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Two paramagnetic octahedral Ni(II)-edta-type complexes, Ba[Ni(eddadp)]·6H2O(1) (eddadp) = ethylenediamine-N,N′-diacetate- N,N′-di-propionate ion) and Ba(Ni(edtp)]· 3H2O(bd2) (edtp = ethylenediamine-tetra-3-propionate Ion) have been prepared and characterized. The ligands used, forming β-alaninate rings, are likely to function as inexandentate with a larger metal ions. Because of the strain in the equatorial plane, as expected, the trans(O5) configuration of complex 1 was found to dominate and this geometry was verified crystallographically. The crystal is monoclinic with the space group C2/c, a = 11.091(3), b = 13.526(4), c = 28.064 A , β = 93.56(2)° and Z = 8 . The IR (carboxylatesregion) and electronic absorption spectra of these complexes are reported. There is no added multiplicity found in the electronic spectra of complexes that generally are seen for octahedral or pseudooctahedral Ni(II) complexes. Spectra of these complexes are discussed in comparison with those of the trans(O5)-[Ni(SS-edds)]2− complex (SS-edds = SS-ethylenediamine-N,N′-disuccinate ion) of known structure. The magnetic measurements are also reported for the complexes studied. Structural parameters and strain analysis data of M-edta-type complexes are discussed in relation to their octahedral distortion.

The octahedral copper(II) complexes of 1,3-propanediamine-N,N′-diacetic-N,N′-di-3-propionic acid (H41,3-pddadp) prepared in the region of pH 2 to 7 are hexadentates. Only one (trans(O6)) of the three geometrical isomers was found to dominate. The trans(O6)-Na2[Cu(1,3-pddadp)]·NaNO3·2H2O complex crystallizes in the space group P2/c of the monoclinic crystal system with a=9.231(2), b=11.736(14), c=10.150(2) A, β=109.33(2)° and Z=2. The conformations of the chelate rings are found to be envelope for the glycinate and skew-boat for the β-alaninate and 1,3-propanediamine rings. The complex is a tetragonally elongated octahedron (T ∼0.8) with C2 molecular symmetry. IR (carboxylate region) and electronic absorption spectra are assigned and discussed in relation to the structure of complexes. For hexadentate Cu(II) edta-type complexes of known structures the strain analysis is also discussed.

The crystal structure of Krans(O6)-[Co(1,3-pddadp)] · 3H2O(1,3-pddadp = 1,3-propanediamine-N,N'-diacetate-N,N'-di-3- propionate ion) was determined by single crystal X-ray diffraction techniques. The complex anion is a trans(O6) isomer in which the cobalt(III) ion is surrounded octahedrally by the two nitrogen and four oxygen atoms of 1,3-pddadp with the two-six-membered β-alaninate chelate rings in trans positions. This result confirms the assignment made on the basis of electronic absorption, circular dichroism and NMR spectroscopy. The complex Ktrans(O6)-[Co(1,3-pddadp)]·3H2O crystallizes in the space group P2 1 c of the monoclinic crystal system with unit cell parameters a = 9.298(2), b = 11.780(4), c = 16.771(5) A , β = 90.97(2)° and Z = 4 . The structure converged to R = 0.031 for 3019 reflections. Considerations of strains favor the trans(O6) isomer of [Co(1,3-pddadp)]−.

One of two geometrical isomers of the hexadentate cobalt(III) complex with 1,3-propanediamine- N , N , N ′-triacetate- N ′-3-propionate ion (1,3-pd3ap) has been prepared and resolved. The NMR, electronic absorption and circular dichroism (CD) spectra were used to characterize the complex. The 1 H and 13 C NMR spectra of this geometrical isomer indicate that its six-membered propionate chelate ring is bound axially to the cobalt(III) ion, trans (O 5 O o )-[Co(1,3-pd3ap)] − . The (−) 546 - trans (O 5 O o )-[Co(1,3-pd3ap)] − complex, with a positive CD peak at lowest energy in the first spin-allowed absorption band region is tentatively assigned the Λ absolute configuration. Spectral data for this complex are discussed in relation to those of other [Co(edta-type)] − complexes which vary the size of carboxylate arms in the same way but maintain a six-membered diamine ring.

