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By a selective exchange of ligand Br by Cl, a series of nonstoichiometric bromo-chloro-pyridine- molybdenum(III) octahedral compounds of the type (cat)[MoBraCl(4-a)py2] (cat = pyH, a = 3–1 (1, 4, 7)); cat = [(C2H5)3NH], a = 2.744 (2); cat = Rb, a = 2.278 (5); cat =[(C6H5)4)As], a = 1.258 (8) and [MoBraCl(3–a)py3] (a = 2–1 (3, 6)) have been prepared and characterized. Owing to great similarity of the powder diffraction patterns and IR spectra of compounds mer- [MoBraCl(3-a)py3] (a = 3–0) with the known monoclinic modification in the space group P21/c and compounds [MoBraCl(3-a)py3] (a = 2-1 (3, 6)), the same type of crystal lattice was confirmed. Isostructurality was observed also for the orthorhombic trans-(pyH)[MoBr4py2]](Pnma) and compounds 1 and 4, while compound 7 is isostructural to trans-(pyH)[MoCl4py2]. X-ray crystallographic analyses of 2, 5 and 8, obtained by recrystallization of (pyH)[MoBraCl(4-a)py2] (a = 3–1) with different cations, were performed. In these compounds, MoIII is octahedrally coordinated with four halogenido ions at distances 2.4953(6)–2.5920(10) Å and two pyridine molecules at distances 2.195(4)-2.220(4) Å. Trans oriented pyridine rings in compounds 5 and 8 are co-planar, while deviation from co-planarity was noticed for compound 2 (8.9(3)°). The stoichiometry of four coordinated Br and Cl atoms in these compounds is not ideal, since the structure analysis results for 2, 5 and 8 show a mixed occupancy of crystallographic sites; thus, refined population parameters for both atoms (Br and Cl) were calculated., Selektivnom zamjenom bromovoga liganda klorovim dobijena je i karakterizirana serija nestehiometrijskih bromo-kloro-piridin-MoIII kompleksa tipa (cat)[MoBraCl(4–a)py2] (cat = pyH, a = 3–1 (1, 4, 7); cat = [(C2H5)3NH], a = 2.744 (2); cat = Rb, a = 2.278 (5); cat = [(C6H5)4As], a = 1.258 (8)) i [MoBraCl(3–a)py3] (a = 2–1 (3, 6)). Uslijed velike sličnosti difraktograma praha i IR spektara spojeva mer-[MoBraCl(3–a)py3] (a = 3–0) poznate monoklinske modifikacije u prostornoj grupi P21/c i spojeva [MoBraCl(3–a)py3] (a = 2–1 (3, 6)), potvr|en je isti tip kristalne re{etke. Opa`ena je izostrukturnost rompskoga trans-(pyH)[MoBr4py2] (Pnma) i spojeva 1 i 4, dok je spoj 7 izostrukturiran s trans-(pyH)[MoCl4py2]. Načinjena je rentgenska strukturna analiza spojeva 2, 5 i 8 dobijenih prekristalizacijom (pyH)[MoBraCl(4–a)py2] (a = 3–1) s različitim kationima. U tim je spojevima MoIII oktaedarski koordiniran s četiri halogenidna iona na udaljenostima 2.4953(6)–2.5920(10) Å i dvije molekule piridina na udaljenostima 2.195(4)–2.220(4) Å. Trans orijentirani piridinski prstenovi u spojevima 5 i 8 su koplanarni dok je kod spoja 2 ustanovljena devijacija od koplanarnosti (8.9(3)°). Strukturnom analizom utočnjeni su faktori zauzetosti četiri koordinirana atoma (Br, Cl) u spojevima 2, 5 i 8. Na|eno je da su navedeni kristalografski položaji zauzeti atomima Cl i Br u nestehiometrijskome omjeru.

Ammonium hydrogen maleate, NH4+C4Ha04- crystallizes in the orthorhombic system with a = 0.4616(1), b = 0.8085(2), c = 1.6410(5) nm, Z = 4 in space group Pbcm, and is isostructural with the analogous potassium salt. The crystal structure has been refined from diffracton1eter data to conventional R and Rw of 0.052 and 0.065 for 690 reflexions [I> 3 a (I)]. Minor changes in the crystal struc-· ture were observed due to formation of N-H · · · 0 hydrogen bonds.

The synthesis, some spectroscopic properties and X-ray structure analysis of the new copper(II)dichloride complexes of 3-hydroxymethyl- (1), and 3-acetoxymethyl- (2) derivatives of 7-bromo-1, 3-dihydro-1-methyl-2H-1, 4-benzodiazepin-2-one are presented. 1, 4-Benzodiazepine-2-one derivatives are well known CNS active compounds. Well documented properties of nitrogen ligands to form metal complexes possessing biological activity even higher than the free ligands, prompted us to prepare copper-complexes of 1 and 2. During the crystal growth of complexes, unexpected chemical transformations occurred. Mechanisms of these chemical transformations will be discussed. The complexes were prepared by reaction of copper(II)chloride dihydrate and benzodiazepine ligands in 1:1 metal to ligand ratios in two different solvents: ligand 1 in absolute ethanol and ligand 2 in a mixture of dichloromethane and ethanol. In the first case two kinds of crystalline complexes were obtained: complex A (green) and complex B (black). X-ray structure analysis has shown that green complex (monoclinic, P21/n ; a= 8.48Ĺ ; b =15.05Ĺ ; c=17.47Ĺ ; b =91.64°) (Fig. 1) contains the rearranged benzodiazepine ligand as the 3-hydroxy substituted derivative of 1. The Cu(II)complex exhibits five-fold coordination in the shape of a square pyramid. The crystal structure analysis of the black complex B (Fig. 2) has shown an unprecedented transformation of benzodiazepine ligand to quinazole, whith square-planar coordiantion of Cu(II) (monoclinic, P21/n ; a=10.073 Ĺ, b=13.027 Ĺ, c=14.020 Ĺ, b=105.71°) The 3-acetoxymethyl-substituted ligand (derivative 2) did not exhibit chemical transformation upon metal complexation. In the complex C (monoclinic, P21/n ; a=10.815 Ĺ, b=9.072 Ĺ, c=19.985 Ĺ, b=98.64°) Cu(II) is coordinated by two nitrogen atoms and two chlorine atoms (Fig. 3). The five-fold coordination is completed by oxygen of a carbonyl group from the neighbouring ligand molecule. By this bridging an infinite chain is formed.