SUBJECTS amine complexes

The bacterial resistance of silk fibroin can be improved by treatment at low pH values in aqueous solutions of metal ions and at high pH values in solutions of metal-amine complexes, using untreated silk or silk pretreated with an aqueous solution of tannic acid (10.183). Suitable metals include Cu, Zn, Ni, Fe and Ag [533]. It is to be expected that treatment with such metal compounds will be subject to restrictions in environmentally sensitive areas. 

Photoactivation of Mg(amine)+ complexes has been the subject of several studies. The photofragmentation pathways are dependent on the structure of the amine. For... 

Subsequently, we examined several MFA derivatives as substrates for the Pt/C>2 reaction. When 32 was subjected to Pt/(>2 chemistry, three products (132-134) were isolated in poor yield [Fig. (36)]. In the case of 23, the Pt/C>2 reaction mixture was treated straightaway with m-CPBA without isolation of any intermediate products, giving the desired compound 10 (43% yield). Compound 10 can be converted to PHA (2) in three steps. Compound 132 was converted to PHA (2) by treatment with alane-dimethylethyl amine complex in THF (30% yield). 

Certain octahedral complexes, particularly the acido—amine complexes of cobalt(III), undergo substitution in protonic solvents at rates that are proportional to the concentration of the conjugate base of the solvent (e.g. OH- in water) or inversely proportional to the concentration of the conjugate acid of the solvent (e.g. retardation by H30+ in water or NH4+ in liquid ammonia). Such reactions have received considerable attention since systematic studies of ligand substitution commenced, and figured amongst the earliest kinetic studies in the field.298 The subject has been... 

Metal template syntheses of complexes incorporating the p-amino imine fragment have been introduced by Curtis as a result of his discovery that tris(l,2-diaminoethane)nickel(II) perchlorate reacted slowly with acetone to yield the macrocyclic complexes (40) and (41) (equation 8).81-83 In this macrocyclic structure the bridging group is diacetone amine imine, arising from the aldol condensation of two acetone molecules. This reaction is widely general, in the same way that the aldol reaction is, and can be applied to many types of amine complexes. The subject has been reviewed in detail with respect to macrocyclic complexes by Curtis.84... 

In principle, the photoreactions of CT s are able to offer a great number of photoinitiator systems for radical polymerization. But, so far, this subject has only received little attention, and the current knowledge relative to the photochemistry of such complexes is poor. In addition to the amine complexes mentioned above, chinoline-bromine [124-127], chinoline-chlorine [128], 2-methylpyridine-chlorine [129], pyridine-bromine [130], IV-vinylpyrrolidone-bromine [131], acridone-bro-mine [132], acridone-chlorine [133], benzophenone-S02 [134], isoquinoline-S02 [135, 136], and 2-methylquinoline-S02 [136] combinations are used for radical polymerization of AN, alkyl methacrylates, acrylic and methacrylic acid, and for... 

Crystalline 2,6-DHN 1 (or its amine-complex) and FeCl3 6H20 (300 mol% for 2,6-DHN) were mixed well with an agate mortar and pestle. The black mixture was kept at room temperature or heated at 50 °C, and the reaction was monitored by TLC. An aqueous Na2S03 solution was added to stop the reaction. The precipitate, poly(2,6-dihydroxy-l,5-naphthylene) 2, was washed several times with 1 M aqueous HC1 and then water. The dark green polymer obtained was dried under vacuum and subjected to acetylation without further purification. 

The symmetric ions [Co(CN)g] or [Co(am)6] (where am = NHj or half a chelating diamine) should have very small efg and have been the subjects of several relaxation studies. For the amine complexes (and [Co(N02)6] there are significant contributions to from scalar coupling to N. The temperature dependence of for [Co(NH3)6] suggests that spin-rotation may compete with... 

