Diels-Alder reactions of triazolinedione

Density functional theory has been used to investigate the Diels-Alder reactions of triazolinedione with s-cis- and. y-fran -butadiene. " Combined quantum mechanics-molecular mechanics calculations have been used to investigate the asymmetric Diels-Alder reaction of cyclopentadiene with the complex dienophiles AICI3-methyl acrylate and methoxyaluminium dichloride-acrolein.Equilibrium constants have been determined for the molecular complexes formed from 1-alkyl-1-(2-naphthyl)ethenes and 1-vinylnaphthalene with TCNE in C1(CH2)2C1 at 27.1 °C ... 

The thermal extrusion of sulphur dioxide from sulphones and sulpholene adducts is a well known procedure for producing 1,3- or 1,4-dienes and skipped polyenes. Lithium aluminium hydride has now been shown to effect this extrusion in good yield under mild conditions (refluxing ether)." The technique is similar to, but apparently mechanistically different from, the LiAlH4-promoted retro-Diels-Alder reaction of triazolinedione adducts reported recently by Barton. 

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