In recent years, many edta-type ligands have been prepared and used to form hexadentate complexes with Co(III), Cr(III), and Rh(III). Absolute configurations have been determined by X-ray crystallography for representative complexes, substantiating assignments based on circular dichroism (CD) spectra. Within the first absorption band, the CD patterns for Co(III) complexes differ in energies of CD peaks relative to the absorption maximum, depending on the combinations of acetate and propionate arms. The overall pattern suggests that different combinations of three transitions usually appear. Some enlargement of chelate rings intended to relieve strain has been found to introduce other strain. Unexpected C-N bond cleavage for Cr(III) complexes of edta-type ligands with propionate arms led to the identification of conformational isomers.

Rhodium(III) complexes with the hexadentate ligand, 1,3-propanediamine-N,N′-diacetate-N,N′-di-3-propionate ion (1,3-pddadp) have been prepared, chromatographically separated and isolated into two geometrical isomers with respect to the NO chelate ring size (trans(O5) and trans(O5O6)). The 1H and 13C NMR and electronic absorption spectra were used to characterize the Rh(III) complexes. The 13C NMR spectra for two isomers of the corresponding [Co(1,3-pddadp)]- complex of known geometry (trans(O5O6) and trans(O6)) are also reported. The related edta-type complexes of known structure were used as references for assignment of complexes studied.

Cobalt(III)complexes with the hexadentate ligands, ethylenediamine-N,N,N′-triacetate-N′-3-propionate(ed3ap) and ethylenediamine-N,N-diacetate-N′,N′-di-3-propionate ion (u-eddadp), have been prepared, chromatographically separated and resolved. Only one of two geometrical isomers of the [Co(ed3ap)]− complex was isolated. A 1H NMR spectrum of this isomer,trans(O5)-[Co(ed3ap)]−, indicates that its six-membered propionate chelate ring is bound equatorially to the cobalt(III) ion. There is no similar structural variation possible for the hexadentate u-eddadp ligand. (−)546-trans(O5)-[Co(ed3ap)]− and (+ )546-[Co(u-eddadp)]− complexes with a positive CD peak at lowest energy in the first spin-allowed absorption band region are tentatively assigned the A absolute configuration. Spectral data of these complexes are discussed in relation to those of other [Co(edta-type)]− complexes of known structure.

Cobalt(III) complexes with the hexadentate ligand, 1,3-propanediamine-N,N′-diacetate-N,N′-di-3-propionate ion (1,3-pddadp) were prepared, chromatographically separated into two geometrical isomers with respect to the NO chelate ring size [trans(O5O6) and trans(O6)], and resolved. The 1H NMR, electronic absorption and circular dichroism (CD) spectra were used to characterize the complexes. The splitting of the T1g(Oh) band of the trans(O6-[Co(1,3-pddadp)]− complex indicates that the tetragonal field is enhanced, relative to the fields in other [Co(edta)]− -type complexes reported. The (+)546-trans(O5O6)-[Co(1,3-pddadp)]− and (+)546-trans(O6)-[Co(1,3- pddadp)]− complexes with a positive CD peak at lowest energy in the first spin-allowed d-d absorption band region are tentatively assigned the Λ absolute configuration. Preliminary results of a crystallographic study of the Ktrans(O6)-[Co(1,3-pddadp)]·3H2O confirm the assignments of geometrical isomers of the complexes.

A new hexadentate chromium(III) complex with ethylenediamine-N-acetic-N,N′,N′-tri-3-propionic acid [H4eda3p) is reported. Only one (trans(O5O6)) geometrical isomer of the [Cr(eda3p)]− complex ion was prepared and resolved into optical isomers. IR, electronic absorption and CD spectra were used for characterizing the complex. CD data in the region of the d-d transitions are discussed in comparison with those of other edta-type Cr(III) complexes of known configuration. The (−)589-isomer of the trans(O5O6)-[Cr(eda3p)]− complex, having a positive CD peak at lowest energy in the first spin-allowed d-d absorption band region, is tentatively assigned the Λ configuration.

