Classical Example of Total Kinetic and Thermodynamic Control: The Diels–Alder Reaction between DMAD and Bis-furyl Dienes
KseniyaK. Borisova, Elizaveta A. Kvyatkovskaya, Eugeniya V. Nikitina, Rinat R. Aysin, Roman A. Novikov, Fedor I. Zubkov
Index: 10.1021/acs.joc.8b00336
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Abstract
A rare example of chemospecificity in the tandem Diels–Alder reaction of activated alkynes and bis-dienes has been revealed. The reaction between bis-furyl dienes and DMAD occurs at 25–80 °C and leads to kinetically controlled “pincer” adducts, 4a,8a-disubstituted 1,4:5,8-diepoxynaphthalenes. On the contrary, only thermodynamically controlled “domino” adducts (2,3-disubstituted 1,4:5,8-diepoxynaphthalenes) are formed in the same reaction at 140 °C. The “pincer” adducts can be transformed to the “domino” adducts at heating. The rate constants for reactions of both types were calculated using dynamic 1H NMR spectroscopy.