Rhenium complexes pyridine

Analogous alkoxy and aryloxyrhenium complexes do not show the same reactivity. However, Brown and Mayer discovered soon thereafter that a different rhenium complex could mediate C—O bond formation.68 Photolysis of the Re(V) complex 13 led to C—H activation and formation of a phenyl rhenium oxo, 14. Yields were improved from 30-40% to 90% upon addition of pyridine to the photolysis mixture. The role of pyridine was unclear, because other tertiary amines provided no such improvement in yield. Substituted benzenes showed a preference for para activation over meta fluorobenzene also gave a significant amount of ortho activation. 

These -propargyl rhenium complexes undergo kinetic addition of nucleophiles at the central C atom to produce rhenacyclobutenes. The nucleophiles range from PR3 to malonate, acetylides, pyridines, and water. The derivatives of the addition of pyridines, however, are unstable and undergo further rearrangements to allene or acetylene complexes. Protonation of the metaUacyclobutenes produces u -allyl complexes. 

Oxo-rhenium complexes can catalyze various OAT reactions between suitable oxo-donors (XO = sulfoxides (R2SO) tertiary amine A-oxides (R3NO) pyridine A-oxide (C5H5NO, PyO) triphenyl-phosphine, -arsine, or -stilbene oxide (R3AO) (A = P, As, Sb) peroxides (Bn OOH, H2O2) ... 

Binuclear complexes of naphthalene (VIII) and of benzene (IX) with [Os(NH3)5]2+ and [Ru(NH3)5]2+ moieties were reported by Taube et al. (19), in which anti- //-1,2-rj2 3,4- 2) coordination of the arene is present. This bonding mode was first observed by Pasman et al. (20) in the binuclear Rhenium complex X. Wolczanski et al. (21) obtained complex XI from the mononuclear complex [Ta(0—Si Bu3)3 2-(N,C)-pyridine ] and benzene. Each tantalum atom is bound unsymmetrically to one C=C bond of benzene with a weak interaction to a third carbon atom the bonding may be described as a distorted tj3-enyl. In the dinuclear cobalt complex XII, the xylene functions as a bis(enyl)-ligand (12,22). 

NC2H7, Methaneamine, A -methyl-, molybdenum complex, 21 54 NC H , Pyridine, rhenium complex, 21 116, 117... 

SO are structurally and functionally very similar to SP. A series of rhenium complexes featuring a spironaphthoxazine-based pyridine ligand (SNOpy) [Re(CO)3(phen) (SNOpy)]-, [Re(CO>3(4,4 -Me2-bipy)(SNOpy)] and [Re(CO)3(4,4 - Bu2-bipy)... 

NC)H, l-Ptopanamine, intercalate with HNbTiOj, 22 89 NCJHii, l-Butanamine, intercalate with HNbTK), 22 89 NCjHs, Pyridine, cobalt complexes, 23 73 intercalate with FeCIO (1 4), 22 86 rhenium complex. 21 116, 117 NCsH , Butane, l-isocyano-, rhodium complex, 21 49... 

PF2HO2, Phosphorodifluoridic add, rhenium complex, 26 83 PF2N205ReC,3Hg, Rhenium, (2,2 -bi-pyridine)tricarbonyl(phosphorodi-iluoridatoK 26 83... 

Larger rhenium complexes are also the subject of a number of publications. Reaction of an excess of thietane with the thietane complex fRe3(CX))jQ(p-H)3(p-cyclo-SCH2CH2CH2)] affords a number of ring-opening oligomerisation products from which sulfur containing macrocycles such as 12-S-4, 16-S-4 and 24-S-6 can be eliminated upon addition of pyridine . Addition of... 

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