Cobalt trans-, chloride

Lithium tetranitrodiamminecobaltate(III) Trans-dichlorobis(ethylenediamine)cobalt(III) chloride... 

Carbonatobis (ethylenediamine)cobalt(III) bromide Tris(cthylenediamine)cobalt(III) chloride Trans-dinitrotetramminecobalt (III) chloride Tris (propylenediamine) cobalt (III) chloride Cis-dinitrotetramminecobalt(III) chloride... 

The unsymmetrical nature of / -mercaptoethylamine should lead to geometric isomerism among its metal complexes, cis and trans isomers might be expected with the square planar nickel (II) and palladium (II) derivatives and facial and peripheral isomers with cobalt (III). However, during the course of the preparation of various samples in which the procedure and experimental conditions were varied, no evidence of such isomerism was apparent (6, 15). This is particularly evident in the case of the cobalt (III) complex, CoL3. Samples prepared by the addition of cobalt (II) chloride 6-hydrate to strongly basic aqueous solution of the ligand and by displacement of ammonia and (ethylenedinitrilo)-... 

Fifty grams of acid-free trcns-diehlorodiethylenediamine-cobalt (III) chloride (No. 131) are dissolved in the minimum of water at 90°C. If the hot green solution is allowed to stand for a short time it begins to turn purple because of hydrolysis to the trans-chloroaquo chloride. To the hot liquid are added 18.5 of anhydrous sodium carbonate and the mixture is stirred until solution is complete. The red liquid is then thoroughly cooled in ice, filtered, and thoroughly drained. 

The traditional method of isolating the trans-dichlorobis-(ethylenediamine)cobalt(III) chloride salt by evaporation of the reaction mixture to dryness in the steam bath gives some reduction to cobalt(II). To avoid this, the chloride salt in the following procedure is isolated by saturation of the reaction mixture with hydrogen chloride gas and by precipitation with standing at room temperature. As an alternative method, the reaction mixture from the preparation of (carbonato)bis(ethylene-diamine)cobalt(III) chloride can be used as the starting material. 

Dichlorobis (ethy lenediamine) cobalt-(III) chloride, cis- and trans-, 2 222, 223... 

Metal—Carbon Bonds in Cobalt-Catalyzed Polymerization. Concentrations of metal-carbon bonds were determined (using tritium labelled alcohol) with increase in conversions. Experiments were made in two solvents (petrol and benzene) with two cobalt salts (chloride and naphthenate) under conditions giving rise either to liquid mixed structure or to high trans polybutadiene. The data are summarized in Table XI. Table XII and Figure 11 shows optical properties of some cobalt salts and complexes. 

The preparation of bis(bipyridyl) (702) and bis(phenanthroline) cobalt(III) complexes (576) has been the subject of a number of papers. Interest centers on the possibility of cis-trans isomerism in these complexes, since it would seem that the close approach of the 6,6 -(bipyridyl) and 2,9-(phenanthroline) protons in the trans complex would make this stereochemistry unattractive for central ions such as co-balt(III), rhodium(III), or iridium(III). Cis complexes are well established, but a violet compound claimed to be anionic cobalt(II) species (21, 573, 591). 

The tetraamminedinitrocobalt(lll) salts represent the second longest known case of geometric isomerism among coordination compounds. The reddish-yellow trans compounds were first prepared in 1875 by air oxidation of a solution of cobalt(II) chloride containing ammonia, sodium nitrite, and ammonium chloride by Wolcott Gibbs, who called them croceo salts. The brownish-yellow cis compounds were first prepared in 1894 by reaction of tetraamminecarbonato-cobalt(III) salts with sodium nitrite by Jorgensen, who called them flavo salts. The two series correspond completely to the bis(ethylenediamine)dinitrocobalt-(111) salts. 

