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Manganese, arene complexes

Organozinc reagents can also be added to the cationic manganese arene complexes. Neutral jj -l-chlorocyclohexadienyl... [Pg.3244]

The reactions of (arene)Cr(CO)j, (arene)Mn(CO)j and [(arene)MCp] (M = Fe or Ru) complexes have been studied extensively. Many of these arene compoimds have been prepared by heating the arene with Cr(CO)y but because dissociations of amines, nitriles or arenes from Cr(0) fragments are typically faster than dissociation of CO (see Chapter 5), reactions of arenes with Cr(CO)j(L)3 (L = NH or NCMej) or with (naphthalene) Cr(CO)j are milder than reactions with Cr(CO). Manganese-arene complexes [(arene) Mn(CO)3] - are typically generated from (CO)5MnBr, AgBF and arene, while the iron-and ruthenium-arene complexes [(arene)MCp] are typically generated by addition of arenes to [CpM(NCMe)3] (M = Fe or Ru). " ... [Pg.443]

Examples of reductive cluster-opening and oxidative cluster-closing reactions are common in the chemistry of metal-hydrocarbon tt complexes. For example, bases convert nido- (hexa-hapto)arene-manganese tricarbonyl complexes into aracAno(pentahapto)-7T-cyclohexadienyl complexes 129,130, 217) ... [Pg.48]

Manganese, iron, cobalt, and nickel vapors do not give arene complexes with haloarenes. Interactions with hexafluorobenzene have been reported, but the explosive products are unlikely to be complexes containing planar C8F8 rings. The Ni-C8F8 cocondensate is a source of... [Pg.75]

Manganese allyl complexes, preparation, 5, 826 Manganese arenes, preparation and characteristics, 5, 830 Manganese aryl complexes, preparation and characteristics,... [Pg.138]

Manganese carbenes, preparation, 5, 825 Manganese carbonyl complexes with 776-arene complexes, 5, 787 cyclopentadienyl complexes, 5, 783 with hydrocarbon ligands, complexes, 5, 776 synthesis and characteristics, 5, 761 Manganese carbonyl halides, applications and reactivity,... [Pg.138]

Similar iron sandwich [Fe(t -C5H5)(ri-arene)] PF6] [730,731] and manganese-arene [(r -arene)(CO)3Mn][PF6] [731] complexes were isolated and characterized. The... [Pg.284]

A variety of transition metals, for example, chromium, molybdenum, tungsten, iron, vanadium, manganese, and rhodium can be used to prepare relatively stable j -arene complexes (see Arene Complexes). Reactions of j -arene chromium tricarbonyl complexes have been extensively examined, and numerous reviews are available. Although chromium complexes are by far the most utilized in organic synthesis, complexes of iron and manganese are emerging as potentially useful alternatives. [Pg.3235]

The advantage of using lithiated arene complexes of chromium as starting materials to synthesize o-,7r-bimetallic complexes of chromium and manganese was clearly demonstrated by reacting (77 -o-C6H4XLi)Cr(CO)3 (X = H, F) with Mn(CO),Br (305). The products, (77< -C6H4XC(0) Mn-... [Pg.293]

Chlorination. Activated arenes are chlorinated with (salen)manganese(III) complex, and moist alumina in dichloromethane. [Pg.348]

Transition metal organometallic complexes like dicarbonyl cyclopentadienyl iron [128], tricarbonyl cyclopentadienyl manganese [129] and iron-arene complexes [130,131] have also been reported as photoinitiators for photochemical crosslinking of cyanate esters. Photosubstitution of carbonyl groups by -OCN during irradiation initiates the reaction in the former case whereas photochemical dissociation of arene triggers it in the latter system. [Pg.30]

In a new and significant development, it was found that chlorocyclohexadienyl manganese tricarbonyl complexes undergo palladium-catalyzed coupling reactions with a variety of carbon nucleophiles to afford products from which hydride may be abstracted with trityl cation, thus generating new [( -arene)Mn(CO)3]+ complexes containing substituents that cannot be introduced in any other manner. This is particularly true of electron-withdrawing substituents. Scheme 16 illustrates the chemistry involved. [Pg.2527]

Keywords Arene complexes Chromium Molybdenmn Manganese Iron Ruthenium... [Pg.3]

Scheme Cationic arene manganese tricarbonyl complexes prepared from the [Mn(CO)5] fragment. [Mn(CO)5] is generated in situ via Method A Mn(CO)5Br (58)/AlCl3/A Method B Mn2(CO)io/TFA/TFA-anhydride/reflux Method C Complex 58/AgBF4/CH2Cl2/reflux. In all cases the counteranion is either BF4" or PFg"... Scheme Cationic arene manganese tricarbonyl complexes prepared from the [Mn(CO)5] fragment. [Mn(CO)5] is generated in situ via Method A Mn(CO)5Br (58)/AlCl3/A Method B Mn2(CO)io/TFA/TFA-anhydride/reflux Method C Complex 58/AgBF4/CH2Cl2/reflux. In all cases the counteranion is either BF4" or PFg"...
This method may be utilized for the preparation of most arene sandwich compounds as well as for many other arene complexes. However, it cannot be used for manganese arene derivatives. [Pg.590]

A wide range of metals form ti -arene complexes, but the best-known complexes are with chromium tricarbonyl. Complexes of iron, manganese and ruthenium have also been used. These complexes have the Cr(CO)3 moiety or other metallic fragment above the -ir-system of the aromatic ring (Figures 10.2 and 10.3), thereby making the two faces distinct. This can be exploited for stereochemical control purposes. [Pg.377]

Most arene complexes are hexahapto, and ternary complexes usually have 18 valence electrons. The most known and used ones for their applications in arene synthesis are the arene-metal-tricarbonyls (columns of chromium and manganese), in particular the arene-chromium-tricarbonyl and the arene-manganese-tricarbonyl cations... [Pg.243]


See other pages where Manganese, arene complexes is mentioned: [Pg.3244]    [Pg.3243]    [Pg.3244]    [Pg.3243]    [Pg.250]    [Pg.170]    [Pg.1122]    [Pg.60]    [Pg.122]    [Pg.158]    [Pg.372]    [Pg.235]    [Pg.2528]    [Pg.220]    [Pg.219]    [Pg.92]    [Pg.310]    [Pg.219]    [Pg.115]    [Pg.188]    [Pg.90]    [Pg.381]    [Pg.462]    [Pg.167]    [Pg.126]    [Pg.451]    [Pg.85]    [Pg.86]    [Pg.169]    [Pg.206]   
See also in sourсe #XX -- [ Pg.65 , Pg.78 , Pg.90 ]




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Manganese complexes

Manganese complexing

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