Cobalt iodide hydrate

CYCLOPROPANATION Bis[(-)-camphor-quinone-a-dioximato] cobalt(II) hydrate. Diethylzinc-Methylene iodide. Rhodium(II) caiboxylates. 

The higher iodides, however, tend to be unstable and decomposition occurs to the lower iodide (PI5 -> PI3). Anhydrous chlorides and bromides of some metals may also be prepared by the action of acetyl (ethanoyl) halide on the hydrated ethanoate (acetate) in benzene, for example cobalt(II) and nickel(II) chlorides ... 

Decomposition of most cobalt(III) complexes by boiling with alkali gives a brown precipitate of the hydrated oxide C02O3. aq (p.402). This will quantitatively oxidise iodide to iodine. 

Meanwhile, Wacker Chemie developed the palladium-copper-catalyzed oxidative hydration of ethylene to acetaldehyde. In 1965 BASF described a high-pressure process for the carbonylation of methanol to acetic acid using an iodide-promoted cobalt catalyst (/, 2), and then in 1968, Paulik and Roth of Monsanto Company announced the discovery of a low-pressure carbonylation of methanol using an iodide-promoted rhodium or iridium catalyst (J). In 1970 Monsanto started up a large plant based on the rhodium catalyst. 

Photolysis of ion pairs of cobalt(III) complexes with iodide ions leads to oxidation of iodide and reduction of the complex.55,63-86 Under the normal experimental conditions, however, most of the light is absorbed by free iodide and the reduction of the complex is effected by hydrated electrons produced as in reaction (36).86... 

Both dextro- and levo-tris (ethylenediamine) cobalt (III) iodide monohydrate crystallize in deep orange needles or rhombs. The racemic phase which separates as the 1-hydrate is much less soluble in water. Racemization ensues... 

Rate constants for zinc as the hydrated ion and in complexes with bromide and iodide ions are given in Fig. (4). Those for zinc in m. KCl and KCNS are 6 x lo and 17 x iO . Thus k increases in the order (NO a) < A(C1") < ft(Br-) < ft(CNS ) < k I ). Preliminary results for nickel and cobalt indicate a similar order for A Br ), A(CNS ) and k I ) these reactions are a great deal slower than for zinc. It appears possible that increasing covalency of bonding between the metal ion and its addenda, lowers the activation energy for discharge. 

Methylbromoarsines, synthesis 26 Vanadium(III) fluoride, synthesis 27 Sulfur(IV) fluoride, synthesis 33 Peroxydisulfuryl difluoride, synthesis 34 Trichloro(tripyridine)chromium(III), synthesis 36 Tris(3-bromoacetylacetonato)chromium(III), synthesis 37 Trichloro(tripyridine)molybdenum(III), synthesis 39 Uranyl chloride 1-hydrate, synthesis 41 Rhenium(III) iodide, synthesis 50 Potassium hexachlororhenate(IV) and potassium hexa-bromorhenate(IV), synthesis 51 Iron-labeled cyclopentadienyl iron complexes, synthesis 54 Inner complexes of cobalt(III) with diethylenetriamine, synthesis 56... 

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