The Phenomenon of Intramolecular Attractive S---O Interactions: Synthesis and Structure of (1,10-Phenanthroline)copper(II) Complexes with Isonitroso-(4-methylthiazol-2-yl)acetamide and Isonitroso-(4-methylthiazol-2-yl)-(benzothiazol-2-yl)methanide

Abstract

Isonitroso-(4-methylthiazol-2-yl)acetamide H (L '), isonitroso-(4-methylthiazol-2-yl)(benzothiazol-2-yl)methanide H(L2) and their copper(II) complexes of composition [C u(Phen){L'}(C 104)] (1) and [Cu(Phen){L2}Cl]*C2H5 0 H (2) have been prepared. Crys tal and molecular structures of the complexes have been determined from X-ray diffractioon data (1: monoclinic, space group P2]/c, with a = 11.611(2), b = 10.259(2), c = 17.869(4) Ä, ß = 104.67(3)°, V = 2059.1(7) Ä3, Z = 4; R\ = 0.046 for the 2522 unique reflections with I > 2a(I). 2: triclinic, space group PI, with a = 8.351(1), b = 10.876(1), c = 14.891(2) Ä, a = 96.170(8)°, ß = 94.201(9)°, 7 = 106.721(9)°, V = 1280.1(2) A3, Z = 2; R\ = 0.034 for the 4038 unique reflections with I > 2a(I)).In the structure of 1 the coordination polyhedron of Cu2+ is a distorted square pyramid with an oxygen atom of the CIO4 counter anion in the apex (C u -0 2.505(3) A); in complex 2 the copper atom adopts fivefold coordination of a slightly distorted trigonal-bipyramidal geometry with a chlorine atom in the equatorial plane (Cu-Cl 2.3504(9) A). Ethanol of crystallization gives rise to a hydrogen bond at the chlorine atom. In both structures the oximic anions are coordinated to the metal center in a bidentate chelate manner via the nitrogen atom of the nitroso group and the carbonyl oxygen atom (1) or via the benzothiazole nitrogen atom (2) (Cu-O, Cu-N in the range 1.963(2) -2.031 (2) Ä). The thiazole group of the ligands takes no part in the coordination. The nitroso oxygen atoms possess short intramolecular contacts with thiazole sulphur atoms, with d(S-O) at 2.605(3) (1) and 2.676(3) A (2), which may be attributed to a strong intraligand interaction.

Demetallation of a Ni(II) tetraazamacrocyclic complex by cyanoxime resulting in the formation of a stereospecific trinuclear compound [Na(H2O)6]+[NaNi2L6]− (L = NC-C(NO)-C(O)NH )

“…This investigation represents part of the program of the studies of ampolydentate cyanoxime ligands [16][17][18][19], compounds that have the general formula NC-C(NOH)-R, where R is an electron withdrawing group. Cyanoximes form a variety of coordination compounds with interesting properties [20][21][22][23][24][25][26]. Several cyanoximes, such as 2-cyan-2-isonitrosoacetamide (later HACO, or amidecyanoxime), 2-cyan-2-isonitrosothioacetamide (later HTCO or thioamidecyanoxime) and their N,N-dimethylamide derivatives, previously have shown biological activity such as pesticide detoxifying [27,28], growth regulation [29][30][31][32] and anti-microbial [33,34].…”