Question

3) Amines are often protected with the tert-butyloxycarbonyl (BOC) group. Show the mechanism of formation of the BOC protected amine (a carbamate). Be sure to show all bonds formed/broken and include all intermediates including the appropriate formal charge. Na2CO3 + CO2 + NH NHBOC NaOC(CH3)3 leucine (BOC)20 Do you expect that the carbamate functional group is more or less reactive than an amide towards nucleophilic addition? Briefly explain your reasoning amide carbamate The BOC protecting group can be removed under acidic conditions, such as treatment with trifluoroacid acid (TFA) in dichloromethane. Suggest a mechanism for the reaction below. Note: TFA is a water free acid он NH он CO2 NH3 (TFA)

Answer 1

Bod, o Protection NL N- 一大 6

6 2 02 L

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