The use of insoluble promoters

Other first generation insoluble promoters that include silver tosylate [26], silver salicylate [27], silver imidazolate [28] and silver carbonate [29] have proved 

This methodology was further enhanced by the realisation that an acyl protecting group at the C-2 position effectively hinders the formation of a carbonium ion intermediate [31]. This phenomenon was exploited by Paulsen and co-workers in the coupling of mannoside donor 11 with the GlcNAc precursor acceptor 12 by activation with silver silicate, to afford the 3-disaccharide 13 in a 65% yield (Method 1) [32]. 

Silver silicate promoted (3-mannosylation of bromo mannopyranosyl donors [32]. 

Notes and discussion. This method allows efficient entry to 4-(9-(4-(9-acetyl-3,6-di-(9-allyl-2-(9-benzyl- 3-D-mannopyranosyl)-l,6-anhydro-2-azido-3-0-benzyl-2-deoxy-(3-D-glucopranose by use of the silver silicate catalyst procedure. The target is of use for entry to a branched (3-mannose containing pentasaccharide, present within A -glycoproteins. 

Round bottomed flasks (1 X 100 ml, 1 X 50 ml) with rubber septa and magnetic stirrer bars Magnetic stirrer 

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