Dimethylacetamide → tert-Butyl 5-(tert-butyldiphenylsilanyloxy)-3-{4-cyclopropyl-5-[3-(2-ethylbutyl)cyclobutyl]isoxazol-3-yl}valerate

Participants

Reaction Conditions

Reaction Steps

tert-Butyl 5-(tert-butyldiphenylsilanyloxy)-3-{5-[3-(2-ethylbutyl)cyclobutyl]-4-iodoisoxazol-3-yl}valerate (4.96 g), 2-cyclopropyl-4,4,5,5-tetramethyl-[1,3,2]dioxaborolane (1.68 g), tripotassium phosphate (5.66 g), PdCl2(PPh3)2 (468 mg) and N,N-dimethylacetamide (50 mL) were mixed. The mixture was stirred at 80° C. for 5 hr. To the reaction mixture were added ethyl acetate (50 mL) and Celite at RT, and the mixture was filtered. The collected solid was washed with ethyl acetate (50 mL×2). The filtrate was washed with water/brine=1/1 (100 mL×2) and brine (50 mL), then dried over sodium sulfate. The sodium sulfate was filtered off and the filtrate was concentrated in vacuo. The resultant residue was purified by silica gel column chromatography (Eluent: ethyl acetate/hexane=1/50→1/40→1/30→1/20) to give the title compound (2.86 g).

Provenance & Evidence