Moreover, the basicity of the support may favor the aldol condensation to diacetone alcohol, with subsequent dehydration to mesityl oxide (even in the absence of acid), whose selectivities are not reported in Table 3.
The third example is to demonstrate that this catalyst is not useful in reductive amination of acetone. Moreover, the absence of DIPA is not due to the exhausted NH3, but to the low amount of isopropylamine formed. DIPA is obtained in a subsequent reaction of imine formation (acetone + isopropylamine) and hydrogenation.
In my opinion, the results described in this manuscript are not so relevant to require an account.