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

Temperature

100 °C

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.

1. customDMSO (1.6 mL) was degassed
2. custompurged with nitrogen
3. temperatureAfter cooling
4. additionthe mixture was poured into brine
5. extractionextracted with ethyl acetate
6. dry with materialThe organic layer was dried (MgSO4)
7. filtrationfiltered
8. customThe filtrate was evaporated to dryness
9. customthe residue was purified by chromatography on silica
10. washeluting with a mixture of methanol and DCM with a gradient of 0-15%

ORD record

ord-dc933e5941b0472f9156fe5abfe3a699

Source dataset

uspto-grants-2016_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09440943B2