

uspto-grants-2015_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09102672B2