Some reactions of biphenyl-2,2′-dialdehyde

Abstract

The reactions of biphenyI-Z,2'-dialdehyde with zinc and ethyl bromoacetate, with malonic acid and with the phosphorane derived from 2-bromomethylnaphthalene, are described.

Uranium Chemistry in liquid Ammonia: Compounds obtained by adventitious Presence of Moisture or Air

“…[46,47] These findings shall serve as an argument for the proposed intermediates appearing in NH 3 solution, as liquid aNH 3 can be seen as a solvent with similar properties compared to H 2 O. [5][6][7][8]48,49] The exchange of an NH S19.…”

“…However, crystal-lization of U compounds from aqueous solutions is often difficult when no auxiliary organic ligands are present as illdefined, amorphous precipitates are frequently obtained. Liquid anhydrous ammonia, aNH 3 , a water-like solvent, [5][6][7][8] proved to be valuable for U speciation studies as crystallization in the ammonia system seems to be favored. [9,10] The results for the ammonia system can be transferred to the aqueous system within certain limits, and vice versa.…”

Cyclization reactions of 2,2'-disubstituted biphenyls

“…The reaction product of 2,2 '-diformylbiphenyl with ethyl bromoacetate and zinc does not give the expected doubly unsaturated Reformatzky product, but rather a compound which contained one molecule of water more, which showed (uv) only biphenyl absorption and which was saturated toward hydrogen. Structure CXLI has been suggested for this abnormal Reformatzky product (29).…”

A Dinuclear Uranium Complex [{UO2F2(NH3)}2(μ‐F)2]2− from Reaction of TlF and UO2F2 in Liquid Anhydrous Ammonia and Fluoride Ion Affinities for Some Uranyl(VI) Species [UO2Fx]2−x and [UO2Fx(NH3)5−x]2−x

“…[13,14] In general, ionic fluorides are only little soluble or even insoluble in aNH 3 as the lattice energies of fluorides are very high in general and the quite temperaturedependent dielectricity constant of NH 3 is much smaller than the one of water. [3,[15][16][17][18] To increase the solubility of fluorides in liquid NH 3 , it is necessary to add promoters which accept F À ions. First attempts were successful using TiCl 3 or [SiF 4 (NH 3 ) 2 ].…”

“…It was mentioned that the UO 2 2+ cation is a strong F − acceptor, able to abstract a F − anion from the [BF 4 ] − anion, [12] but as of today, no quantitative values for its fluoride ion affinity (FIA) have been published [13,14] . In general, ionic fluorides are only little soluble or even insoluble in aNH 3 as the lattice energies of fluorides are very high in general and the quite temperature‐dependent dielectricity constant of NH 3 is much smaller than the one of water [3,15–18] . To increase the solubility of fluorides in liquid NH 3 , it is necessary to add promoters which accept F − ions.…”