10.1021/jo062630a.s001
Alejandro F. Barrero
Alejandro F.
Barrero
M. Mar Herrador
M. Mar
Herrador
José F. Quílez del Moral
José
F. Quílez del Moral
Pilar Arteaga
Pilar
Arteaga
Jesús F. Arteaga
Jesús F.
Arteaga
Horacio R. Diéguez
Horacio R.
Diéguez
Elena M. Sánchez
Elena M.
Sánchez
Mild Ti<sup>III</sup>- and Mn/Zr<sup>IV</sup>-Catalytic Reductive Coupling of Allylic
Halides: Efficient Synthesis of Symmetric Terpenes<sup>†</sup>
American Chemical Society
2007
allylic halides
Mn
TiIII
catalyst
2007-04-13 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Mild_Ti_sup_III_sup_and_Mn_Zr_sup_IV_sup_Catalytic_Reductive_Coupling_of_Allylic_Halides_Efficient_Synthesis_of_Symmetric_Terpenes_sup_sup_/3013114
Two new efficient methods for the regioselective homocoupling of allylic halides using either catalytic
Ti<sup>III</sup> or the combination Mn/Zr<sup>IV</sup> catalyst have been developed. The regio- and stereoselectivity of the
process proved to increase significantly when the Mn/Zr<sup>IV</sup> catalyst is used as the coupling reagent and
when cyclic substituted allylic halides are used as substrates. The use of Lewis acids such as collidine
hydrochloride allowed the quantity of catalyst to be lowered up to 0.05 equiv. We have proved the
utility of these protocols with the synthesis of different terpenoids such as (+)-β-onoceradiene (<b>1</b>), (+)-β-onocerine (<b>2</b>), squalene (<b>5</b>), and advanced key-intermediates in the syntheses of (+)-cymbodiacetal (<b>3</b>)
and dimeric <i>ent</i>-kauranoids as xindongnin M (<b>4a</b>).