Salomé Delgado

Single layers of a multifunctional laminar Cu(I,II) coordination polymer

A multifunctional bidimensional mixed-valence copper coordination polymer [Cu2Br(IN)2]n (IN = isonicotinato) has been characterized in crystal phase and isolated on graphite surface as single sheets.

Solvent‐Induced Delamination of a Multifunctional Two Dimensional Coordination Polymer

A coordination polymer is fully exfoliated by solvent-assisted interaction only. The soft-delamination process results from the structure of the starting material, which shows a layered structure with weak layer-to-layer interactions and cavities with the ability to locate several solvents in an unselective way. These results represent a significant step forward towards the production of structurally designed one-molecule thick 2D materials with tailored physico-chemical properties.

Electrical conductivity and luminescence in coordination polymers based on copper(I)-halides and sulfur-pyrimidine ligands.

The solvothermal reactions between pyrimidinedisulfide (pym(2)S(2)) and CuI or CuBr(2) in CH(2)Cl(2):CH(3)CN lead to the formation of [Cu(11)I(7)(pymS)(4)](n) (pymSH = pyrimidine-2(1H)-thione) (1) and the dimer [Cu(II)(μ-Br)(Br)L](2) (L = 2-(pyrimidin-2-ylamino)-1,3-thiazole-4-carbaldehyde) (2). In the later reaction, there is an in situ S-S, S-C(sp(2)), and C(sp(2))-N multiple bond cleavage of the pyrimidinedisulfide resulting in the formation of 2-(pyrimidin-2-ylamino)-1,3-thiazole-4-carbaldehyde. Interestingly, similar reactions carried out just with a change in the solvent (H(2)O:CH(3)CN instead of CH(2)Cl(2):CH(3)CN) give rise to the formation of coordination polymers with rather different architectures. Thus, the reaction between pym(2)S(2) and CuI leads to the formation of [Cu(3)I(pymS)(2)](n) (3) and [CuI(pym(2)S(3))] (pym(2)S(3) = pyrimidiltrisulfide) (4), while [Cu(3)Br(pymS)(2)](n) (5) is isolated in the reaction with CuBr(2). Finally, the solvothermal reactions between CuI and pyrimidine-2-thione (pymSH) in CH(2)Cl(2):CH(3)CN at different ratios, 1:1 or 2:1, give the polymers [Cu(2)I(2)(pymSH)(2)](n) (6) and [Cu(2)I(2)(pymSH)](n) (7), respectively. The structure of the new compounds has been determined by X-ray diffraction. The studies of the physical properties of the novel coordination polymers reveal that compounds 3 and 5 present excellent electrical conductivity values at room temperature, while compounds 1, 3, and 5-7 show luminescent strong red emission at room temperature.

Synthesis and electrochemical study of cobalt carbonyl complexes of trimethylsilyl-substituted 1,3,5-triethynylbenzene

Treatment of 1,3,5-tris(trimethylsilylethynyl)benzene or 1,3,5-triethynylbenzene with Co 2 (CO) 8 or Co 2 (CO) 6 (dppm) produced the formation of substituted ethynylcobalt complexes with one, two or three Co 2 (CO) 6 or Co 2 (CO) 4 (dppm) units, [{X 3 (Co 2 (CO) 6 )C 2 } n (XCC) m (1,3,5-C 6 H 3 )] (X=H or SiMe 3 ) ( n =1, 2 or 3; m =3− n ) and [{SiMe 3 (Co 2 (CO) 4 dppm)C 2 } n (SiMe 3 CC) m (1,3,5-C 6 H 3 )] ( n =1 or 2; m =3− n ), in a high yield. Desilylation of the non-metallated alkynes in [{SiMe 3 (Co 2 (CO) 4 dppm)C 2 }(SiMe 3 CC) 2 (1,3,5-C 6 H 3 )] occurred on treatment with KOH. Electrochemical results provide evidence for communication between the C 2 Co 2 centres. Crystals of [{SiMe 3 (Co 2 (CO) 4 dppm)C 2 } 2 (SiMe 3 CC)(1,3,5-C 6 H 3 )] suitable for single-crystal X-ray diffraction were grown and the molecular structure of this compound is discussed.

