Copper(II) and Cobalt(III) Complexes of a Mixed Secondary and Tertiary Nitrogen Donor Tetraaza Macrocycle. Crystal Structure of Aqua(7-methyl-7-nitro-1,5,9,13-tetraaza-bicyclo[11.2.2]heptadecane)copper(II) Perchlorate Hydrate

1989 ◽  
Vol 42 (11) ◽  
pp. 1859 ◽  
Author(s):  
LM Engelhardt ◽  
GA Lawrance ◽  
TM Manning ◽  
AH White

Reaction of (bis(3-aminopropyl) piperazine )copper(11) ion with nitroethane and formaldehyde in basic methanol results in the ready formation of (7-methyl-7-nitro-1,5,9,13- tetraazabicyclo [11.2.2] heptadecane )copper(11) ion in high yield. The perchlorate salt of the macrocyclic complex crystallizes in the orthorhombic space group Pbca, a 19.144(8), b 17.499(5), c 14.635(5) �, Z=8, with the copper ion in a square-pyramidal environment of four nitrogen donors and a water molecule. The Cu-secondary N and Cu-tertiary N distances are 2.044(8), 2.056(8) and 2.053(8), 2.072(8) � respectively, with the Cu-O distance 2.259(8)�. Reduction of the complex with Zn/ HCl yields the 7-methyl-1,5,9,13-tetraazabicyclo [l1.2.2]heptadecane-7-amine analogue, characterized as copper(II) and cobalt(III) complexes. The cobalt(III) complex contains the latter macrocycle as a quinquedentate ligand with the pendant primary amine coordinated trans to a chloride ion, identified as the only isomer by chromatography, and characterized by electronic and n.m.r. spectroscopy. Consequences of 'reinforcement' of the macrocycle by the extra ethane bridge are discussed.

1988 ◽  
Vol 41 (5) ◽  
pp. 773 ◽  
Author(s):  
P Comba ◽  
GA Lawrance ◽  
M Rossignoli ◽  
BW Skelton ◽  
AH White

Reaction of (3,7-dithianonane-1,9-diamine)copper(II) ion with nitroethane and formaldehyde in basic methanol gives the macrocyclic complex ion (6-methyl-6-nitro-1,II-dithia-4,8- diazacyclotetradecane )copper(II) in high yield. The complex as the perchlorate salt crystallizes in the monoclinic space group P21/n, a 15.008(5), b 8.606(3), c 17.967(4)Ǻ, β 113.79(2)�. The copper ion lies in a square plane of two nitrogen (average Cu-N 2.02 Ǻ) and two thioether (average Cu-S 2.295 Ǻ) donors, with perchlorate oxygens (Cu-O 2.46 and 2.70 Ǻ) in axial sites. Physical and structural properties of the CuIII complexes of the 14-membered cis-N2S2 macrocycle and the known analogous 14-membered N4-donor macrocycle 6-methyl-6-nitro-1,4,8,11- tetraazacyclotetradecane are compared.


1988 ◽  
Vol 66 (9) ◽  
pp. 2151-2156 ◽  
Author(s):  
Raj K. Chadha ◽  
Rajesh Kumar ◽  
Jaime Romero Lopez-Grado ◽  
Dennis G. Tuck

Cobalt(II) and nickel(II) thiolates, M(SR)2, can be prepared in high yield by the electrochemical oxidation of a metal anode in an acetonitrile or acetone solution of RSH (R = C6H5, o-CH3C6H4, 2-C10H7, 2,3,4,5-C6F4H; not all combinations). When 2,2-bipyridine or 1,10-phenanthroline (=L) is added to the electrolyte phase, the products are the adducts M(SR)2L2. In the case of Co(SC6H5)2(phen)2, aerial oxidation leads to the formation of the cobalt(III) cation [Co(SC6H5)2(phen)2]+, isolated as the perchlorate salt. X-ray crystallographic analysis showed that this cation has a cis-CoS2(N2)2 kernel.


