Theoretical studies and rational design of organoborane reactions

PISANO, P.L.; GRIMBLAT, N.N.; SAROTTI, A.M.; PELLEGRINET, S.C.

Columbus, Ohio, EEUU

Congreso; Gaussian Workshop Introduction to Gaussian: Theory and Practice; 2010

The Diels-Alder reaction of boron-activated dienophiles is a very useful chemical transformation.1 For example, dihalovinylboranes and dialkylvinylboranes are Diels-Alder dienophiles of exceptional reactivity, regioselectivity and endo-estereoselectivity. This peculiar reactivity arises from the valence of the boron atom of the vinylborane which can generate important secondary orbital interactions with the carbon atoms of the diene during the course of the reaction. In addition, vinylboranes constitute synthetic equivalents of diverse organic compounds such as enols, ketenes, enamines and alkenes. On the other hand, vinylborononates exhibit low reactivity in Diels-Alder reactions. However, in contrast to dialkylboranes, boronates are stable to air and moisture and can be purified by chromatography or destilation. Therefore, the properties of boron-activated dienophiles can be modulated by the rational design of the ligands attached to the boron atom.