1-Iodonaphthalene → rac-3,4-dihydro-2,5,7,8-tetramethyl-2-[(1-naphthyl)ethynyl]-2H-1-benzopyran-6-ol
Reaktionsgleichung
[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:28]2[C:23](=[CH:24][CH:25]=[CH:26][CH:27]=2)[CH:22]=[CH:21][CH:20]=1>C(Cl)Cl>[CH3:17][C:3]1([C:1]#[C:2][C:27]2[C:28]3[C:23](=[CH:22][CH:21]=[CH:20][CH:19]=3)[CH:24]=[CH:25][CH:26]=2)[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]1Komponenten
4
Versuchsvorschrift
rac-3,4-dihydro-2,5,7,8-tetramethyl-2-[(1-naphthyl)ethynyl]-2H-1-benzopyran-6-ol was prepared by coupling rac-3,4-dihydro-2-ethynyl-2,5,7,8-tetramethyl-2H-1-benzopyran-6-ol with 1-iodonaphthalene under the conditions described in Example 1. It was isolated by chromatography over 40 fold amount of silica gel using methylene chloride. The combined clean fractions were crystallized from hexane and recrystallized from petroleum ether to give colorless crystals with m.p. 127°-128°.