L1: Compare the inversion barrier for ammonia to the inversion barrier of aniline (i.e., the difference between the pyramidal minimum of RNH₂ and the planar TS). Rationalize the difference in chemical terms. What computational evidence supports your rationale?

L2: Based on your results for nitrogenous bases, predict whether methoxide (CH₃O^-) would be a stronger or weaker base than hydroxide (OH^-). Suggest an isodesmic reaction to measure the relative basicities and use Gaussian to test your prediction.

L3: Based on your explanation for the differing C-N rotation barriers for acetamide and the enolate of acetamide, predict whether protonation of the the carbonyl oxygen will increase or lower the C-N rotation barrier for acetamide. Test your prediction by computing barrier for C-N rotation in CH3C(OH)NH2+ at the HF/6-31+G(d) level of theory. Hint: The proper TS conformation is shown at the right and the minimum is the same except for rotation about the C-N bond.