Manganese complexes bromides

Manganese pentacarbonyl bromide reacts with Na[PhNNNPh] (118), ArNNNAr-SiMc3 (1), or ArNNNAr-SnMe3 (1) to generate the chelate complexes Mn(ArNNNAr)(CO)4, which in turn readily lose a carbonyl ligand to form monosubstituted products Mn(ArNNNAr)(CO)3L (L = PPhj, PMe2Ph, and AsPhj) (1). 

The active catalysts seem not to be free cobalt, manganese, or bromide species, but complexes like Co(OAc)Br or Mn(OAc)Br which act additionally as important chain carriers. At higher temperatures the activity of the metal/ bromide systems increases [16]. 

Photolysis of diethylthallium bromide in cyclohexane is a radical process involving cleavage of the thallium-carbon bond, which yields ethylcyclohexane and dicyclohexyl, as well as other products. Photoelectron transfer from benzyltributylstannanes to 10-methylacridinium ion results in cleavage of the metal-carbon bond, to give the corresponding benzyl radicals, rather than benzyl cations. Photochemical homolysis of Re- and Ru-alkyl bonds in Re(alkyl)-(CO)3(diimine) and Ru(I)(alkyl)(CO)2(diimine) complexes has been studied by Fourier transform ESR. In related manganese complexes, Mn(R)(CO)3(di-imine), elimination of CO is the predominant pathway when R = methyl, but Mn-alkyl homolysis occurs when R = benzyl. 

A manganese complex formed from a solution containing potassium bromide and oxalate ion is purified and analyzed. It contains 10.0% Mn, 28.6% potassium, 8.8% carbon, and 29.2% bromine by mass. The remainder of the compound is oxygen. An aqueous solution of the complex has about the same electrical conductivity as an equimolar solution of K4[Fe(CN)g]. Write the formula of the compound, using brackets to denote the manganese and its coordination sphere. 

Desymmetrization of a meso-intermediate also held the key to enantio-selectivity in the approach to (—)-swainsonine (378) by Katsuki and his colleagues (Scheme 70). In this case, the (R,R)-(salen)manganese complex 524 mediated the enantioselective oxidation of the meso-pyrrolidine 525 with iodosylbenzene to the (2S)-hydroxypyrrolidine 526, which was further oxidized with pyridinium chlorochromate to yield lactam (—)-527 in an overall yield of 56% and an ee of 71%. Reaction with 4-chlorobutylmagne-sium bromide opened the lactam ring to give the chloroketone (+)-528, which underwent spontaneous cyclization to the cyclic imine 529 upon... 

Further studies on the formation of glycosyl manganese complexes (V0I.I9, p.29-30, 161) has shown that both the yield and stereoselectivity of the reaction is affected by adding bromide ion to the reaction mixture (Scheme 2). ... 

Rubidium metal alloys with the other alkaU metals, the alkaline-earth metals, antimony, bismuth, gold, and mercury. Rubidium forms double haUde salts with antimony, bismuth, cadmium, cobalt, copper, iron, lead, manganese, mercury, nickel, thorium, and 2iac. These complexes are generally water iasoluble and not hygroscopic. The soluble mbidium compounds are acetate, bromide, carbonate, chloride, chromate, fluoride, formate, hydroxide, iodide. 

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... 

There are few reports of oxidative addition to zerovalent transition metals under mild conditions three reports involving group 10 elements have appeared. Fischer and Burger reported the preparation of aTT -allylpalladium complex by the reaction of palladium sponge with allyl bromide(63). The Grignard-type addition of allyl halides to aldehydes has been carried out by reacting allylic halides with cobalt or nickel metal prepared by reduction of cobalt or nickel halides with manganese/iron alloy-thiourea(64). 

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... 

We have not been able to unscramble the complex kinetics of p-xylene oxidation. Ravens studied the second stage of oxidation, that of p-toluic acid in acetic acid with cobalt and manganese acetates and sodium bromide (25), and established the rate equation... 

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