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Manganese complexes, cation, with

The most important low-spin octahedral complex of Mn is the dark-red cyano complex, [Mn(CN)6] , which is produced when air is bubbled through an aqueous solution of Mn and CN . [MnXs] (X = F, Cl) are also known the chloro ion, at least when combined with the cation [bipyH2] +, is notable as an example of a square pyramidal manganese complex. [Pg.1057]

The catalytic application of clays is related closely to their swelling properties. Appropriate swelling enables the reactant to enter the interlamellar region. The ion exchange is usually performed in aquatic media because the swelling of clays in organic solvents, and thus the expansion of the interlayer space, is limited and it makes it difficult for a bulky metal complex to penetrate between the layers. Nonaqueous intercalation of montmorillonite with a water-sensitive multinuclear manganese complex was achieved, however, with the use of nitromethane as solvent.139 The complex cation is intercalated parallel to the sheets. [Pg.259]

Neutral (cyclohexadienyl)manganese complexes 71, generated by nucleophilic addition to (arene)Mn(CO)3+ cations 65, undergo ligand substitution with nitrosyl hexafluorophosphate to give the corresponding (cyclohexadienyl)Mn(CO)2NO+ cations 72 (Scheme 17)93. Attack by a wide variety of nucleophiles on cations 72... [Pg.915]

An electrospray mass spectrometric study of the interaction of manganese(II) salts with the tetrathia analogue of cyclam showed the utility of this technique for detecting complex formation for both manganese and a series of other metal cations. [Pg.78]

Using this method, the electrophilic aromatic substitution of the electron-rich arylamine 578 by the molybdenum-complexed cation 577 affords regio- and stereoselectively the molybdenum complexes 579. Cyclization with concomitant aromatization and demetalation using activated manganese dioxide leads to the carbazole derivatives 568 (8,10,560) (Scheme 5.26). [Pg.208]

Electrophilic aromatic substitution of 708 with the iron-coordinated cation 602 afforded the iron-complex 714 quantitatively. The iron-mediated quinone imine cyclization of complex 714, by sequential application of two, differently activated, manganese dioxide reagents, provided the iron-coordinated 4b,8a-dihydrocarbazole-3-one 716. Demetalation of the iron complex 716 with concomitant... [Pg.233]

The total synthesis of carbazomycin D (263) was completed using the quinone imine cyclization route as described for the total synthesis of carbazomycin A (261) (see Scheme 5.86). Electrophilic substitution of the arylamine 780a by reaction with the complex salt 779 provided the iron complex 800. Using different grades of manganese dioxide, the oxidative cyclization of complex 800 was achieved in a two-step sequence to afford the tricarbonyliron complexes 801 (38%) and 802 (4%). By a subsequent proton-catalyzed isomerization, the 8-methoxy isomer 802 could be quantitatively transformed to the 6-methoxy isomer 801 due to the regio-directing effect of the 2-methoxy substituent of the intermediate cyclohexadienyl cation. Demetalation of complex 801 with trimethylamine N-oxide, followed by O-methylation of the intermediate 3-hydroxycarbazole derivative, provided carbazomycin D (263) (five steps and 23% overall yield based on 779) (611) (Scheme 5.91). [Pg.250]

The synthesis of the Y zeolite-encapsulated manganese complex of the salen ligand has been reported recently [51]. It was found to have catalytic activity in the oxidation of cyclohexene, styrene, and stilbene with PhlO. Typically, 1 Mn(salen) is present per 15 supercages, resulting in catalytic turn-overs in the order of 60. The reactions investigated with the respective product yields are given in Scheme 5. Typical oxidation products are epoxides, alcohols and aldehydes. In comparison to the homogeneous case encapsulation seems to lower the reaction rate. From cyclohexene the expected oxidation product cyclohexene oxide is present in excess and is formed on the Mn(salen) site. 2-cyclohexene-l-ol is probably formed on residual Mn cations via a radical mechanism. [Pg.243]

Brunner has continued his studies on optically active manganese carbonyl complexes and has reported that treatment of Mn(CO)5Br with ort/to-Me2NC6H4PPh2 (PN) yields two enantiomers of/ac-[Mn(CO)3(PN)Br], Treatment of this complex with carbon monoxide in the presence of A1C13 produces the cation [Mn(CO)4(PN)] +, which was isolated as its hexafluorophosphated salt. Addition of menthoxide anions to the manganese carbonyl cation yields the diastereoisomers of Mn(CO)3(PN) (CO2C30H 9) however, these could not be separated due to their instability. Reaction of Mn(CO)5Br with the Schiff base NN (1) leads to formation of two isomers of... [Pg.164]


See other pages where Manganese complexes, cation, with is mentioned: [Pg.87]    [Pg.219]    [Pg.219]    [Pg.83]    [Pg.994]    [Pg.55]    [Pg.43]    [Pg.220]    [Pg.6]    [Pg.67]    [Pg.74]    [Pg.35]    [Pg.212]    [Pg.141]    [Pg.282]    [Pg.761]    [Pg.241]    [Pg.1052]    [Pg.80]    [Pg.23]    [Pg.158]    [Pg.108]    [Pg.1288]    [Pg.15]    [Pg.61]    [Pg.85]    [Pg.134]    [Pg.146]    [Pg.6]    [Pg.273]    [Pg.320]    [Pg.103]    [Pg.790]    [Pg.84]    [Pg.773]    [Pg.1288]   


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Cations with

Manganese complexes

Manganese complexes, cation

Manganese complexes, cation nonelectrolyte, with pyridine and

Manganese complexes, with

Manganese complexing

With manganese

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