Lithium-benzene complexes

The synthesis of the zero-valent, 1,3-cyclohexadiene benzene ruthenium complex 196a has been mentioned as a coproduct of the cyclohexadienyl complex 236a in the reduction of the benzene ruthenium dication 235 with lithium aluminum hydride. Reduction of 235 with sodium borohydride in THF, however, gives only the air-sensitive, yellow-green ruthenium(O) complex 196a (118). This reaction has been generalized to... 

The lithiated derivative (LiCgH5)Cr(CO)3 has been prepared in high yield by the reaction of [(CO)3Cr](CaHgHgC6H5)[Cr(CO)3] with re-butyl lithium. Complexes, such as 2-phenylpyridine chromium tricarbonyl and (Ph2PCgHg)Cr(CO)3, which are not otherwise obtainable were prepared by the reaction of the lithiated derivative with pyridine and PhaPCl, respectively 348). Benzene chromium tricarbonyl has been metalated by treatment with re-butyl lithium in THF and after carbona-tion yielded w-benzoic acid chromium tricarbonyl 304). 

C,H,N, Benzene, 2-isocyano-l,3-dimethyl-, iron complexes, 26 53 57 C,H jN, Benzenemethanamine, N,N-di-methyl-, lithium complex, 26 152 Iutetium complex, 27 153 palladium complex, 26 212 QHijP, Phosphine, cthylmethylphenyl-, lithium complex, 27 178 C,H,3P, Phosphorane, dimethylmethylene-diphenyl-, uranium complex, 27 177 C,H P, Phosphine, triisopropyl-, rhodium complex, 27 292 tungsten complex, 27 7 C,Hj7PSi3, Phosphine, tris(trimethylsilyl)-, 27 243... 

C12H111N2, Azobenzene, cobalt and palladium complexes, 26 175, 176 manganese complex, 26 173 C12H11N, Pyridine, 2-(phenylmethyl)-, palladium complex, 26 208-210 C12H11P, Phosphine, diphenyl-, manganese complex, 26 158, 226-230 ruthenium complex, 26 264 Ci2H,20,S, Thiophenetetracarboxylic acid, tetramethyl ester, 26 166 C 2H,5N, Naphthalenamine, A ,iV-dimethyl-, lithium complex, 26 154 Cj2Hih, Benzene, hexamethyl-, ruthenium complex, 26 181, 182... 

SiCijH , Benzene, 1,2-bis[(trimethylsilyl)-methyl]-, lithium complex, 26 148 Si HKnOjiiVjWv 3H 0, 1,2,3-Trivanadonona-tungstosilicate(7-), A-p-, hexapotas-sium hydrogen, trihydrate, 27 129 SiHNa,0.v4W,23H2ih Nonatungstosilicate-(10-), p-, nonasodium hydrogen, tri-cosahydrate, 27 88... 

It has been recognized for many years that nucleophiles will add to q -benzene-FeCp" complexes. Reactive nucleophiles such as cyanide, hydride [123],methyl-, and phenyl lithium [2] add to unactivated (arene)FeCp complexes, whereas less reactive nucleophiles such as phenyl acetylide, lithium salts of acetonitrile, nitromethane and ketones [84,124] require an electron-withdrawing group to be present on the arene ring of the complex. On the other hand, cyanide or an anion derived from propionitrile added to several unactivated arene complexes [67,76,123-126]. 

Fig. 2 Space filling representation of a receptor comprised of (benzene)Ru complexes and the ligand L3 with a sodium ion (left) or a lithium ion (right) in the binding pocket. Larger cations do not bind to the receptor because they are efficiently blocked by the arene 7r-ligands...

SiCigHjg, Benzene, l,2-bis[(trimethyl-silyl)methyl]-, lithium complex,... 

Si2C,H22,13-Cylithium complexes, 27 170 Si2C,4H2t, Benzene, 1,2-... 

The polarity of the Li—C bond is so much increased by co-ordination with TMED that the TMED n-butyl-lithium complex adds ethylene under moderate pressure giving polymers. Reaction in the presence of benzene gives phenyl-ended telomers ... 

Ethereal methyl1ithiurn (as the lithium bromide complex) was obtained by the submitters from Aldrich Chemical Company Inc. The checkers used 1.19 M methyl1ithiurn-lithium bromide complex in ether supplied by Alfa Products, Morton/Thiokol, Inc. The concentration of the methyllithium was determined by titration with 1.0 M tert-butyl alcohol in benzene using 1,10-phenanthroline as indicator. The submitters report that ethereal methyllithium of low halide content purchased from Alfa Products, Morton/Thiokol, Inc., gave similar results. 

In preparation of di-//-mcthylcncbis(incthyl-pcntamcthylcyclopcntadicnvl)dirhod-ium complexes by aerobic oxidation of a solution of the halocomplex and methyl-lithium or trimethylaluminium in ether-benzene, the reaction mixture occasionally ignited and burned violently. Full precautions and a working scale below 1 mmol are recommended. 

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