Theoretical exploration of a diene-transmissive hetero-Diels–Alder strategy to synthesize boron-functionalized octahydroquinolines

Abstract

A diene-transmissive hetero-Diels–Alder strategy, grounded in previous experimental works and employing boronated dienophiles, is proposed for the synthesis of boron-bearing octahydroquinolines. To assess its feasibility, three representative reactions were investigated, and their thermodynamics were evaluated in toluene and acetonitrile at various temperatures using the ωB97X-D level of theory. The peri-, regio-, stereo-, and π-facial selectivities were predicted. The reaction mechanisms were elucidated through exploration of the reaction pathways and topological studies using the Electron Localization Function and Independent Gradient Model. The predictions are consistent with available experimental work and show that the reactions are feasible with low to moderate polarity. The results also demonstrate that the selectivity of the reactions can in some cases be tuned by judicious choice of reaction conditions to deliver specific products with high selectivity.