A hydrogenbridged adduct 3,4,6,7,8,9-hexahydro-2H-pyrimido[1,2-a]pyrimidin- 1-ium [1,3-bis(tertbutyldimethylsilyloxy)-1,3-bis(pyridin-2-yl)propan-2-ylidene] nitronate acetonitrile monosolvate

Abstract

The title compound, C 7H 14N 3+·C 25H 40N 3O 4Si 2-·CH 3CN, was obtained by the reaction of 2-nitro-1,3-di(pyridin-2-yl)-1,3-di(tertbutyldimethylsilyloxy) propane with 1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidine. Two hydrogen bonds stabilize the Lewis acid/base pair of the nitronate and the guanidinium moiety with N⋯O distances of 2.772 (3) and 2.732 (3) Å. Both hydrogen atoms are more closely bound to the guanidinium [N - H distances of 0.83 (3) and 0.93 (3) Å] than to the nitronate moiety. The nitronate is doublebonded to the respective carbon with an N=C bond length of 1.316 (3) Å.