Addition of several organomercury compounds (methyl, aryl, and benzyl) to conjugated dienes in the presence of Pd(II) salts generates the ir-allylpalladium complex 422, which is subjected to further transformations. A secondary amine reacts to give the tertiary allylic amine 423 in a modest yield along with diene 424 and reduced product 425[382,383]. Even the unconjugated diene 426 is converted into the 7r-allyllic palladium complex 427 by the reaction of PhHgCI via the elimination and reverse readdition of H—Pd—Cl[383]. 

Like mthenium, amines coordinated to osmium in higher oxidation states such as Os(IV) ate readily deprotonated, as in [Os(en) (NHCH2CH2NH2)] [111614-75-6], This complex is subject to oxidative dehydrogenation to form an imine complex (105). An unusual Os(IV) hydride, [OsH2(en)2] [57345-94-5] has been isolated and characterized. The complexes of aromatic heterocycHc amines such as pyridine, bipytidine, phenanthroline, and terpyridine ate similar to those of mthenium. Examples include [Os(bipy )3 [23648-06-8], [Os(bipy)2acac] [47691-08-7],... 

In the reaction of amines such as NH3, NH2NH2, MeNH2, C6HUCH2NH2, and Ph(OMe)NH2, only monosubstitution can be obtained even in the presence of a large excess of the amine. This is taken into account by the deprotonation of the acidic monosubstituted complex by free amine leading to an iminocyclohexadienyl complex. The latter cannot be subjected to nucleophilic substitution of the second... 

As a result the research emphasis in this field focused on efforts to design experiments in which it might be possible to determine to which one of the foregoing three rate equations the observed second-order rate coefficient actually corresponded. More specifically, the objective was to observe one and the same system first under conditions in which complex decomposition (fcp) was rate-determining and then under conditions in which complex formation (kF) was ratedetermining. A system in which either formation or decomposition was subject to some form of catalysis was thus indicated. In displacements with primary and secondary amines the transformation of reactants to products necessarily involves the transfer of a proton at some stage of the reaction. Such reactions are potential-... 

The fourth chapter gives a comprehensive review about catalyzed hydroamina-tions of carbon carbon multiple bond systems from the beginning of this century to the state-of-the-art today. As was mentioned above, the direct - and whenever possible stereoselective - addition of amines to unsaturated hydrocarbons is one of the shortest routes to produce (chiral) amines. Provided that a catalyst of sufficient activity and stabihty can be found, this heterofunctionalization reaction could compete with classical substitution chemistry and is of high industrial interest. As the authors J. J. Bmnet and D. Neibecker show in their contribution, almost any transition metal salt has been subjected to this reaction and numerous reaction conditions were tested. However, although considerable progress has been made and enantios-electivites of 95% could be reached, all catalytic systems known to date suffer from low activity (TOP < 500 h ) or/and low stability. The most effective systems are represented by some iridium phosphine or cyclopentadienyl samarium complexes. 

A rather complex fused isoindoline (87) has been found to show good anorectic activity. This substance differs from other anorectic agents by not being a p-phenethylamine analogue. Preparation of this compound starts by reaction of a substituted benzoyl-benzoic acid (82) with ethylene diamine. The product (84) can be rationalized as being the aminal from the initially obtained monoamide 83. This is then subjected to reduction with lithium aluminum hydride... 

Another situation is observed when salts or transition metal complexes are added to an alcohol (primary or secondary) or alkylamine subjected to oxidation in this case, a prolonged retardation of the initiated oxidation occurs, owing to repeated chain termination. This was discovered for the first time in the study of cyclohexanol oxidation in the presence of copper salt [49]. Copper and manganese ions also exert an inhibiting effect on the initiated oxidation of 1,2-cyclohexadiene [12], aliphatic amines [19], and 1,2-disubstituted ethenes [13]. This is accounted for, first, by the dual redox nature of the peroxyl radicals H02, >C(0H)02 and >C(NHR)02 , and, second, for the ability of ions and complexes of transition metals to accept and release an electron when they are in an higher- and lower-valence state. 

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