The complexes, (+)589-Li[M(edtp)]·3H2O (MCo or Cr; edtp  ethylenediamine-N,N,N′,N′-tetra-3-propionate ion) crystallize in the space group P21 of the monoclinic crystal system with Z=2. For MCo, a=8.824(2), b=11.910(3), c=8.7282(2) A, β=95.03(1)° and for MCr, a=8.705(1), b=11.940(2), c=9.033(1) A, β= 94.19(1)°. The absolute configuration is △(λλ) for each complex where λ designates the conformation of the axial β-alaninate rings. Significant sources of strain are found and discussed for both complexes. The distortion from octahedral coordination in these [M(edtp)]− complexes is greater for Co(III) than it is for Cr(III) which is unusual compared to other [M(edtp)]−- type complexes. The absolute configurations of the complexes are consistent with earlier reports of their circular dichroism spectra.

The author describes his impressions of the efficiency of JCE's production of published articles.

Some simple copper compounds have unusual crystal structures. Cu3N is cubic with N atoms at centers of octahedra formed by 6 Cu atoms. Cu2O (cuprite) is also cubic; O atoms are in tetrahedra formed by 4 Cu atoms. These tetrahedra are linked by sharing vertices forming two independent networks without linkages between them. CuS (covellite) is hexagonal with two distinct roles for Cu and S. Some layers have linked hexagons formed by 3 S and 3 Cu and there are also layers of Cu atoms and layers of S atoms. The Cu atoms of Cu layers are in tetrahedra formed by one S of a Cu–S layer and three S of an S layer. Each S of an S layer is in a tetrahedron formed by 3 Cu of a Cu layer and an S of another S layer. The two bonded S atoms form S22- ions. Cu2S (high chalcocite) is hexagonal. There are layers of linked CuS3 hexagons and there are two Cu layers of tetrahedral sites. Cu atoms in tetrahedral layers are bonded to 3 S of one Cu–S layer and one S of another Cu–S layer. Structures are shown as unit cells and as polyhedra formed by 12 close-packed atoms in three layers to examine the roles of both atoms. Structures and roles of atoms are described by simple notation.

Decades ago Buerger described and later Palmer reviewed stuffed silica crystal structures widely used by mineralogists. Many publications and books have discussed common crystal structures in terms of close-packing of one set of atoms or ions (P sites) with other atoms or ions in tetrahedral (T) or octahedral (O) sites. Douglas and Ho described many minerals and compounds as having filled or partially filled layers in the regular pattern, PTOT. In the cubic close-packed (ccp) structure twelve neighbors of an atom form a cuboctahedron with six O and eight T voids. Filling all O sites as in NaCl, all T sites as in CaF2, or all O and T sites as in BiLi3 of a cuboctahedron formed by one set of ions gives structures with no loss of symmetry. More complex structures are described also. In the hexagonal close-packed (hcp) structure twelve neighbors of an atom form a 14-sided polyhedron described as a twinned cuboctahedron. For NiAs, the 14-sided polyhedron is formed by As atoms with Ni atoms filling O sites, but...

Preparation de complexes [Co(L)(H 2 O)Cl](ClO 4 ) 2 , [Co(L')](ClO 4 ) 3 et [CoL'']ClO 4 . Donnees RMN de 1 H

The complex ion [Co(1,3-pd3a)NO2]− (pd3a=trimethylenediamine-N,N,N′-triacetate ion) was prepared from equatorial-skew-[Co(1,3-pd3a)H2 O]. The absorption spectrum and the 13C NMR spectrum show the nitro product to be a polar isomer. The diamine backbone ring is believed to have the chair conformation.

NI(sen)2+ has been found to have utility as a template for macrocycle formation. Through reaction with acetone, an unusual ligand similar to cyclam but with an ethylenediamine substituent is formed. This macrocycle abbreviated TTT (13-[[(2′-aminoethyl)amino]methyl]-5,7,7,13-tetramethyl-1,4,8,11-tetraazacyclotetradec-4-ene) is capable of sexidentate or quadridentate coordination. The coordination type is dictated by pH. The complexes Ni(TTT)2+ and Ni(TTTH2)2+ are characterized by titration and by proton and carbon-13 nuclear magnetic resonance, electronic absorption, and infrared absorption spectroscopy.

