반응 #80549

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(R)-3-(N,N-Dicyclobutylamino)-8-fluoro-5-trifluoromethylsulfonyloxy-3,4-dihydro-2H-1-benzopyran

DMF methanol

carbonmonoxide

triethylamine

→

title compound

수율 78.0%

Methyl (R)-3-(N,N-Dicyclobutylamino)-8-fluoro-3,4-dihydro-2H-1-benzopyran-5-carboxylate

수율 78.0%

반응 조건

후처리

1. 1
   기타degassed
2. 2
   기타the reaction mixture was degassed
3. 3
   온도to cool
4. 4
   기타the solvent was removed in vacuo
5. 5
   추출extracted
6. 6
   건조The combined ether portions were dried (MgSO4)
7. 7
   여과filtered
8. 8
   기타the solvent removed in vacuo
9. 9
   기타to give the crude residue

실험 절차

(R)-3-(N,N-Dicyclobutylamino)-8-fluoro-5-trifluoromethylsulfonyloxy-3,4-dihydro-2H-1-benzopyran (0.82 g, 1.94 mmol) was dissolved in a solution of DMF/methanol (6:2, 15 mL) and then degassed followed by the inlet of carbonmonoxide (×3). With a slight positive pressure of carbonmonoxide, palladium(II)-acetate (14 mg), 1,3-bis(diphenylphosphino)propane (25 mg) and triethylamine (0.60 mL, 4.3 mmol) were added and the reaction mixture was degassed and subjected to carbonmonoxide once again. The reaction was heated to 70° C. under carbornmonoxide atmosphere with vigorous stirring for 5.5 h. The reaction was allowed to cool and the solvent was removed in vacuo. The remains were taken into a 2M solution of NH3 and then extracted, twice, with diethyl ether. The combined ether portions were dried (MgSO4), filtered, and the solvent removed in vacuo to give the crude residue. Chromatography on silica (eluent: 12.5% ethyl acetate/hexane) gave 501 mg (78% yield) of the title compound as a clear oil. [α]21D =-138.2° (C=0.1; CHCl3) GC-MS (70 eV) M=333 (4%).

출처