Cobalt hydrogen -tartrate

An experiment you may have carried out in previous years Involves the reaction of a solution of potassium sodium tartrate (Rochelle salt) with hydrogen peroxide, which Is catalysed by cobalt(ll) chloride solution. 

The reaction is not disturbed by silver or copper, or by iron(III), chromium or aluminium in the presence of ammoniacal tartrate solution if zinc is present, ammonium chloride should first be added cobalt(III) ions represss the sensitivity and should be oxidized to the tervalent state with hydrogen peroxide iron(II) interferes and should be oxidized and alkaline tartrate solution added before applying the test. 

RESOLUTION (S)-l-Amino-2-(silyloxyme-thyl)pyrrolidines. 1,1 -Binaphthyl-2,2 -diyl hydrogen phosphate. r-Butyl hydroperox-ide-Diisopropyl tartrate-Titanium(IV) iso-propoxide. Di- x-carbonylhexacarbonyldi-cobalt. (2S)-(2a,3aa,4a,7a,7aa)-2,3,3a,4,5,6,7,7a-Octahydro-7,8,8-trime-thy 1-4,7-methanobenzofurane-2-ol. 

Kinetic resolutions. A chiral alcohol is obtained on. selective removal of one enantiomer by acetylation using a chiral analog 1 of DMAP, or by oxidation based on hydrogen transfer to acetone mediated by a Ru complex 2. Benzylic secondary alcohols are resolved by selective pivaloylation with optically activeA-pivaloyl-4-t-butylthiazolidine-2-thione. A kinetic resolution of sulfoxides is based on asymmetric oxidation with (i-PrO)4Ti-cumyl hydroperoxide in the presence of a tartrate ester. Kinetic resolution of 1,3-diarylallenes is realized by selective oxidation with NaClO catalyzed by a chiral (salen)manganese(III) complex, whereas asymmetric hydrolysis of terminal epoxides with the aid of a chiral (salen)cobalt(II) catalyst solves the problem of their accessibility. 

Reduction of bis(pentane-2,4-dionato)ethylenediaminecobalt(iii) by chromium(ii) occurs by an inner-sphere path involving both singly bridged and doubly bridged transition states, in addition to the expected outer-sphere path. From the crystal structure of (-I- )5g9-oxalatobis(ethylenediamine)cobalt(iii) hydrogen-d-tartrate monohydrate it was found that the optically active complex is locked by the (H-d-tartrate) units of the right-handed spiral chain structure along the b-axis. ... 

From the absorption spectra of the various green solutions produced by the reaction of hydrogen peroxide on a cobaltous salt in the presence of potassium (or sodium) bicarbonate, acetate, tartrate, citrate or oxalate, Durrant - concluded that the green color depended on complex ions with the >Co O Co < nucleus, and that the differences in tint of green and in absorption spectra depended probably on the various association of carbonyl groups attached to the nucleus. On account of his detailed study, the reaction discovered by Field has been called Field-Durrant reaction ... 

Yamane et al.[13] determined cobalt in sea water and river waters with a catalytic spectrophotomeiric method after on-line preconcentration using a column packed with quinolin-8-ol immobilized on silica gel. The tartrate eluate from the preconcentraiion had to pass through a second column packed with a strongly acidic cation exchanger to remove iron(III) and manganese(II) which interfere in the catalytic reaction of oxidation of protocatechuic acid by hydrogen peroxide. An extremely low detection limit of 0.005 /ig 1 was obtained. However, the sampling frequency was less than 2 h . ... 

Beside the tartrate, other organic salts—notably the oxalate and the formate—yield the more easily produced pyrophoric metals, i.e. lead, nickel, and cobalt, if the pyrogenic decomposition is performed at low temperature. These organic salts or the oxides of nickel, cobalt, and iron, under hydrogen at about 300X, also furnish the self-flammable metals, but in the case of iron, a pyrophoric ferrous oxide (FeO) may first appear by reduction with hydrogen as well as by reduction under carbon monoxide. 

Cl ijHagCoNgOi 5, Hydrogen tris(ethylenediamine)cobalt (III) d-tartrate trihydrate, 43B, 1146... 

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