CRYSTAL AND MOLECULAR STRUCTURE OF A TRANS-NITROSO DIMER (ONCH2CH2NO2)2

The reaction product of ethylene and N2O3, is identified by a three-dimensional, single-crystal X-ray diffraction study as the trans dimer of 2-nitronitrosoethane, with dimerization through the nitroso nitrogens at a center of symmetry. The space group is P21/n, with two molecules in a unit cell of dimensions a = 8.749, b = 9.786, c = 4.945 Å, and β = 95.6˚. The structure was solved by reiterative application of the Sayre equation. The nitroso N-O bond length of 1.262 ± 0.004 Å is considerably shorter than earlier estimates of this distance in C-nitroso dimers. The N-N bond length is 1.304 ± 0.006 Å. The final agreement factor R1 is 10.8% for 610 observed reflections. © 1969, American Chemical Society. All rights reserved.