1996 ◽  
Vol 51 (10) ◽  
pp. 1459-1463 ◽  
Author(s):  
Walter Frank ◽  
Guido J. Reiß

Bis(1,2-diammoniopropane) hexachlororhodate(III) chloride, [H3N-CH(CH3)-CH2-NH3]2 [RhCl6]Cl (1) has been obtained by the reaction of rhodium(III) chloride with rac-1,2- diammoniopropane dihydrochloride in hydrochloric acid solution. The quasi-ternary compound, which crystallizes in the orthorhombic space group Pbca (a - 11.0007(13) Å, b = 22.181(2) A, c = 14.638(2) A, V = 3571.7(7) Å3, \ T = -120 °C, Z - 8) contains two crystallographically independent 1,2-diammoniopropane ions beside one hexachlororhodate and one chloride ion. One of the cations shows a R/S-S/R-disorder of enantiomeric pairs in the centrosymmetric crystal lattice. The packing scheme is determined by a complex framework of hydrogen bonds.


1989 ◽  
Vol 42 (7) ◽  
pp. 1045 ◽  
Author(s):  
LM Engelhardt ◽  
EA Keegan ◽  
GA Lawrance ◽  
AH White

The complexes [Co( tren )(P2O7H2)] (ClO4).H2O, [Co( tren )(P3010H3)] (ClO4) (tren = N,N-bis(2- aminoethyl )ethane-1,2-diamine) and [Co( cyclen )(P2O7H2)](ClO4)(cyclen = 1,4,7,10-tetraazacy-clododecane ) have been prepared and characterized. The complex [Co( tren )(P207H2)](C104).H20 crystallized in the monoclinic space group P21/n,a 10.655(3), b 14.675(5), c 11.260(4) � , β 98.49(3) for a single-crystal structure determination R was 0.041 for 4043 'observed' reflections. Despite the presence of a primary and a tertiary nitrogen donor in the plane of the cobalt and the phosphate oxygen donors, bond distances to Co-N(primary) and Co-N(tertiary) at 1.926(3) and 1.924(3) � respectively are equivalent, as are the Co-O distances of 1.940(2) and 1 .943(3) to the N(primary) and N(tertiary) respectively. Axial Co-N(primary) bonds (av. 1.952 A) are elongated compared with the in-plane N(primary), and the axial N-Co-N angle is distorted (171.6�). The hydrolysis of the diphosphate and triphosphate complexes at pH 7.3 in the presence of an assisting complex, [Co( tn )2(OH2)(OH)]2+ ( tn = propane-1,3-diamine) or [Co( tren )(OH2)(0H)]2+, was followed by 31P n.m.r. spectroscopy, and rate enhancements of up to about 104 compared with free polyphosphate were observed, with the diphosphato complexes being least sensitive to cleavage by added complex. Intermediates in which the polyphosphate bridges two metal centres are apparently involved; the inability of [Pd(en)(0H2)2]2+(en= 1,2-ethanediamine) to enhance cleavage is consistent with this, since this ion does not form complexes with polyphosphates. [Co( tren )(ATP)](ATP=adenosine triphosphate ) was also prepared but not isolated; assisted hydrolysis with [Co( tren )(OH2)(OH)]2+ is about 104 faster than unassisted hydrolysis of free ATP under similar conditions.


2021 ◽  
Vol 76 (3-4) ◽  
pp. 193-199
Author(s):  
Muhammad Said ◽  
Sadia Rehman ◽  
Muhammad Ikram ◽  
Hizbullah Khan ◽  
Carola Schulzke

Abstract Three guanidine-derived tri-substituted ligands viz. N-pivaloyl-N′,N″-bis-(2-methoxyphenyl)guanidine (L1), N-pivaloyl-N′-(2-methoxyphenyl)-N″-phenylguanidine (L2) and N-pivaloyl-N′-(2-methoxyphenyl)-N″-(2-tolyl)guanidine (L3) were reacted with Cu(II) acetate to produce the corresponding complexes. The significance of the substituent on N″ for the resulting molecular structures and their packing in the solid state has been studied with respect to the structural specifics of the corresponding Cu(II) complexes. The key characteristic of the guanidine-based metal complexation with Cu(II) is the formation of an essentially square planar core with an N2O2 donor set. As an exception, in the complex of L1, the substituent’s methoxy moiety also interacts with the Cu(II) center to generate a square-pyramidal geometry. The hydroxyl groups of the imidic acid tautomeric forms of L1–L3, in addition to N″, are also bonded to Cu(II) in all three complexes rather than the nitrogen donor of the guanidine motif.


