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Acid interaction with nickel

When formed on cellulose [thin-layer-chromatography (TLC) plates], the colored forms of 6-nitro-8-methoxyBIPS and of trimethylindolinospironaphthoxa-zine are stabilized against thermal or photoerasure by interaction with nickel or zinc salts of hydroxy carboxylic acids or dicarboxylic acids. The zinc salts of 1-hydroxy-... [Pg.50]

We expected to control the direction of OTM reaction over NiO by sur ce modification, namely making use of the interaction between NiO and other conq>onents to beget a synergistic effect. In this paper, two completely different behaviors of the oxidative transformation of methane were performed over the nickel-based catalysts because of the different modifications by alkali metal oxide and rare earth metal oxide and the different interactions between nickel and supports. Furthermore, the two completely different reactions were related with the acid-base properties of catalysts and the states of nickel present. [Pg.454]

Reaction of 3 with 1 equivalent of a phosphine results in formation of "phosphine-modified catalysts (4). The complex formed from 7r-allyl-nickel chloride, tricyclohexylphosphine, and methylaluminum dichloride (4a) has been isolated and its structure determined crystallographically (see Fig. 1) (57) The phosphine is bonded to the nickel atom, and interaction with the Lewis acid takes place via a chlorine bridge. The bridging chlorine atom is almost symmetrically bound to both the nickel... [Pg.111]

The controlling factor of the reductive elimination on Pd(R)(C=CR )Lm (Eq. 5) may be different from that observed with the nickel complex. However, participation of a similar activation process by coordination of electron-with-drawing RX and R C=CH is conceivable. The Pd(R)(C=CR )Lm-type complex can be isolated, and it has been shown that isolated Pd(R)(C=CR )Lm undergoes the reductive elimination exhibited in Eq. 5 [8]. The reductive elimination seems to be enhanced by addition of Cul. Cul may interact with the Pd complex, and an acceleration effect of Lewis acids on the reductive elimination reaction of NiR2(bpy) has been shown [22]. The X-ray crystallographic structure of an isolated Pd(R)(C=CR )Lm (R=C6H4Me-p R =C6H5) has been determined [8]. [Pg.183]

Carboxylic acids (acetic, halo substituted acetic and benzoic adds, HA) have been shown75 to interact with V-phenylbenzohydroxamates of copper(II), nickel(II) and cobalt(II) with the formation of adducts with the formula M(LL)2(HA)2 (where LL is the anion of hydroxamic acid). [Pg.507]

Nickel 10 mg Interaction with iron absorption, nucleic acid, lipid metabolism Unknown Unknownb... [Pg.762]

Syntheses of 5,12-dioxocyclams containing the quinoxaline nucleus have utilized the ring opening of both rings of 3,3,6-trimethyl-l-azapenam 148. Treatment of 148 with acid gave the cyclam (Equation 16) after reduction of the imine. Unfortunately, this and related cyclams and their nickel complexes showed little useful biological activity in their interaction with DNA <2003JOC4179>. [Pg.260]

The hypothesis of formation of oxygenated compounds as intermediate products was rejected by Eidus on the basis of experiments on the conversion over cobalt of methyl and ethyl alcohols and formic acid which were found to form carbon monoxide and hydrogen in an intermediate step of the hydrocarbon synthesis (76). Methylene radicals are thought to be formed on nickel and cobalt catalysts (76) by hydrogenation of the unstable group CHOH formed by interaction of adsorbed carbon monoxide and hydrogen, while on iron catalysts methylene radicals are probably formed by hydrogenation of the carbide (78,81). Carbon dioxide was found to interact with the alkaline promoters on the surface of iron catalysts as little as 1 % potassium carbonate was found to occupy 30 to 40% of the active surface area. The alkali also promotes carbide formation and the synthesis reaction on iron (78). [Pg.277]

In the diet and at the tissue level, ascorbic acid can interact with mineral nutrients. In the intestine, ascorbic acid enhances the absorption of dietary iron and selenium reduces the absorption of copper, nickel, and manganese but apparently has little effect on zinc or cobalt. Ascorbic acid fails to affect the intestinal absorption of two toxic minerals studied, cadmium and mercury. At the tissue level, iron overload enhances the oxidative catabolism of ascorbic acid. Thus, the level of dietary vitamin C can have important nutritional consequences through a wide range of inhibitory and enhancing interactions with mineral nutrients. [Pg.551]


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With nickel

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