Benzaldehyde, 4-hydroxy-3-iodo-5-methoxy- → rac-3-[(3,4-Dihydro-6-hydroxy-2,5,7,8-tetramethyl-2H-1-benzopyran-2-yl)ethynyl]-4-hydroxy-5-methoxybenzaldehyde
反応式
[C:1]([C:3]1([CH3:17])[CH2:8][CH2:7][C:6]2[C:9]([CH3:16])=[C:10]([OH:15])[C:11]([CH3:14])=[C:12]([CH3:13])[C:5]=2[O:4]1)#[CH:2].I[C:19]1[C:20]([OH:29])=[C:21]([O:27][CH3:28])[CH:22]=[C:23]([CH:26]=1)[CH:24]=[O:25]>>[OH:15][C:10]1[C:11]([CH3:14])=[C:12]([CH3:13])[C:5]2[O:4][C:3]([C:1]#[C:2][C:19]3[CH:26]=[C:23]([CH:22]=[C:21]([O:27][CH3:28])[C:20]=3[OH:29])[CH:24]=[O:25])([CH3:17])[CH2:8][CH2:7][C:6]=2[C:9]=1[CH3:16]参加物
3
実験手順
Rac-3,4-dihydro-2-ethynyl-2,5,7,8-tetramethyl-2H-1-benzopyran-6-ol, 2.3 g, was reacted with 4.17 g (15 mmol) of 5-iodovanilline as described in example 1, but extending the reaction time to 4.5 hours. After the usual workup, the residue was chromatographed over 150 g of silica gel using 10% (V/V) of ethyl acetate in methylene chloride. Crystallization from ether/hexane and recrystallization from ethyl acetate/hexane yielded colorless crystals with m.p. 158°-160°.