“…Consequently, chelated intermediates formation appeared far less efficient for iminoesters 1a , 1b than for ketoesters 2a , 2b , 2c . This is in contradiction with previous results described in the literature but nevertheless for less hindered imino and enaminoesters 34, 36. In our case, the stereochemical outcome of the reduction reaction affording the major anti diastereomer 5a , 5b could be explained assuming a predominantly non chelated Felkin Anh model: the presence of both hindered methylbenzyl moiety on the imino group and the quaternary carbon atom in the α‐position prevents the formation of the cyclic chelated intermediate.…”