Pyridine N-Oxide → Benzopyran
반응식
[N+]1([O-])[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.I([C:10]1C=C[CH:13]=[CH:12][CH:11]=1)=O.CCCCCC.C([OH:25])(C)C>C(#N)C>[O:25]1[C:13]2[CH:12]=[CH:11][CH:10]=[CH:6][C:5]=2[CH:4]=[CH:3][CH2:2]1참가 물질
5
반응 조건
- 온도
- 0 °C
실험 절차
26.2 mg of compound [IV-1] (0.10 mmol) and 2.6 mg of the compound [I-1] (2.5 μmol) were dissolved in 1.25 mL of an acetonitrile solution of pyridine-N-oxide (0.02M, 0,025 mmol), followed by cooling to 0° C. To the resulting solution was added 44.0 mg of iodosylbenzene (0.20 mmol) all at once under a nitrogen atmosphere, followed by stirring at 0° C. for twenty four hours. Insoluble matters were filtered out through Celite, the filtrate was concentrated, and the residues were purified by silica gel column chromatography (eluent: hexane-ethyl acetate=8:2-4:6) to obtain the intended compound. (epoxide yield: 20. 1 mg (72%)) (asymmetric yield: 98% e.e.) (Daicel Chiralcel OJ, hexane-isopropanol=1:1, flow rate: 0.5 mL/min.)