Complexes of manganese

The complexes of manganese(III) include [Mn(CN)g] (formed when manganesefll) salts are oxidised in presence of cyanide ions), and [Mnp5(H20)] , formed when a manganese(II) salt is oxidised by a manganate(VII) in presence of hydrofluoric acid ... 

The field of oxo-bridged polynuclear complexes of manganese, much of it involving mixed... 

Complexes of manganese with the 1,1-dithiolates have been restricted to the (PrSN)3[Mn(i-mnt)3] complex (112) and nitrosyl or carbonyl derivatives, e.g., [7i--CpMn(NO)(S2C==X)] (X = C(CN)C02Et, C(CN)C0NH2, NCN, C(CN)2, or (HNO2) (110, 204, 205). These complexes undergo electrochemical, one-electron oxidations and reductions to afford the neutral or dianionic species. 

In a similar approach, double deprotonation of r 6-coordinated ortho- and para-cresols, 30 and 31, with t-BuOK led to formation of stable r 4-coordinated p- and o-quinone methide complexes of manganese, 32 and 33 (Scheme 3.19).37... 

A PRP -1 (Hamilton Reno, NV) reversed phase column was coated with cetylpyridinium and eluted with tetramethylammonium salicylate acetoni-trile water.89 The separation was comparable to that observed on conventional ion exchange. Coated phases were also used to separate oxalate complexes of manganese, cobalt, copper, and zinc.90 Reversed phase silica supports were coated with poly(N-ethyl-4-vinylpyridinium bromide), poly(dimethydiallylammonium chloride), poly(hexamethyleneguanidinium... 

When propylene chemisorbs to form this symmetric allylic species, the double-bond frequency occurs at 1545 cm-1, a value 107 cm-1 lower than that found for gaseous propylene hence, by the usual criteria, the propylene is 7r-bonded to the surface. For such a surface ir-allyl there should be gross similarities to known ir-allyl complexes of transition metals. Data for allyl complexes of manganese carbonyls (SI) show that for the cr-allyl species the double-bond frequency occurs at about 1620 cm-1 formation of the x-allyl species causes a much larger double-bond frequency shift to 1505 cm-1. The shift observed for adsorbed propylene is far too large to involve a simple o--complex, but is somewhat less than that observed for transition metal r-allyls. Since simple -complexes show a correlation of bond strength to double-bond frequency shift, it seems reasonable to suppose that the smaller shift observed for surface x-allyls implies a weaker bonding than that found for transition metal complexes. 

The porphyrin complexes of manganese exist in a range of formal oxidation states of which the +3 state is most stable. Mn(m) porphyrins may be electrochemically oxidized in non-aqueous media to yield products which are probably Mn(m) cation radicals or di-cations (Kelly Kadish, 1982). The potentials at which these reactions occur are sensitive... 

Donor-stabilized silylene complexes of manganese include 45 and 46, which have been prepared by the reaction of the corresponding R2SiH2 or RSiH3 compound with (77S-CsH4R)Mn(CO)3 (R = H, Me).71 128... 

In a similar manner, Jt-allyl complexes of manganese, iron, and molybdenum carbonyls have been obtained from the corresponding metal carbonyl halides [5], In the case of the reaction of dicarbonyl(r 5-cyclopentadienyl)molybdenum bromide with allyl bromide, the c-allyl derivative is obtained in 75% yield in dichloromethane, but the Jt-allyl complex is the sole product (95%), when the reaction is conducted in a watenbenzene two-phase system. Similar solvent effects are observed in the corresponding reaction of the iron compound. As with the cobalt tetracarbonyl anion, it is... 

Farona and Kraus have postulated the existence of both a- and rr-bonded dinitrile complexes of manganese carbonyl halides and suggest that the monomeric jr-complexes are the kinetically favoured species, whereas the CT-bonded complexes are thermodynamically favoured. ... 

Other aza-donor macrocyclic ligand complexes of manganese(II) have been synthesized using metal template procedures." ... 

Recently, isolable bis (triphenylstannyl)-substituted butatrienylidene complexes of manganese (13) were obtained by photolysis of alkynyl(triphenylstannyl)vinylidene complexes 12 (Scheme 3.9) [4, 5]. Treatment of the resulting bis(stannyl)butatrie-nylidene complexes 13 with tetrabutylammonium fluoride and water afforded the first characterizable butatrienylidene complexes (14) containing an unsubstituted [M=C=C=C=CH2] moiety (Scheme 3.9). In contrast to 13, complexes 14 were unstable above —5 °C and were therefore characterized in solution only by NMR spectroscopy at —40°C. Complexes 14 were also formed instantaneously when solutions of 12 were treated at — 30 °C with one equivalent of tetrabutylammonium fluoride. 

The peroxynitrito complexes derived from Craq002+ and L2(H20)Rh002 + are short lived and in that sense reminiscent of the peroxynitrites of hemoglobin (182,201), myoglobin (182), and porphyrin complexes of manganese (183,184) and iron (171,180), and different from another inorganic ion, (CN)5CoOON03, which is extremely stable (202). 

The complexes [M(CO)5(> 2-C2H4)] [A1C14] (M = Mn, Re) were first prepared by abstraction of the chloride ligand in M(CO)sCl using aluminum-trichloride under ethylene pressure.14 The preparation of [BF4] salts of these cationic pentacarbonylethene complexes of manganese and rhenium proceeds under very mild conditions (1 bar) and gives high yields.6... 

A. Synthesis and Physical Properties of q6-OFCOT and tj6-COT Complexes of Manganese... 

A number of studies of phthalocyanine and porphyrin complexes of manganese have been carried out and it is clear that both MnIn and MnlV complexes can be photoreduced in the presence of water or OH- and in the absence of an electron acceptor.309 313 These complexes can be produced from Mn11 or Mnm complexes in the presence of an electron acceptor e.g. quinones,314 and the reaction can be sensitized by, for example, zinc porphyrins in suitable model membrane environments.310... 

Both the square planar bis(acetylacetonato)manganese(II) and the octahedral tris(acetyl-acetonato)manganese(III) have been shown to possess marked fungicidal activity in the protection of cotton and linen.49 Recently, the complex of manganese(II) with 4-(5 -phenyl-l, 3, 4 -oxadiazol-2 -yl)thiosemicarbazide (14) has also been shown to exhibit fungicidal properties.50 The structure of this bis-complex also appears to be unknown at present. 

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