Protective groups benzoate

This ester was designed as a protective group for the 2-position in glycosyl donors. It has the stability of the benzoate during glycosylation, but has the ease of removal of the chloroacetate. It is readily introduced through the acid chloride... 

As an alternative reaction process, nucleophilic substitution reactions of (1,3/2,4,6)-4-bromo-6-(bromomethyl)-l, 2,3-cyclohexanetriol triacetate (51) with benzoate ions furnished 49 in poor yield after exchange of the protective groups. ... 

These photoinduced reactions proceed in fair to good yields (50-80%) and tolerate a variety of protecting groups at C-6, e.g., acetate, benzoate, methyl, and benzyl. 

The solid-phase synthesis of oligosaccharides is usually performed using acid-resistant linkers and protective groups, because of the slightly acidic reaction conditions required for glycosylations (Section 16.3). Hydroxyl group protection is conveniently achieved by conversion into carboxylic esters, such as acetates, benzoates, or nitro-benzoates. Support-bound esters of primary or secondary aliphatic alcohols can be cleaved by treatment with alcoholates [97-99] (Table 7.8), with DBU in methanol, with hydrazine in DMF [100] or dioxane [101], or with ethylenediamine [102], provided that a linker resistant towards nucleophiles has been chosen. 

The anomeric bromination can result from photosubstitution of other positions in the ring moiety. Very recenly, bromination of fully protected I-2-O-benzylidenated pyranoses with bromotrichloromethane and U.V. light or NBS yields 2-O-benzoyl glycosylbromides which may be converted in situ to glycosides and disaccharides in good yields (Scheme 2). These reaction conditions are compatible with protective groups like esters (acetates, benzoates, tosylates) and silyl ethers. 

Corey lactone where (P) is a protecting group such as acetate, benzoate, or tetrahydropyranyl... 

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