Methyl chloroformate → methyl (1aRS,7bSR)-5-[N-(2-bromo-4-fluorobenzenesulfonyl)-N-(methoxycarbonyl)amino]-1,1a,2,7b-tetrahydrocyclopropa-[c]chromene-4-carboxylate

HRID 927952Notes

Reaction equation

HRID 927952 reaction equation
[Br:1][C:2]1[CH:7]=[C:6]([F:8])[CH:5]=[CH:4][C:3]=1[S:9]([NH:12][C:13]1[C:22]([C:23]([O:25][CH3:26])=[O:24])=[C:21]2[C:16]([CH:17]3[CH2:27][CH:18]3[CH2:19][O:20]2)=[CH:15][CH:14]=1)(=[O:11])=[O:10].[H-].[Na+].Cl[C:31]([O:33][CH3:34])=[O:32].C(=O)(O)[O-].[Na+]>C1COCC1>[Br:1][C:2]1[CH:7]=[C:6]([F:8])[CH:5]=[CH:4][C:3]=1[S:9]([N:12]([C:13]1[C:22]([C:23]([O:25][CH3:26])=[O:24])=[C:21]2[C:16]([CH:17]3[CH2:27][CH:18]3[CH2:19][O:20]2)=[CH:15][CH:14]=1)[C:31]([O:33][CH3:34])=[O:32])(=[O:10])=[O:11]

Participants

6

Reactant 4

HCID 6586Methyl chloroformateHCID 24758Sodium hydrideHCID 516892Sodium BicarbonateHCID 86713292methyl (1aRS,7bSR)-5-(2-bromo-4-fluorobenzenesulfonylamino)-1,1a,2,7b-tetrahydrocyclopropa[c]chromene-4-carboxylate2×

Product 1

HCID 77979724methyl (1aRS,7bSR)-5-[N-(2-bromo-4-fluorobenzenesulfonyl)-N-(methoxycarbonyl)amino]-1,1a,2,7b-tetrahydrocyclopropa-[c]chromene-4-carboxylateYield 83.5%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Procedure

A solution of methyl (1aRS,7bSR)-5-(2-bromo-4-fluorobenzenesulfonylamino)-1,1a,2,7b-tetrahydrocyclopropa[c]chromene-4-carboxylate (Intermediate 41, 1.7 g) in THF (20 mL) was added to a suspension of sodium hydride (70% oil dispersion, 0.2 g) in THF (10 mL). The resultant solution was stirred for 30 minutes then methyl chloroformate (0.53 g) was added. The resultant mixture was stirred at room temperature overnight. Saturated aqueous sodium bicarbonate was added and the mixture was extracted with ethyl acetate, dried (Na2SO4) and filtered. The filtrate was evaporated to dryness and the residue was purified by chromatography on silica, eluting with a mixture of ethyl acetate and petroleum ether (30%) to give methyl (1aRS,7bSR)-5-[N-(2-bromo-4-fluorobenzenesulfonyl)-N-(methoxycarbonyl)amino]-1,1a,2,7b-tetrahydrocyclopropa-[c]chromene-4-carboxylate (1.6 g) as a white solid.

Workup

  1. extractionthe mixture was extracted with ethyl acetate
  2. dry with materialdried (Na2SO4)
  3. filtrationfiltered
  4. customThe filtrate was evaporated to dryness
  5. customthe residue was purified by chromatography on silica
  6. washeluting with a mixture of ethyl acetate and petroleum ether (30%)

Sources & evidence

ORD record
ord-5287a4c919474c6cac8d2b2f867752d4
Source dataset
uspto-grants-2016_03
Patent number
US09290472B2

Reaction notes

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