The uns-cis-[Cr(1,3-pdda)(L)]− complexes (1,3- pdda = 1,3-propanediamine-N,N′-diacetate; L = oxalate or malonate) were prepared and resolved. The corresponding s-cis-[Cr(edda)L]− complexes (edda = ethylenediamine-N,N′-diacetate) have been partially resolved. The infrared absorption and circular dichroism (CD) spectra are reported. Rotational strengths of the uns-cis-[Cr(1,3-pdda)(L)]− complexes decrease with increasing chelate ring size of the bidentate anionic ligands. (−)589-[Co(en)2- (C2O4)]uns-cis-(−)546-[Cr(1,3-pdda)(mal)]·H2O crystallizes in the space group P21 of the monoclinic crystal system with a = 7.832(3), b = 14.207(6), c = 10.801(3) A, β = 98.46(3)° and Z = 2. In the anionic chromium complex, the six-membered diamine ring assumes the stable chair conformation; the equatorial glycinate ring is puckered; and the axial glycinate ring is in the ‘envelope’ conformation. The absolute configuration of the chromium complex ion is ΔΔΔΛ.

The absorption and circular dichroism (CD) spectra are reported for the free ligands and the Cu(II) and Fe(III) complexes of chiral 1,3-diketones (+)-3-hydroxymethylenecamphor ((+)-hmcH), (+)-3-acetylcamphor ((+)-3-acH), and the newly synthesized (+)-3-propionylcamphor ((+)-3-pcH). Only one diastereoisomer of the tris(1,3-diketonate) Fe(III) complexes seemed to be formed. The CD spectra give preference to one of two conflicting earlier assignments of transitions of Fe(III) 1,3-diketonate complexes. The absorption spectra for the bis(1,3-diketonate)Cu(II) complexes could be interpreted based on earlier work on Cu(II) 1,3-diketonates.

The uns-cis complexes [Co(TMDDA)(CO3)]−, [Co(TMDDA)(oxalate)]−, and [Co(TMDDA)(malonate)]− (TMDDA = trimethylenediamine-N,N′-diacetate ion) have been prepared and resolved. Their absorption and circular dichroism spectra are reported. Rotational strengths decrease with increasing chelate ring size for the bidentate ligands and for the larger diamine ring of the framework of the TMDDA complexes compared to those of EDDA.

New sexadentate Cr(III) complexes with (S, S)-ethylenediamine-N, N'-disuccinic acid (S, S-H4EDDS) and ethylenediamine-N, N'-diacetic-N, N'-di-3-propionic acid (H4EDDDA) are reported. With both ligands only trans(Os) geometrical isomers have been prepared. Infrared, electronic absorption, and CD spectra were used for characterizing the complexes. Because of the stereospecificity of the S, S-EDDS ligand the absolute configuration of the trans(O5)-Cr(S, S-EDDS)− is known. The (-)589-isomer of the trans(O5)-Cr(EDDDA)− complex, having a positive CD peak at lowest energy in the first spin-allowed d-d absorption band region, is tentatively assigned the A configuration, by comparison of its CD spectrum to the CD spectrum of the corresponding trans(Os)-Co(EDDDA)− and trans(O5)-Cr(S, S-EDDS)− complexes of known absolute configurations.

Two nitro, two aqua and a dinitro complex of ethylenediamine-N-N′-diacetato-N,N′-di-3-propionatocobaltate have been isolated. The four quinquedentate complexes have been resolved optically and their electronic absorption and CD spectra measured. Pmr spectra at 250 MHz have also been measured for the quinquedentate complexes as well as for the dinitro complex. Those of the quinquedentate complexes are quite complicated and difficult to interpret. 13C magnetic resonance spectra have been measured for all of these complexes and also for the sexidentate, trans(O5) and trans(O5O6) isomers of [Co(EDDDA)]−. The 13C spectra are much less complex and indicate that this technique can be useful as a tool for the study of stereochemistry of metal complexes with ligands containing several carbon atoms.

The complex ion [Co(mal)2(tn)]- (mal =malonate ion) and the corresponding complexes of trimethylenediamine (tn) containing the bidentate O-donor ligands C2O4 2- and acetylacetonate (acac) ions were prepared and resolved. Their circular dichroism (CD) spectra are compared with the data reported here for [Co(C2O4)2(I-chxn)]−, [Co(mal)2 (I-chxn)]−, [Co(mal)2(I-pn)]−, and [Co(acac)2(I-pn)]+ complex ions. The malonate complexes reveal greater splitting within the first absorption band region compared to C2O4 2- and acac, but lower net rotational strengths. The contributions to the CD spectra for the optically active ligands are comparable to those reported for other complexes. There is a much greater contribution from the optically active ligand in trans-cyclohexanediaminetetraacetatocobaltate ion than in the corresponding complex of 1,2-propanediaminetetracetatocobaltate ion.

