Highly β-selective mannosylation towards Manβ1-4GlcNAc synthesis : TMSB(C6F5)4 as a lewis acid/cation trap catalyst

Highly β-selective mannosylation of 4,6-O-benzylidene-mannopyrahosyl-N-phenyltrifluoroacetimidate (α/β, 5:95, 93% yield) has been realized by utilizing a dual Lewis acid/cation trap catalyst, TMSB(C 6 F 5 ) 4 . The obtained Manβ1-4GlcNTroc unit can be readily converted to a variety of N-linked oligosaccharides.