Tri-tert-butylphosphine tetrafluoroborate → methyl cis-(1aRS,7bSR)-5-[2-((Z)-3-diethylaminoprop-1-enyl)-4-fluorobenzenesulfonylmethyl]-1,1a,2,7b-tetrahydrocyclopropa[c]chromene-4-carboxylate

Participants

Reaction Conditions

Reaction Steps

A mixture of methyl cis-(1aRS,7bSR)-5-(2-bromo-4-fluorobenzenesulfonylmethyl)-1,1a,2,7b-tetrahydrocyclopropa[c]chromene-4-carboxylate (Intermediate 5, 0.66 g), N,N-diethyl-N—((Z)-1-tributylstannanylprop-1-en-3-yl)amine (Intermediate 2, 1.17 g), tri-tert-butylphosphonium tetrafluoroborate (0.145 g), Iris-(dibenzylideneacetone)-dipalladium (0.066 g) in dioxane (16 mL) and DMSO (1.6 mL) was degassed and purged with nitrogen, then heated at 100° C. for 1.5 hours. After cooling, the mixture was poured into brine and extracted with ethyl acetate. The organic layer was dried (MgSO4) and filtered. The filtrate was evaporated to dryness and the residue was purified by chromatography on silica, eluting with a mixture of methanol and DCM with a gradient of 0-15% to give methyl cis-(1aRS,7bSR)-5-[2-((Z)-3-diethylaminoprop-1-enyl)-4-fluorobenzenesulfonylmethyl]-1,1a,2,7b-tetrahydrocyclopropa[c]chromene-4-carboxylate (0.72 g) as a glass.

Provenance & Evidence