[O:1]1[C:5]2([CH2:9][CH:8]=[CH:7][CH2:6]2)[O:4][CH2:3][CH2:2]1.Cl[N:11]([Na])[S:12]([C:15]([CH3:18])([CH3:17])[CH3:16])(=[O:14])=[O:13].[Br-].[Br-].[Br-].C[N+](C)(C)C1C=CC=CC=1.C[N+](C1C=CC=CC=1)(C)C.C[N+](C1C=CC=CC=1)(C)C>C(#N)C>[CH3:16][C:15]([S:12]([N:11]1[CH:8]2[CH:7]1[CH2:6][C:5]1([CH2:9]2)[O:4][CH2:3][CH2:2][O:1]1)(=[O:14])=[O:13])([CH3:18])[CH3:17]To a solution of 1,4-dioxaspiro[4.4]non-7-ene (370 mg, 2.93 mmol) and N-chloro-2-methyl-N-sodiopropane-2-sulfonamide (Intermediate 43; 965 mg, 4.99 mmol) in acetonitrile (16 ml) was added trimethylphenylammonium tribromide (CAS number 4207-56-1; 110 mg, 0.29 mmol) under an atmosphere of nitrogen. The reaction mixture was stirred at room temperature for 2 hours then heated to 40° C. for 18 hours. The reaction mixture was filtered through a plug of silica, washed with diethyl ether and the filtrate concentrated in vacuo. The crude material was purified column chromatography (silica, 0-50% diethyl ether/petroleum) to afford the title compound.
読み込み中…
