27. Benzcyclooctatetraenes. Part IV. 1 : 2 : 3 : 4 : 5 : 6-Tribenz-Δ^{1 : 3 : 5 : 7}-cyclooctatetraene

Modeling chromium sulfate complexes in relation to chromium tannage in leather technology: a computational study

“…23 Comparison of monodentate with bidentate complexation of acetate and formate ions with the chromium ion shows their preference for being monodentate (Eqns [7]- [10]). 23 Comparison of monodentate with bidentate complexation of acetate and formate ions with the chromium ion shows their preference for being monodentate (Eqns [7]- [10]).…”

“…3 Theis showed that thermal stability is related to swelling of protein at the moment of tannage. It has been shown that carboxyl groups become partly displaced by hydroxyl groups at high pH values, [6][7][8][9] so that the bond between protein and chromium may be broken by raising the pH value too far. 4 Un-ionized acid does not form a stable coordination compound with chromium, so that the pH of tannage will govern the extent of coordination of carboxyl groups.…”

The Synthesis of Substituted Terphenyls

“…A few substituted terphenyls have been obtained by the degradation of higher polyphenyls. For instance, the oxidation of tetraphenylene with chromic oxide affords o-terphenyI-2,2"-dicarboxylic acid (129). Also, 4-nitro-m-terphenyl-5'-carboxylic acid is obtained by similar oxidation of the nitroquaterphenyl (XXIV) (133).…”

The Chemistry of Eight-Membered Carbocycles.

“…It is stable to potassium permanganate in acetone (113) but is oxidized with chromic acid in acetic acid to give a dicarboxylic acid anhydride (VII). While II was found to be aromatic (as it should be since all the double bonds are present in the benzene rings), VIII was found to add bromine and to absorb one molar equivalent of hydrogen readily upon catalytic hydrogenation (141).…”