C. Thom et al., A PRACTICAL SYNTHESIS OF (R)-(-CYCLOHEX-3-ENECARBOXYLIC ACID VIA AN ASYMMETRIC DIELS-ALDER REACTION()), Synthesis, (5), 1993, pp. 475-477
The polymerisation which complicates the ethylaluminum dichloride-cata
lysed asymmetric Diels-Alder reaction between N-propenoylbornane-10,2-
sultam dimethyl-3-thia-4-azatricyclo-[5.2.1.0(1,5)]decane 3,3-dioxide]
and butadiene can be suppressed using galvinoxyl yl-4-oxo-2,5-cyclohe
xadien-1-ylidene)-p-tolyloxyl] leading to a practical and large scale
synthesis of (R)-(+)-cyclohex-3-enecarboxylic acid.