Electronic absorption and CD spectra are reported for the sexidentate [Rh(1,3-pdta)]− complex (1,3-pdta = 1,3-propanediaminetetraacetate ion). The (-)D isomer of the [Rh(1,3-pdta)]− complex is assigned the A configuration by comparison of its CD spectrum to that of trans(O5)-[Rh(S, S-edds)]− known to have the A configuration from the stereospecificity of the S, S-edds ligand (S, S-edds = (S, S)-ethylenediamine-N, N-disuccinate ion).

Condensation reactions of three isomers of bis(diethylenetriamine)cobalt(III) with formaldehyde and ammonia were studied. The s-fac isomer gave a main product containing two molecules of the cyclic amine, 1,3,5,8-tetraazacyclodecane. It was unstable in acidic solution to give several decomposition products. The encapsulated complex in which all the nitrogens were attacked by formaldehyde could not be obtained. The main product of the u-fac isomer was a half encapsulated complex, i.e. , three of the four primary amino groups reacted with formaldehyde and ammonia to produce a cobalt(III) complex of 3-(7-amino-2,5-diazaheptyl)-1,3,5,8-tetraazacyclodecane. The mer isomer gave a complex of 1,4,7,9,11,14,17-heptaazaheptadecane, together with the same reaction product as the one from the u-fac isomer.

Biguanide-diamine mixed complexes of the type [Co(diamine)(Hbg)2]3 and [Co(diamine)2 (Hbg)]3+, where the diamines are 1,10-phenanthroline or 2,2′-dipyridyl, have been prepared and resolved. The absorption and circular dichroism (CD) spectra in water, 0.1 M NaOH aqueous solution, and ethanol are reported. Hydroxide ion affects the CD intensity mainly in the first absorption band region. A marked solvent effect of ethanol was also observed for both absorption and CD spectra especially in the first absorption band region. The absolute configurations for all of these complexes are assigned on the basis of their CD spectra.

The complexes Kcis-eq-[Co(ed3a)CN], Kcis-eq-[Co(med3a)CN)], and Ktrans-eq-[Co(ed3a)CN] were synthesized and characterized. The 1H and 13C NMR spectra obtained with a 300 MHz spectrometer are reported and compared to corresponding aqua and nitro complexes. The PMR spectra show good resolution for all protons, including those of the ethylenediamine backbone. The NMR spectra of the cyano complexes are most similar to those of the corresponding nitro complexes. The major changes in the 13C NMR spectra can be explained based on β-substituent effects involving the N-methyl group or conversion from the cis-eq to the trans-eq isomers. Racemic NH4[Co(ed3a)CN]·2H2O·0.5CH3OH was found to be triclinic, P-1 with the cell dimensions: a = 6.597(2), b = 7.783(4), c = 15.72(1) A, α = 88.63(5), β = 85.55(5), and γ = 69.89(4)°. There are two molecules in the unit cell.

The preparations and circular dichroism (CD) spectra of a series of bis(dimethylglyoximato)cobalt(III) complexes, each containing two asymmetric unidentate amines in trans positions, are reported. Tentative spectral assignments are made for the d-d region on the basis of effective D4h molecular symmetry. In all cases the rotational strengths observed for the aromatic amine complexes are larger than those observed for the alkyl amine complexes.

Electronic absorption and CD spectra are reported for the sexidentate complexes, trans(O5)-Rh(EDDDA)−, trans(O5 O6)-Rh(EDDDA)−, and trans(O5)-Rh(S,S-EDDS)− (EDDDA)=ethylenediamine-N,N′-di-3-propionate; S,S-EDDS=(S,S)-ethylenediamine-N,N′-disuccinate). Because of the sterospecific coordination of the S,S-EDDS ligand the absolute configuration of (+)D-trans(O5)-Rh(S,S-EDDS)− is known to be Λ. By comparison of their CD spectra to that of the (+)D isomer of trans(O5)-Rh(S,S-EDDS)−, the absolute configurations of the (−)DEDDDA complexes are assigned tentatively.

