Ammonium acid formate cobalt chlorides

Ammonium Tetranitrito - diammino - cobaltate, [Co(XH3)2 (N02)4]NH4, is prepared from cobaltous chloride by mixing an aqueous solution of the salt with aqueous ammonium-chloride solution, sodium nitrite, and ammonia, and oxidising the mixture by passing air through it for several hours. The solution is allowed to stand in air for some days, when crystals gradually separate. These are collected, washed, and reerystallised from water.3 The substance crystallises in brown rhombic prisms. It is decomposed on treatment with potassium hydroxide with evolution of ammonia, and a cold solution reacts with ammonia in presence of ammonium salts, with formation of flavo-dinitro double salts, of which [Co(NH3)4(N02)2][Co(NH3)2(N02)4] is typical. Oxalic acid transforms it into the oxalato-dinitrito-diammino-salt, [Co(NH3)2(N02)2(C204)]NH4. 

For this purpose the effect of the concentration of potassium chloride added to a borate buffer solution (total concentration of boric acid and potassium borate 0,10 mole/liter, pH 8,4) on polaro-gp ams for the Co (II) - cysteine system, with constant cobalt chloride (1,74 mmole/liter) and cysteine (0,08 mmole/liter) concentrations, was investigated. The borate buffer solution was used in place of the traditional ammoniacal buffer solution in order to avoid a number of complications and, primarily, decrease in the buffer capacity of the ammoniacal solution near the electrode when potassium chloride is added, since ammonium ions (being proton donors) also participate in the formation of the outer layer of the electric double layer. The pH value of the solution was selected so that the solution would contain approximately equal amounts of anions and cysteine zwitterions (pl am 8.33). 

Another catalytic system which has been successfully applied to the autoxidation of substituted toluenes involves the combination of Co/Br" with a quaternary ammonium salt as a phase transfer catalyst (ref. 20). For example, cobalt(II) chloride in combination with certain tetraalkylammonium bromides or tetraalkylphosphonium bromides afforded benzoic acid in 92 % yield from toluene at 135-160 °C and 15 bar (Fig. 19). It should be noted that this system does not require the use of acetic acid as solvent. The function of the phase transfer catalyst is presumably to solubilize the cobalt in the ArCH3 solvent via the formation of Q + [CoBr]. ... 

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