Theoretical exploration of 2,2'-bipyridines as electro-active compounds in flow batteries.

Compounds from the 2,2'-bipyridine molecular family were investigated for use as redox-active materials in organic flow batteries. For 156 2,2'-bipyridine derivatives reported in the academic literature, we calculated the redox potential, the pKa for the second deprotonation reaction, and the solubility in aqueous solutions. Using experimental data on a small subset of derivatives, we were able to calibrate our calculations.

Reversible sigma C-C bond formation between phenanthroline ligands activated by (C5Me5)2Yb.

The electronic structure and associated magnetic properties of the 1,10-phenanthroline adducts of Cp*2Yb are dramatically different from those of the 2,2'-bipyridine adducts. The monomeric phenanthroline adducts are ground state triplets that are based upon trivalent Yb(III), f(13), and (phen(•-) ) that are only weakly exchange coupled, which is in contrast to the bipyridine adducts whose ground states are multiconfigurational, open-shell singlets in which ytterbium is intermediate valent ( J. Am.

Unusual activation of H2 by reduced cobalt complexes supported by a PNP pincer ligand.

The reactivity of cobalt complexes supported by a PNP pincer ligand towards H2 varies depending on whether the N-donor atom is protonated; the synthesis of [(HPNP)CoCl(H)2] (2), [(PNP)CoH]2 (4), and the trihydride species [(HPNP)CoH3] (7) (HPNP = HN(CH2CH2P(i)Pr2)2) are described.

(2,2'-Bipyrid-yl-κ(2) N,N')bis-(η(5)-penta-methyl-cyclo-penta-dien-yl)barium.

In the title compound, [Ba(C10H15)2(C10H8N2)], the Ba-N distances are 2.798 (3) and 2.886 (3) Å, and the Cp ring centroid distances to Ba(2+) are 2.

5,6-Dimeth-yl-1,10-phenanthroline.

In the title compound, C14H12N2, the N⋯N distance is 2.719 (1) Å. The N-C-C-N torsion angle [0.

Chemistry of reduced monomeric and dimeric cobalt complexes supported by a PNP pincer ligand.

The reduction chemistry of cobalt complexes with HPNP (HPNP = HN(CH2CH2P(i)Pr2)2) as a supporting ligand is described. Reaction of [(HPNP)CoCl2] (1) with n-BuLi generated both the deprotonated Co(II) species [(PNP)CoCl] (2) along with the Co(I) complex [(HPNP)CoCl] (3). Products resulting from reduction of 2 with KC8 vary depending upon the atmosphere under which the reduction is performed.

Bimetallic ruthenium PNP pincer complex as a platform to model proposed intermediates in dinitrogen reduction to ammonia.

A series of ruthenium complexes was isolated and characterized in the course of reactions aimed at studying the reduction of hydrazine to ammonia in bimetallic systems. The diruthenium complex {[HPNPRu(N(2))](2)(μ-Cl)(2)}(BF(4))(2) (2) (HPNP = HN(CH(2)CH(2)P(i)Pr(2))(2)) reacted with 1 equiv of hydrazine to generate [(HPNPRu)(2)(μ(2)-H(2)NNH(2))(μ-Cl)(2)](BF(4))(2) (3) and with an excess of the reagent to form [HPNPRu(NH(3))(κ(2)-N(2)H(4))](BF(4))Cl (5). When phenylhydrazine was added to 2, the diazene species [(HPNPRu)(2)(μ(2)-HNNPh)(μ-Cl)(2)](BF(4))(2) (4) was obtained.

Metal complexes of Co, Ni and Cu with the pincer ligand HN(CH2CH2P(i)Pr2)2: preparation, characterization and electrochemistry.

A series of Co, Ni and Cu complexes with the ligand HN(CH(2)CH(2)P(i)Pr(2))(2) (HNP(2)) has been isolated and their electrochemical behaviour investigated by cyclic voltammetry. The nickel complexes [(HNP(2))NiOTf]OTf and [(HNP(2))NiNCCH(3)](BF(4))(2) display reversible reductions, as does the related amide derivative (NP(2))NiBr. The related copper(I) and cobalt(II) derivatives were also isolated and characterized.

(2,2-Bipyrid-yl)bis-(η-penta-methyl-cyclo-penta-dien-yl)strontium(II).

In the title compound, [Sr(C(10)H(15))(2)(C(10)H(8)N(2))], the Sr-N distances are 2.624 (3) and 2.676 (3) Å, the Sr⋯Cp ring centroid distances are 2.