Trimethyl borate → [4-(Tert-butoxycarbonyl)-2,6-diethoxyphenyl]boronic acid

反応式

Br[C:2]1[C:14]([O:15][CH2:16][CH3:17])=[CH:13][C:5]([C:6]([O:8][C:9]([CH3:12])([CH3:11])[CH3:10])=[O:7])=[CH:4][C:3]=1[O:18][CH2:19][CH3:20].[Li]CCCC.[B:26](OC)([O:29]C)[O:27]C>C1COCC1>[C:9]([O:8][C:6]([C:5]1[CH:13]=[C:14]([O:15][CH2:16][CH3:17])[C:2]([B:26]([OH:29])[OH:27])=[C:3]([O:18][CH2:19][CH3:20])[CH:4]=1)=[O:7])([CH3:12])([CH3:11])[CH3:10]

参加物

実験手順

To a stirred solution of tert-butyl 4-bromo-3,5-diethoxybenzoate (1 g) in THF (20 ml) was added n-BuLi (1.6M in hexane, 3.6 ml) at −78° C. under argon atmosphere and stirred at the same temperature for 1 h. To the mixture was added B(OMe)3 (777 ul) at −78° C. and the mixture was allowed to warm up to at room temperature. After stirring for further 1 h, the mixture was poured into ice-HCl aq., extracted with EtOAc, washed with brine and dried over sodium sulphate. After filtration and concentration, the residue was purified by silicagel column chromatography (hexane/EtOAc) to give the title product as a colorless solid.