Diels–Alder reactions between hexafluoro-2-butyne and bis-furyl dienes: kinetic versus thermodynamic control†
* Corresponding authors
a
Organic Chemistry Department, Faculty of Science, Peoples’ Friendship University of Russia (RUDN University), 6 Miklukho-Maklaya St., Moscow, Russian Federation
E-mail:
fzubkov@sci.pfu.edu.ru
b
V. A. Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 32 Vavilov St., Moscow, Russian Federation
E-mail:
novikovfff@bk.ru
c
National Research Center "Kurchatov Institute", 1 Acad. Kurchatov Sq., Moscow, Russia
E-mail:
yzubav@gmail.com
d
Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, Lisbon 1049-001, Portugal
E-mail:
max@mail.ist.utl.pt
Abstract
The tandem [4+2] cycloaddition between hexafluoro-2-butyne and bis-furyl dienes, like difurfuryl ester, at room temperature leads to the kinetically controlled "pincer"-adducts – annulated 4a,8a-bis(trifluoromethyl)hexahydro-1,4:5,8-diepoxynaphthalenes. On the other hand, if these reactions proceed at 140 °C, only the thermodynamically controlled "domino"-adducts – annulated 2,3-bis(trifluoromethyl)hexahydro-1,4:5,8-diepoxynaphthalenes – are formed. Therefore, a very rare and unexpected example of full kinetic and thermodynamic control in the Diels–Alder reaction is reported in this paper.