Multicomponent reactions [1] that generate complex, functionalized structures from simple substrates are very attractive step-economical strategies in target-oriented synthesis.[2] We have recently reported on the three-component hetero [4+2] cycloaddition/allylboration reaction [3] for the preparation of a-hydroxyalkylated piperidines [4] and furans [5a] (Scheme 1). In the case of piperidines, this one-pot process is initiated by a hetero-Diels-Alder reaction between boronate-substituted hydrozonobutadienes (1) and electron-poor dienophiles. The formation of the resulting cycloadduct unmasks an allylboronate that adds in situ onto aldehydes to provide polysubstituted piperidine products in a highly stereoselective fashion.We were interested in the challenge of adapting this process to access 2,6-disubstituted piperidine units [6] such as those featured in the palustrine class of alkaloids exemplified