Tetrahedron p. 10471 - 10478 (1997)
Update date:2022-08-04
Topics:
Chiappe, Cinzia
Lo Moro, Giacomo
Munforte, Paola
The glycosidation of para substitued phenols with 1,2-anhydro-3,4,6-tri-O-methyl-α-D-glucopyranose. ZnCl2 catalyzed, gives predominatly the corresponding α-anomers. In the presence of an amino base, 1,1,3,3-tetramethylguanidine, however, enhances the β-selectivity, which becomes practically complete when tile reaction is carried out under basic conditions, by addition of K2CO3 and 18-crown-6. A rationaliation based on the lifetime of the oxocarbenium ion intermediate and on the nucleophilicity of the phenols is proposed.
View MoreHebei Tianxiang Biological & Pharmaceutical Co., Ltd
Contact:86-0312-6615158
Address:No 42 fazhan street qingyuan county
Engineering Research Center of Pesticide, Heilongjiang Province
Contact:+86-451-86609001
Address:No.74 of Xuefu Road, Nangang District,
Taizhou Shengxing Chempharm Co.,Ltd
Contact:+86-576-88516600
Address:Yantou Chemical Zone Jiaojiang Taizhou Zhejiang China
Shanghai Hongbang Medical Technology CO.,. Ltd
Contact:13671516988 /18917636693
Address:Room1, No67 Building, Yongde Road369, Wujing Town, Minhang Districy, Shanghai CIty, China.
Tianjin Bright Future Technology Co., Ltd
Contact:0086-22-58016666
Address:NO.136 DongTeng Lake Street Tianjin Economic and Technology Development Area,Tainjin,China
Doi:10.1139/v62-019
(1962)Doi:10.1016/j.mcat.2020.111120
(2020)Doi:10.1055/s-1985-31114
(1985)Doi:10.1021/ja01872a039
(1939)Doi:10.1016/j.poly.2013.01.045
(2013)Doi:10.1016/0022-328X(86)80477-6
(1986)