Nucleophilic Cleavage of Amides and Carbamates

Amides are generally very resistant towards nucleophilic cleavage. Safety-catch linkers, such as those described in Section 3.1.2.3, can, however, be cleaved by amines to yield amides (Entries 1 and 2, Table 3.15). Entry 4 in Table 3.15 is an example of a 

Entry Loaded resin Cleavage conditions Product, yield (purity) Ref. 

Support-bound /V-sulfonyl carbamates, which can be prepared by N-sulfonylation of resin-bound carbamates, are susceptible to nucleophilic cleavage. These intermediates enable the solid-phase preparation of A-ary I- or /V-alkylsulfonamides using inexpensive hydroxymethyl polystyrene (Entries 8 and 9, Table 3.15). Polystyrene-bound carbamates can also be cleaved by treatment with acyl halides in the presence of Lewis acids (Entry 4, Table 3.16). 

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