Polyhalogenated heterocyclic compounds .41. Cycloaddition reactions involving hexafluorobut-2-yne and 1,1,1,2,4,4,4-heptafluorobut-2-ene

Cycloadducts, formed by addition of hexafluorobut-2-yne, may be transformed into bis(trifluoromethyl)-benzene, -phenol and -furan derivatives, Tetrakis(trifluoromethyl)benzene may also be produced. Heptafluorobut-2-ene 2 is also a very efficient dienophile for reactions with cyclopentadiene and furan, Reaction of 2 with furan derivatives at elevated temperatures gives a very effective 'one pot' synthesis of 3,4-bis(trifluoromethyl)furan derivatives.