A large majority of diacidobis(l, 2-ethanediamine)cobalt(III) complexes can be synthesized from the (carbonato)bis(l, 2-ethanediamine)cobalt(III) ion. This is now readily available in high yield and purity.1 cis- and trans-Dichlorobis(l, 2-ethanediamine)cobalt(III) chlorides are obtained from the carbonato complex with hydrochloric acid using appropriate conditions. These isomeric dichloro salts are widely used starting materials for further syntheses. In this respect, the analogous dibromo complexes can be more convenient starting materials because bromide is substituted from the cobalt center more readily than is chloride ion. The milder conditions minimize the production of cobalt(II), a common side reaction. 

The title complex (as the chloride) was first reported by Kyuno and Bailar,1 who obtained cis-a and m-(i isomers by the ligand displacement reaction of cis-a-dichloro(N,N -bis(2-aminoethyl)-l,2-ethanediamine)cobalt(lll) chloride in gaseous and liquid ammonia. However, its trans isomers were not prepared until 1980.2... 

Co(en)2(N02)2]N03 cis- and trans-Dinitrobis(ethylenediamine)co-balt(III) nitrate, 4 176, 177 [Co(en)3]Cl3 Tris(ethylenediamine)-cobalt(III) chloride, 2 221 CoF3 Cobalt(III) fluoride, 3 175 [Co NH(C5H4N)21C12] Dichloro-(di-2-pyridylamine)cobalt (II), 6 184... 

Left ds-tetraamminedichloro-cobalt(lllj chloride. Right trans-tetraamminedichlorocobaltflllj chloride. 

CljCoN C His, Cobalt(III), dichloro-bis(l,2,-ethanediamine)-, trans-, chloride, 29 167... 

Left cis-tetraamminedichloro-cobalt(III) chloride (left). Right trans-tetraamminedichloro-cobalt(III) chloride (right). 

Another possibility is anionic polymerization with alkyllithium in combination with barium compounds such as barium 2,4-pentanedionate [192-194, 203-205]. Also, cobalt(II) chloride in combination with diethylaluminum chloride and triethylamine is used, yielding a polymer with 91% trans-l A and 9% 1,2 structures. 

C7H28CI3C0N10S3, trans-Dichlorobis(ethylenediamine)cobalt III) chloride - tris(thiourea), 39B, 440 C8H6K3M0N6O3S6 r Potassium hexaisothiocyanatomolybdate(lII) hydrate-acetic acid, 33B, 422... 

Cl2Ni,Pd, Bis(ethylenediamine)palladium(II) chloride, 31B, 375 C Hi gClaCoNi, trans-Dichlorobis(ethylenediamine)cobalt (III) chloride, 23, 572... 

C6H24NeNi06, Trisethylenediaminenickel nitrate, 24, 605 C6H25ClaCoN202, trans-Dichlorobis(l-propylenediamine)cobalt(III) chloride hydrochloride dihydrate, 27, 833 CgH26AU2N6O12S4, Ethylenediammonium bis-cis-(ethylenediamine-disulf itoauratedll)), 41B, 941... 

Cl5H4 4CI3C0N6O4, (-)589 Tris-( + )-trans-l,2-diaminocyclopentane)cobalt (III) chloride tetrahydrate, 37B, 544 CleF2aHgN2S8, Bis[2,3,4,5-tetrakis(trifluoromethylthio)pyrrolyl]mer-cury, 45B, 1173... 

Cl 8Hi,8N90i 2Rh, ( + )-Tris-( (-)-trans-l, 2-diaminocyclohexane)rhodium-(III) nitrate trihydrate, 40B, 903 Cl8H52CI3C0N6O5, (-)589"Tris(+trans-1,2-diaminocyclohexane)cobalt-(III) chloride pentahydrate, 35B, 713 Cl8H52CI3C0N6O5, Bis((S,S)-trans-1,2-diaminocyclohexane)-(R,R)-trans-1,2-diaminocyclohexanecobaltdII) chloride pentahydrate, 43B, 1151... 

CbH2 2C1CoNi,05, trans-Bis(ethylenediaminomonoacetato)cobalt (III) chloride dihydrate, 40B, 964... 

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