Hydrocarbons dianions

The major oxidation product isolated was anthracene, perhaps formed in part from the hydroperoxide (I). However, significant amounts of potassium superoxide accompanied the anthracene. This result suggests that the major source of anthracene involved the oxidation of the dianion. In pure DMSO in the presence of excess potassium tert-butoxide, a trace of oxygen converts 9,10-dihydroanthracene, 9,10-dihy-drophenanthrene, or acenaphthene to the hydrocarbon radical anions. These products are apparently formed in the oxidation of the hydrocarbon dianions. 

VI. Heterocyclic Betaines Isoelectronic with Even Alternant Hydrocarbon Dianions... 

Randic, M. (1989). Aromaticity in Polycyclic Conjugated Hydrocarbons Dianions. J.Mol.Struct (Theochem), 185, 249-274. 

A comprehensive review on lanthanocene catalysts in selective organic synthesis has been published by Molander and Romero.37 Petrov et al,39 have reviewed the synthesis, structure, and reactivity organolanthanides RLnX (R = alkyl, aryl X = halogen) and lanthanide compounds with aromatic hydrocarbon dianions. 

Dianions derived from sulfur and oxygen containing polycyclic systems have not been reported until very recently. The weak carbon-sulfur bond could discourage attempts to prepare such dianions. Sulfur removal studies by alkali metals were successful due to the properties of the carbon-sulfur bond 182,183). Reductive alkylation studies on model compounds which are relevant to sulfur containing systems demonstrated the stability of hydrocarbon dianions 182). A spectroscopic study performed under mild conditions afforded the characterization of sulfur and oxygen containing dianions 184 186). Benzo[b]thiophene, (73), 1,3-diphenylbenzo[c]thiophene (74) and l,3-diphenylbenzo[c]furan (75) form the respective dianions at low temperature. 

The structural chemistry of solvated alkali metal derivatives of planar polycyclic hydrocarbon dianions has been well investigated. Monomeric complexes have been isolated with hydrocarbons such as naphthalene, anthracene, perylene, pentalene,... 

M. Randic, D. Plavsic, and N. Trinajstic, Aromaticity in polycyclic conjugated hydrocarbon dianions, THEOCHEM.—J. Mol. Struct. 54 (1989) 249-274. 

Hydrocarbon dianion compounds. Enthalpies of formation of ArH ",2Na (ArH= Naph, Anth, tetracene, pentacene, pyrene, perylene, etc.) from ArH and Na were calculated to be similar (. 40 k cal mol"b- This suggests that entropy effects rather than electron affinities account for the difficulty in forming dianions of the smaller hydrocarbons. N.m.r. spectra have been obtained in THF for K2 acepentalenide (from the hydrocarbon and BuLi,Pe 0K), Na2 bifluoran-... 

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