Zur Bildung eines Benzo-difurans aus Tetrahydroxy-benzochinon

The reaction of tetrahydroxy-benzoquinone with malononitrile is reinvestigated. Spectroscopic and chemical methods establish the structure of the product formed as 2,6-diamino-4,8-dihydro-4,8-dioxobenzo(1,2-b:4,5-b)difuran (2a). Alkylethers of tetrahydroxy-benzoquinone react with malononitrile to give tetraalkoxytricyanovinyl-phenols (5).

     

Bildung eines hochexplosiven Valenzisomeren des Indens aus Dilithiopentalen und Chlorcarben

Formation of a Highly Explosive Valence Isomer of Indene from Dilithiopentalene and Chlorocarbene The principal product of the reaction of dilithiopentalene ( 3 ) with methyllithium and methylene chloride is shown by difference-FT-NMR, spectroscopy to be tetracyclo[4.3.0.0^3,5.0^4,6]nona-1,7-diene ( 8 ). This laterally bridged benzvalene derivative explodes violently at temperatures as low as ?40° when concentrated. Controlled rearrangement in diluted solution gives indene ( 4 ). The key step in the formation of the tetracyclic C₉H₈-compound 8 is suggested to be an intramolecular 1,4-carbene addition.     

Die Bildung eines Chloroformhydrates

Ohne Zusammenfassung