Dinitrobis ethylenediamine cobalt III Nitrite and Nitrate

Several preparations of salts of the czs-dinitrobis(ethyl-enediamine)cobalt(III) ion have been reported in the literature. The most usual is that of Werner/ modified by Holtzclaw, Sheetz, and McCarty, beginning with potassium hexanitrocobaltate(III). However, this method makes use of a starting material which is difficult to prepare in high purity and to dry thoroughly, involves critical temperature control, and produces a yield of about 15%. The following procedure, which utilizes rons-dichlorobis(ethylenedi-amine)cobalt(III) chloride as the starting material, provides a 60% yield of cfs-dinitrobis(ethylenediamine)cobalt-(III) nitrite. The nitrite is then easily converted to the nitrate. 

Thirty grams (0.105 mol) of rans-dichlorobis(ethylene-diamine)cobalt(III) chloride is dissolved in 150 ml. of cold 

The cfs-dinitrobis(ethylenediamine)cobalt(III) nitrate may be analyzed electrolytically or volumetrically for cobalt. Calcd.for[Co(en)2(N02)2]N03 Co, 17.69. Found Co, 17.6. By checkers Co, 17.76, 17.80. The qualitative test for the cis isomer described by Holtzclaw, Sheetz, and McCarty and infrared analysis confirmed that the product is the correct isomer. As a final check, the compound was resolved according to the method of Dwyer the specific 

Inorganic Syntheses, Volume VIII Edited by Henry F. Holtzclaw, Jr. Copyright 1966 by McGraw-Hill Book Company, Inc. 

cis-BROMOAMMINEBIS(ETHYLENEDIAMINE)-COBALT(in) BROMIDE, cis- AND trans-AQUOAMMINEBIS(ETHYLENEDIAMINE)-COBALT(m) BROMIDE, AND cis- AND trans-AQUO AMMINEBIS (ETH YLENEDIAMINE)-COBALT(in) NITRATE 

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Diiron enneacarbonyl, synthesis 46 Triiron dodecacarbonyl, synthesis 46 Tricarbonyl(cyclooctatetraene)iron, synthesis 47 Iron carbonyl complexes of triphenylphosphine, triphenyl-arsine, and triphenylstibine, synthesis 48 cis-Dinitrobis(ethylenediamine)cobalt(III) nitrite and nitrate, synthesis 60... 

The CT s-dinitrobis (ethylenediamine) cobalt(III) nitrite is dissolved in a minimum volume of lukewarm water (no warmer than 60°). Concentrated nitric acid is added dropwise until gas evolution ceases. During the addition of the acid, as-dinitrobis (ethylenediamine) cobalt (III) nitrate precipitates. The mixture is cooled in an ice-salt bath, and the brown-yellow crystals are removed by filtra-tration. The salt is recrystallized twice from water, care being taken to keep the temperature of the solution below 60°. The yield of as-dinitrobis(ethylenediamine)-cobalt(III) nitrate is 2.0 g. (15% based on ethylenediamine). Anal. Calcd. for [Coen2(N02)2]N03 Co, 17.7. Found Co, 17.8. 

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