Stereoselective glycosylations using benzoylated glucosyl halides with inexpensive promoters.
Reactions of O-benzoylated glucopyranosyl halide (I, Br), isolated or generated in situ from per-benzoylated glucose (8a) and trimethylsilyl halide, with various alcohols were efficiently promoted by zinc halide (Cl, Br) or N-bromosuccinimide with a catalytic ZnI(2) to give the corresponding 1,2-trans-beta-glucosides in good to high yields. When the anomeric halogenation of 8a was carried out in the presence of reactive alcohols, 1,2-cis-alpha-glucosides were selectively formed.
Murakami
Teiichi
T
Institute for Biological Resources and Functions, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, Japan. t-murakami@aist.go.jp
Sato
Yukari
Y
Shibakami
Motonari
M
D001965:Bromides / Q000737:chemistry; D001974:Bromosuccinimide / Q000737:chemistry; D005960:Glucosides / Q000737:chemistry*; D006031:Glycosylation; D006219:Halogens / Q000737:chemistry*; D007454:Iodides / Q000737:chemistry; D013237:Stereoisomerism; D017967:Zinc Compounds / Q000737:chemistry
D001965:Bromides; D005960:Glucosides; D006219:Halogens; D007454:Iodides; D017967:Zinc Compounds; D001974:Bromosuccinimide; C093802:zinc bromide