Carbonatopentamminecobalt III nitrate

Five grama of carbonatopentamminecobalt (III) nitrate (No. 118) are added in small portions to a mixture of 15ml of water and 12g of glacial acetic acid. The reaction mixture is concentrated on a steam bath for iy -2 hours during this time the red crystalline product separates. After cooling to room temperature, 40ml of water are added and the solid is filtered off. The mother liquor is removed from the filter flask and reserved, then the salt is washed with 50ml of ice-cold water, followed by 95% alcohol and ether. 

Ten grams of carbonatopentamminecobalt (III) nitrate ti-hydrate (See No. 118) are suspended in 10ml of water and 20ml of 1 1 nitric acid and water are added slowly in small portions. When the effervescence has stopped, after about 10 minutes, 100ml of alcohol (methyl or ethyl) are mixed with the liquid. The red precipitate is filtered off,... 

Many methods have been used for the preparation of various acidopentammineeobalt(III) salts.1 In some instances these procedures are specific for the synthesis of a particular salt. The procedure suggested here involves the reaction of carbonatopentamminecobalt(III) nitrate with an acid or acid salt. The resulting reaction mixture may then be digested for a short time to yield the desired product, or the aquo complex is isolated and converted to the acido compound at an elevated temperature. This method appears to be completely general and has been used to synthesize complexes containing coordinated bromide, chloride, thiocyanate, sulfate, formate, and various substituted acetates, benzoates, and benzenesulfonates in addition to those described here. 

Ten grams of carbonatopentamminecobalt(III) nitrate (0.036 mol) is suspended in 25 ml. of water, and 4.5 g. of ammonium hydrogen fluoride (0.079 mol) and 15 g. of ammonium fluoride (0.405 mol) are added. The reaction mixture is kept at approximately 90° in a water bath for 1 hour, with occasional stirring. During this digestion some decomposition takes place, and noticeable quantities of ammonia are evolved. The mixture is then cooled to room temperature, 75 ml. of water being added to keep the products in solution. This solution is filtered, and 20 g. of solid ammonium nitrate (0.25 mol) is added to the filtrate. Pink crystals separate immediately after the mixture is cooled in an ice-salt bath. The product is collected on a filter, washed with 10 ml. of ice-cold water, followed by alcohol and ether, and then dried at 90°. Yield, 6 g. (58%). 

Ten grams of carbonatopentamminecobalt(III) nitrate (0.036 mol) is suspended in 25 ml. of water, and 20 ml. of colorless nitric acid (1 1 concentrated acid and water) is added with stirring. When the evolution of carbon dioxide has stopped (10 minutes), 100 ml. of methanol is added, the aquopentammine cobalt (III) nitrate is collected on a filter, and washed with alcohol and ether. This salt is heated at 100° for 18 hours (until 1 mol of water is lost), yielding 10 g. (83 %) of the desired material. Anal. Calcd. for [Co(NH3) 6-N03](N03)2 NHs, 25.8. Found NH3, 25.6. 

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