Protection of Amino Groups Acylation and Dimer Formation

14 PROTECTION OF AMINO GROUPS ACYLATION AND DIMER FORMATION 

H NCHCOf + NaOH amino acid RiOC-HNCHCOjH 

FIGURE 3.14 Protection of amino groups as urethanes by reaction with chloroformates (path 

A side reaction often occurs. Reaction of the anionic product with the chloroformate (path 

B) generates a mixed anhydride that undergoes aminolysis, yielding protected dimer. (Curtius, 1881). 

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