New Heptafulvene Derivatives

Abstract

whereas the newly discovered disproportionation according to route B can be regarded as a hydrogenation of an azo double bond [4]. The structure (3) can be considered as a transition state, especially since diimide produced from benzenesulfonylhydrazide hydrogenates added tolane stereospecifically to gibe cis-stilbene in at least 95 "/, yield, according to infrared analysis.The consequences of this auto-hydio~eii:rtion ore currently being investigated. Received, February 13th. 1963 [Z 449/279 IE] [ I ] S. Hiinig and H.

Chemistry of malononitrile

“…When an excess of phosphorus pentachloride is used, 208 is formed in 85% yield. An equimolar ratio of reactants at 20-25°g ave a 75-80% yield of 1,1,3,5-tetrachloro-l ,2,6-phosphadiazine (209). The cyclizations probably proceed via Scheme XV.…”

Fulvenes and substituted fulvenes

“…Ethoxytropylium fluoroborate (CCI), formed from tropone and triethyloxonium fluoroborate, reacts with malononitrile in the presence of bases to give the orange , -dicyanoheptafulvene (CC) (156, 297), which, indeed, has the high dipole moment of 7.49 D), indicating a significant contribution of a dipolar structure. Equally, methyltropylium perchlorate (2 moles) and ethyl orthoformate condense in acetic anhydride to the deep blue [3-(cycloheptatrienylidene)allyl]tropylium perchlorate (CCII) (156). An alternative method consists in the dehydrogenation (with bromine, Nbromosuccinimide, or chloranil) of tropylmalononitrile, diethyl tropylmalonate and ethyl tropylcyanoacetate behaving analogously (297, 457).…”