Synthesis and Structures of Hydroxylamine Derivatives: Potassium N-Hydroxycarbamate and Hydroxylammonium N-Hydroxycarbamate Hydroxylaminosolvate

Two new N-hydroxycarbamate derivatives have been synthesized and structurally characterized (single-crystal XRD, 100 K) for the first time: hydroxylammonium N-hydroxycarbamate hydroxylaminosolvate NH3OH+[HO–N(H)–C(O)–O]–·NH3O (I) and potassium N-hydroxycarbamate coordination polymer [HO–N(H)–C(O)–O]–K+ (II). The compounds are synthesized under mild conditions due to atmospheric CO2 fixation by a solution of free hydroxylamine in tert-butyl alcohol. The anion, NH3OH+ cation, and NH3O zwitterion in the structure of compound I form a dense three-dimensional network of hydrogen bonds including an exclusively short O···O contact (2.4477(18) Å). Compound II is a three-dimensional coordination polymer in which the potassium ion has a coordination number of 8 and coordinates not only oxygen atoms but also the amide nitrogen atom (K–N = 2.838(3) Å). The data obtained substantially extend the undeveloped crystal chemistry of the class of N-hydroxycarbamates.