Dinitrosyl Iodide

The iodine solution is added dropwise at such a rate that the entire quantity of iodine is added over a period of 45-74 minutes. If the iodine is added too rapidly, iodination of acetone will take place. Caution. Iodoacetone species are extremely powerful lacrimators. During the addition of the iodine solution, a very slow flow of nitrogen should be maintained (1-5 bubbles per minute). The resultant product should consist of a dark brown solution and unreacted iron (150-mole % excess). This excess iron powder is necessary for the over-all reaction, for reducing the iodination of acetone, and for improving the yield of product. 

The remaining traces of acetone and other volatile products are removed by vacuum distillation into the liquid-nitrogen trap by 

The sublimation gives dense, black, lustrous crystals with metallic reflecting surfaces. The yield is 59.8 g. (or 82%) based on iodine. The product was identified by its mass spectrum,2 infrared spectrum, and elemental analysis. Anal. Calcd. for [Fe(NO)2I]2 Fe, 23.0 I, 52.3 mol. wt. (monoisotopic), 486. Found Fe, 23.4 I, 51.8 mol. wt., 486. Infrared spectrum, observed i NO, 1810 and 1770 cm.-1 in literature , 1818 and 1771 cm.-1. 

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The cobalt analog of the iron dinitrosyl iodide is prepared according to the above procedure with only minor modifications, which are outlined below. Anhydrous deoxygenated reagent-grade acetone and 35.4 g. of cobalt powderf are added to the 1000-ml. flask and allowed to react with the ether solution of iodine (38.1 g. (0.15 mole) of iodine in 300 ml. of ether) over a period of 30 minutes. Then nitric oxide is admitted to the flask. The reaction... 

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