2021 ◽  
pp. 1-3
Author(s):  
Carina Schlesinger ◽  
Edith Alig ◽  
Martin U. Schmidt

The structure of the anticancer drug carmustine (1,3-bis(2-chloroethyl)-1-nitrosourea, C5H9Cl2N3O2) was successfully determined from laboratory X-ray powder diffraction data recorded at 278 K and at 153 K. Carmustine crystallizes in the orthorhombic space group P212121 with Z = 4. The lattice parameters are a = 19.6935(2) Å, b = 9.8338(14) Å, c = 4.63542(6) Å, V = 897.71(2) ų at 153 K, and a = 19.8522(2) Å, b = 9.8843(15) Å, c = 4.69793(6) Å, V = 921.85(2) ų at 278 K. The Rietveld fits are very good, with low R-values and smooth difference curves of calculated and experimental powder data. The molecules form a one-dimensional hydrogen bond pattern. At room temperature, the investigated commercial sample of carmustine was amorphous.


2015 ◽  
Vol 70 (3) ◽  
pp. 191-196 ◽  
Author(s):  
Olaf Reckeweg ◽  
Francis J. DiSalvo

AbstractThe new compounds LiK[C(CN)3]2 and Li[C(CN)3]·½ (H3C)2CO were synthesized and their crystal structures were determined. Li[C(CN)3]·½ (H3C)2CO crystallizes in the orthorhombic space group Ima2 (no. 46) with the cell parameters a=794.97(14), b=1165.1(2) and c=1485.4(3) pm, while LiK[C(CN)3]2 adopts the monoclinic space group P21/c (no. 14) with the cell parameters a=1265.7(2), b=1068.0(2) and c=778.36(12) pm and the angle β=95.775(7)°. Single crystals of K[C(CN)3] were also acquired, and the crystal structure was refined more precisely than before corroborating earlier results.


1984 ◽  
Vol 62 (3) ◽  
pp. 601-605 ◽  
Author(s):  
Masood A. Khan ◽  
Clovis Peppe ◽  
Dennis G. Tuck

The crystal structure of the title compound has been determined by the heavy atom method. The crystals are orthorhombic, space group Pbca, with unit cell dimensions a = 22.795(3) Å, b = 17.518(2) Å, c = 12.396(3) Å, Z = 8; R = 0.0409 for 1527 unique "observed" reflections. The structure is disordered, with each halogen site (X) occupied by 75% Br, 25% I. The molecule consists of two X2(tmen)In units (tmen = N,N,N′,N′-tetramethylethanediamine) with distorted trigonal bipyramidal geometry, joined by an In—In bond 2.775(2) Å in length.


1988 ◽  
Vol 43 (5) ◽  
pp. 567-570 ◽  
Author(s):  
Peter Hoffmann ◽  
Franz-Josef Hermes ◽  
Rainer Mattes

Abstract The reaction of 1-thia-4,7-diazacyclononane (C6H14N2S = L) with salts containing Tl(I) and (III), In(III) and Pb(II) ions yields 1:1 complexes, which can be crystallized as halide or Perchlorate salts. The structure of [LPb][PbBr4] (5) has been determined: Crystal data: orthorhombic, space group P212121, a = 853.2(6), b = 1000.1(4), c = 1860(1) pm, Z = 4. Pb2+ in the [LPb]2+ cation is seven-coordinated by the tridentate ligand and a square of four Br- ions. The Pb-S distance, 286.0(5) pm, is rather short, the lone pair stereochemically activ. The PbBr4- ions are polymeric with octahedrally coordinated lead(II) atoms.


2017 ◽  
Vol 46 (13) ◽  
pp. 4452-4460 ◽  
Author(s):  
V. H. Nissinen ◽  
I. O. Koshevoy ◽  
T. T. Pakkanen

Chelating oxygen and nitrogen donor ligands (1,2-dimethoxyethane, 1,3-dimethoxypropane, and N,N′-diethylethylenediamine) are found to dictate the crystal structure formation of MgCl2, the important support component of a polymerization catalyst.


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