Structure of aminoguanidine hemioxalate. Implications for the synthesis of amidinohydrazones

Platinum(II) and Palladium(II) Complexes with N‐Aminoguanidine

“…Distances and angles at the platinum centre have usual values, while distances and angles of the Amgu moiety are comparable to those observed for uncomplexed Amgu cations in the solid state. [16,[26][27][28] Distances C1-N1, C1-N2 and C1-N3 have approximately equal values, as should be expected for a delocalized guanidinium system. The Amgu ligand is approximately planar (maximum deviation from the least-squaresplane defined by the atoms C1, N1, N2, N3, and N4 is 0.039(2) Å for N3), confirming that nitrogen N3 is sp 2 hybridized.…”

“…Distances C1-N1, C1-N2 and C1-N3 are again of approximately equal values, and are comparable with those for protonated uncomplexed ligand. [16,[26][27][28] There is no localised double bond, and the positions of the H atoms and the planarity of the ligand suggest an sp 2 hybridisation for all atoms except N4, which remains sp 3 -hybridised. The packing of the Pt units gives rise to infinite stacks of square-planar complexes (correlated by a c glide plane) with a Pt-Pt separation of 3.332(1) Å.…”

The chemistry of aminoguanidine derivatives – preparation, crystal structure, thermal properties, and molecular docking studies of aminoguanidinium salts of several carboxylic acids

“…4) and nearly perpendicular to the oxamate group, making a dihedral angle of 81.53°. The bonds C1-N1 and C1-N2 were 1.3221 (17) [3,9,11,12]. The structure can be regarded as an aminoguanidinium derivative, where the positive charge was delocalized over the guanidinium moiety and the negative charge over the -CO-COO group.…”

“…Only a few salts, such as aminoguanidinium hemioxalate [9], hydrogen-L-tartrate monohydrate [3] and squarate [10], have been reported in the literature. Previously, we reported the structures of aminoguanidinium hydrogen succinate [11] and aminoguanidinium hydrogen fumarate [12].…”

Unexpected ring closure reaction of α,β‐unsaturated ketones with aminoguanidine. entry into 1,3,5‐trisubstituted pyrazoles

“…The reaction mode of the key step under acid catalysis is controlled by protonation, which occurs at the imine nitrogen as evidenced by the X-ray structure of the aminoguanidine salt [16]. Due to the extensive delocalization of the positive charge over the guanidyl group in the monocation form [16,17], an intervention via the former nitrogen atom of the aminoguanidine will hence be favored.…”