The protonation and stability constants of Ni(II), Cu(II), and Zn(II) complexes of a new sexidentate ligand, triethylenetetraamine-N 2,N 3-diacetic acid tetrahydrochloride (H2ttda·4HCl), have been determined using pH titration techniques at μ = 0.10. The complexes of ttda2- with Ni(II), Cu(II), and Zn(II) are more stable than those of edta and the Ni(II) and Zn(II) ttda complexes are more stable than those of penten.

Crystal structures of the novel complexes [Co- (edampda)] BF 4 ·H 2 O (edampda is N,N′ -bis(2-pyridylmethyl) ethylenediamine- N,N ′diacetate) (triclinic, P 1 , a =7.893(3), b =11.415(5), c =12.421(5) A, α=110.42(3)°, β=96.44(3)°, γ=92.10(3)°, V = 1038.8(6), Z =2, D calc =1.61, R =0.039 for 3481 observed reflections) and [Cu( uns -Hpenp)Cl 2 ]ClO 4 ( uns -Hpenp is N,N -bis(2-pyridylmethyl)-l-amino- ethylammonium) (orthorhombic, Pcam , a = 15.220(2), b =7.946(4), c =14.953(5) A, V = 1808.4(8), Z =4, D calc =1.75, R =0.051 for 1459 observed reflections) have been determined. Also, crystal structures of the complexes [Co(tpen)]- (ClO 4 ) 3 (tpen is N,N,N′,N′ -tetrakis(2-pyridylmethyl)- ethylenediamine) (monoclinic, P 2 1 / c , a =9.748(6), b =18.27(1), c =19.98(1) A, β=115.95(4)°, V = 3199(3), Z =4, D calc =1.62, R =0.101 for 2767 observed reflections), [Co(tppn)](ClO 4 ) 3 (tppn is N,N,N′,N′ -tetrakis(2-pyridylmethyl)- 1,2-propanediamine) (orthorhombic, P2 1 2 1 2 1 , a =9.849(4), b = 18.49(1), c =18.708(8) A, V =3406(2), Z =4, D calc =1.55, R =0.067 for 2804 observed reflections), and tppn (triclinic, P 1 , a =6.258(3), b = 9.570(4), c =10.629(5) A, α=77.85(4)°, β= 88.82(3)°, γ=74.22(3)°, V =598.3(5), Z =1, D calc =1.22, R =0.049 for 1548 observed reflections) have been determined. The degree of strain in the chelate rings of the cobalt and copper complexes is analyzed via ring angle sum deviations from ideal ring angle sums. The degree of strain in these complexes is compared to the smaller degree of strain in the structurally analogous complexes of [Co(edta)]−, [Co(penten)] 3+ and [Co(l-mepenten)] 3+ (edta is ethylenediamine- N,N,N′,N′ -tetraacetate; penten is N,N,N′,N′ -tetrakis(2-aminoethyl)ethylenediamine; mepenten is N,N,N′,N′ tetrakis(2-aminoethyl) -1,2-diaminopropane). The bond angles of the polypyridyl edampda, tpen and tppn complexes show large ligand-cobalt-ligand (LCoL) angles opposite to, and in the plane of, the ethylenediamine ring and systematically acute LCoL angles in some octahedral faces. The absolute configuration of (−) 589 -[Co(tppn)](ClO 4 )s is identified as ΔΛΔ by analysis of Friedel pairs collected with Cu Kα radiation, and this absolute configuration is correlated to negative Cotton effects for three transitions observed in the circular dichroism spectrum. Finally, the crystal structure of [Cu( uns -Hpenp)Cl 2 ]ClO 4 unambiguously confirms the synthesis of the novel ligand, uns -penp ( uns -penp is N,N -bis(2-pyridyl- methyl)ethylenediamine).

The hexadentate Cr(III) complex with ethylenediaminetetra-3-propionate (edtp) ion has been prepared and resolved. Infrared, electronic absorption and CD spectra were used to characterize the [Cr(edtp)]− complex. The CD data in the region of the d-d transitions are discussed in comparison with those of other edta-type Cr(III) complexes of known configuration. The (+)589−[Cr(edtp)]− complex, having a positive (dominant) CD peak in the first spin-allowed d-d absorption band region, is tentatively assigned the Δ configuration.