The preparation of 27 different derivatives of C60 and C70 fullerenes possessing various aryl (heteroaryl) and/or alkyl groups that are appended to the fullerene cage via a cyclopropane moiety and their use in bulk heterojunction polymer solar cells is reported. It is shown that even slight variations in the molecular structure of a compound can cause a significant change in its physical properties, in particular its solubility in organic solvents. Furthermore, the solubility of a fullerene derivative strongly affects the morphology of its composite with poly(3‐hexylthiophene), which is commonly used as active material in bulk heterojunction organic solar cells. As a consequence, the solar cell parameters strongly depend on the structure and the properties of the fullerene‐based material. The power conversion efficiencies for solar cells comprising these fullerene derivatives range from negligibly low (0.02%) to considerably high (4.1%) values. The analysis of extensive sets of experimental data reveals a general dependence of all solar cell parameters on the solubility of the fullerene derivative used as acceptor component in the photoactive layer of an organic solar cell. It is concluded that the best material combinations are those where donor and acceptor components are of similar and sufficiently high solubility in the solvent used for the deposition of the active layer.

Novel bis(phosphine) pincer complexes of iridium based on ferrocene and ruthenocene have been synthesized. The reaction of 1,3-bis((di-tert-butylphosphino)methyl)metallocenes [t-BuP,CH,PM] (M = Fe, 10; M = Ru, 13) with [Ir(COE)2Cl]2 in refluxing toluene leads to the corresponding chloro-hydrido pincer complexes as a mixture of H-endo- (M = Fe, 11; M = Ru, 14) and H-exo-IrH(Cl)[t-BuP,C,PM] (M = Fe, 12; M = Ru, 15) isomers. Treatment of compounds 11, 12 and 14, 15 with NaH in hot cyclooctane generates corresponding dihydrido complexes IrH2[t-BuP,C,PM] (M = Fe, 6; M = Ru, 7). Reactivity of the chelated iridium atom in hydrido-iridium pincer complexes and oxidation centered at the iron atom of ferrocene-based pincer complexes were studied. Complexes H-exo-IrH(Cl)(CO)[t-BuP,C,PFe] (20), Ir(CO)[t-BuP,C,PFe] (21), and Ir(CO)[2,6-(tBu2PO)2C6H3] (30) were characterized by X-ray crystallography. On the basis of νCO values for carbonyl iridium derivatives, electronic characteristics of the corresponding fragments {Ir[t-BuP,C,PM]} n (n = 0, +1) were elucidated. Complexes 6 and 7 reveal unprecedented catalytic activity in cyclooctane dehydrogenation in the presence of tert-butylethylene as a hydrogen acceptor:  turnover numbers 3300, 2571, and 1843 were obtained for 6, 7, and the known complex IrH2[2,6-(tBu2PO)2C6H3] (4c), respectively, at 180 °C for 8 h. The high catalytic activity for 6 and 7 and the difference in the catalytic activity of these “isostructural” complexes are discussed in terms of steric and electronic effects.

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Keywords: Asymmetric catalysis / Cyanohydrins / Titanium / AldehydesTitanium complexes 1 derived from chiral salen ligands are highly active precatalysts for the asymmetric addition of trimethylsilyl cyanide to aldehydes and ketones. Based on spectroscopic studies and the identification of adducts between complexes 1 and carbonyl compounds or trimethylsilyl Scheme 1 [a]

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We report for the first time the application of chlorofullerene C60Cl6 as a substrate for straightforward preparation of highly water-soluble fullerene derivatives, promising compounds for investigation of the biological action of fullerenes in vitro and in vivo. Methyl esters of phenylacetic and benzylmalonic acids were used as reagents in the Friedel-Crafts arylation of C60Cl6 that resulted in the corresponding C60(Ar)5Cl compounds with 50-60% yields. The following cleavage of ester groups in phenylacetic and benzylmalonic residues was accomplished almost quantitatively to yield the corresponding fullerene-based acids bearing 5 and 10 carboxylic groups, respectively. The relatively-low solubility of these acids in water can be strongly enhanced (up to 150-200 mg ml(-1)) by their conversion to salts with alkali metal cations. These fullerene salt derivatives showed pronounced anti-HIV action and low toxicity; these two findings point to the necessity for further investigation of the biological properties of the here-reported compounds.

Tuberculosis is one of the most common infectious diseases known to man. About 37% of the world's population (about 1.86 billion people) are infected with Mycobacterium tuberculosis. According to the World Health Organization, every year approximately 8 million people develop active tuberculosis and almost 2 million of those die from the disease. The incidence of multidrug-resistant tuberculosis (MDR-TB) is increasing. The present drug regimen for treating tuberculosis has been in existence for 30 years. New drugs that will shorten total treatment duration, improve the treatment of MDR-TB, and address latent tuberculosis are the most urgent need of tuberculosis control programs. A new series of synthetic 3-amino-4-arylpyridazino[4,3-b]indoles (pyridazinoindoles) were identified as inhibitors of Mycobacterium tuberculosis. The design, synthesis, and antimycobacterial activity of these compounds are described. While the most active compounds are still not comparable to the front-line drugs rifampicin and isoniazid, they do show promise. Most of the pyridazinoindoles with appreciable antituberculosis activity also inhibit monoamine oxidase, suggestive of a novel inhibitory effect on mycobacterial redox reactions.

Palladium P,C,P pincer complexes based on ferrocene were synthesized for the first time. The reaction of 1,3-bis(dialkylphosphinomethyl)ferrocenes {1,3-(R2PCH2)2C5H3}Fe(C5H5) (2a, R=Pr i ; 2b, R=Bu t ) with PdCl2(NCPh)2 in refluxing 2methoxyethanol leads to the corresponding pincer complexes PdCl[{2,5-(R2PCH2)2C5H2}Fe(C5H5)] (3a, 3b). Ferrocene-based binuclear compound 3b reacts with [Cp2Fe]PF6 to form the ferrocenium-based pincer complex {PdCl[{2,5-(Bu t 2PCH2)2C5H2}Fe(C5H5)]}PF6 (4b), and this is the first example of ferrocene-based phosphine chelate oxidation centered on the iron atom. Treatment of complexes 3a and 3b with NaBH4 in refluxing ethanol leads to the complexes Pd(BH4)[{2.5-(R2PCH2)2C5H2}Fe(C5H5)] (5a, R=Pr i ; 5b, R=Bu t ), containing a BH4  group coordinated to the metal in the rarely occurring unidentate mode. The structures of 3a, 3b, and 5b were confirmed by X-ray analyses. Cyclic voltammetric investigations of complexes 2a, 2b, 3a, and 3b are also reported. The structural and spectroscopic features of the palladium ferrocene-based pincer complexes are discussed and compared with those of related compounds.