Dichloromethane → Ethyl 5-(4,4-dimethylcyclopent-1-en-1-yl)-4-methylisoxazole-3-carboxylate

Temperatur

90 °C

To a 2-5 mL microwave vial containing a solution of 2-(4,4-dimethylcyclopent-1-en-1-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (214 mg, 0.966 mmol) in acetonitrile (2 mL), ethyl 5-bromo-4-methylisoxazole-3-carboxylate (Intermediate A) (226 mg, 0.966 mmol) was added followed by K2CO3 (400 mg, 2.90 mmol), PdCl2(dppf).CH2Cl2 adduct (Alfa Aesar) (79 mg, 0.097 mmol) and water (1 mL). The vial was flushed with nitrogen, sealed and heated in the microwave (Biotage Smith Initiator) at 90° C. for 1 hour. The resulting mixture was filtered through Celite®, washing with EtOAc (50 mL). The filtrate was washed with water (50 mL), brine (50 mL), dried over MgSO4, filtered and concentrated under reduced pressure to give a brown oil. The crude material was adsorbed onto silica and purification by chromatography eluting with 100% iso-hexane afforded the title compound;

1. additionwas added
2. customThe vial was flushed with nitrogen
3. customsealed
4. filtrationThe resulting mixture was filtered through Celite®
5. washwashing with EtOAc (50 mL)
6. washThe filtrate was washed with water (50 mL), brine (50 mL)
7. dry with materialdried over MgSO4
8. filtrationfiltered
9. concentrationconcentrated under reduced pressure
10. customto give a brown oil
11. customThe crude material was adsorbed onto silica and purification by chromatography
12. washeluting with 100% iso-hexane

ORD-Eintrag

ord-44277bd31212449f94561d2d1d463e31

Quelldatensatz

uspto-grants-2016_08

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US09403810B2