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Use of salts and co-crystals of active pharmaceutical ingredients (APIs) as a method for tuning their delivery and activity is an area of growing interest. Modifying API properties such as solubility by finding new salts that employ similar hydrogen-bonding have been successful. In an effort to further study the hydrogen-bonding patterns of the maleate ion with other diisopropylammonium we report here the synthesis and diisopropylammonium maleate. The salt was isolated from reaction between diisopropylamine and maleic acid in methanol. The results of elementary analyzes (CHN) showed the presence of the nitrogen atom of diisopropylamine, carbon atoms and hydrogen. The IR spectrum of diisopropylammonium hydrogen maleate, showed the presence of two intense bands due to the vibrations of symmetricand anti-symmetric valence of the carboxylate group and a wide absorption due to the NH2 groups of the cation. Those which has been confirmed by crystallography. The asymmetric unit contains one diisopropylammonium cation, iPr2NH2+ and one hydrogen maleate anion. In the structure, anions which present an inner O-H…O hydrogen bond are linked to cations through N-H…O hydrogen bonds leading to infinite chains. Chains are connected to their neighbours through weak C-H…O hydrogen bonds affording a layer. The study of the interactions of diisopropylammonium hydrogen menaleate, by the presence of hydrogen bonds leading to supramolecular architectures has shown the possibility of its use in Active Pharmaceutical Ingredients (API).

Five new compounds are isolated from reactions carried out in solution. All the compounds are characterized by, Infrared and Mossbauer spectroscopies. Spectroscopic studies have shown the presence of different carracterristic bands, notably υ (PO) vibrations coming from triphenylphosphine oxide, with wide absorption due to the NH2 groups coming from urea and the intense doublet which show the presence of phenyl groups. The proposed structures, in the solid state, are discrete though hydrogen bonding interactions may occur. Event in this study is the dearylation evidenced, cleaved Sn-Ph bonds occurring in the presence of triphenylphosphine oxide or urea, during some reaction processes. In the presence of triphenylphosphine oxide, the dearylation is followed by the formation of Sn-Cl new bonds while in the presence of urea, the Sn-Ph bonds cleavage undergo with a deamination of the urea giving rise to the formation of Sn-N and Sn-Cl new bonds whose presence are ascertained by the Mossbauer parameters. The oxidation of tin (II) to tin (IV) as well as the coordination behavior of the oxonium, H3O+ cation is also noted in this work. In the reaction of triphenylphosphine oxide with SnCl2. 2H2O and nitric acid, we have obtained compounds in which tin has oxidized. The reactions between urea and SnPh3Cl are the site of a species exchange which can be explained by a deamination of urea and a dephenylation of SnPh3Cl Studies aimed at understanding the processes of this transformation still unknown leading to the isolation of aminochlorotin (IV) compounds and isolating their single crystals are being carried in our laboratory (LA.CHI.MI.A).