Tetraethylammonium Cyanate and Cyanide

A recently developed general method of synthesis for the tetraalkylammonium cyanides was extended subsequently to the cyanates. Previous to 

Inorganic Syntheses, Volume XVI Edited by Fred Basolo Copyright 1976 by McGraw-Hill, Inc. 

A 6- by 50-cm column terminating in a Teflon stopcock is packed with 1 lb of IRA-400 resin and charged with 454 g (5.5 moles) of potassium cyanate dissolved in 41. of 50% aqueous methanol. The flow rate during the charging procedure should not exceed 2 drops/sec. After completion of this step, the column is rendered anhydrous by rinsing it with 51. of absolute methanol. An increased flow rate can be used for this step. 

A solution of 43.3 g (0.21 mole) of tetraethylammonium bromide in 350 ml of anhydrous methanol is placed on the prepared anhydrous column and eluted to a volume of 21. with absolute methanol. Again a flow rate of 2 drops/ sec is advised. The eluate is concentrated on a rotary evaporator (water aspirator) to a very viscous solution, which is then evaporated to dryness under dynamic vacuum (10- torr) at ambient temperature. The yield, based upon tetraethylammonium bromide, is 27 g (75 %). Further purification was not found necessary, but if additional purification of the products is desired, it can be accomplished by dissolving the product in 150 ml of acetonitrile in a dry-box. The pure cyanate is precipitated by the addition of 200 ml of ethyl acetate. The product is isolated by filtration in a dry-box and dried under dynamic vacuum at ambient temperature. Anal. Calcd. for C9H2oN20 C, 62.79 H, 11.63 N, 16.09 O, 9.40. Found C, 62.7 H, 11.8 N, 16.3 O, 9.3. 

Tetraethylammonium cyanate is a white solid which deliquesces in air but can be stored for an indefinite time in a dry inert atmosphere. It is soluble in 

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