Alkynyl cobalt complexes. An electrochemical study

Abstract The preparation and characterisation of the complexes Co2(CO)5(PMe3)(μ-η2-Me3SiC2CCSiMe3) (2) and Co2(CO)4(PMe3)2(μ-η2-Me3SiC2CCSiMe3) (3) are described. A comparative electrochemical study of the complexes Co2(CO)6−nLn(μ-η2-Me3SiC2CCSiMe3) (n=0 (1); n=1, L=PMe3 (2); n=2, L=PMe3 (3), PPh2Me (4), dppa (5), dppm (6)) is presented by means of the cyclic and square-wave voltammetry techniques. Substitution of CO by phosphine ligands transforms the Co2C2 redox centre from a readily reducible to an easily oxidisable centre and contributes to the stabilisation of the Co–Co bond increasing the lifetime of the radical cations and anions.

SYNTHESIS AND CHARACTERIZATION OF NEW TRANSITION METAL DIYNYL COMPLEXES

The reaction of (η 5 -C 5 H 5 )Mo(CO)(dppe)Cl with LiCCCCSiMe 3 yielded (η 5 -C 5 H 5 )(CO)(dppe)MoCCCCSiMe 3 ( 1b ) and, as a by-product (η 5 -C 5 H 5 )Mo(CO)(dppe)Br ( 1a ). Treatment of 1b with 0.2 equivalents of tetrabutylammonium fluoride or (η 5 -C 5 H 5 )Mo(CO)(dppe)Cl with HCCCCH gave the terminal butadiyne complex (η 5 -C 5 H 5 )(CO)(dppe)MoCCCCH ( 2 ). Complex 2 was deprotonated with sec -BuLi or lithium diisopropylamide, and the resulting anion (η 5 -C 5 H 5 )(CO)(dppe)MoCCCCLi ( 3 ) was trapped with Me 3 SiCl to regenerate 1b . The synthesis of Co 2 (CO) 4 L 2 (μ-η 2 -Me 3 SiC 2 CCSiMe 3 ) (L 2 =dppa 4 , 2PPh 2 Me 5 ) compounds can be achieved by two methods: from Co 2 (CO) 6 (μ-dppa) by reaction with Me 3 SiCCCCSiMe 3 in 1:1 ratio to yield 4 , or from Co 2 (CO) 6 (μ-η 2 -Me 3 SiC 2 CCSiMe 3 ) by reaction with dppa (1:1 ratio) and PPh 2 Me (1:2 ratio) to yield 4 and 5 , respectively. When the Co 2 (CO) 4 (μ-dppa)(μ-η 2 -Me 3 SiC 2 CCSiMe 3 ) complex was treated with more Co 2 (CO) 6 (μ-dppa) the green di-substituted complex [Co 2 (CO) 4 (μ-dppa)] 2 (μ-η 2 :μ-η 2 -Me 3 SiC 2 C 2 SiMe 3 ) ( 6 ) was obtained. Desilylation of 4 with Bu 4 NF gave Co 2 (CO) 4 (μ-dppa)(μ-η 2 -Me 3 SiC 2 CCH) ( 7 ). All compounds synthesized have been characterized by analytical and spectroscopic data (IR, 1 H-, 31 P-, 13 C-NMR, MS). In addition, compounds 1a and 4 were characterized by X-ray structure analysis.

Reactions of Co2(CO)8 with potentially polydentate phosphines

Abstract Co2(CO)8 reacts with potentially polydentate phosphines such as Ph2Ppy (2-(diphenylphosphino)pyridine), t-dppv (trans-1,2-vinylenebis(diphenylphosphine)), dppa (bis(diphenylphosphino)amine) and dpmp (bis((diphenylphosphino)methyl)phenylphosphine) to give Co2(CO)6L2 (L=Ph2Ppy and t-dppv), Co2(CO)6(dppa) and Co2(CO)5(dpmp) where the ligands behave as mono-, di- and tridentate, respectively, via the ionic intermediates [Co2(CO)3L2][Co(CO)4] (L=Ph2Ppy and t-dppv) and [Co(CO)3 P P ][Co(CO)4] ( P P =dppa and dpmp). All the compounds have been characterized by elemental analysis, IR, electronic, 1H and 31P NMR spectroscopy.

Reversible recrystallization process of copper and silver thioacetamide-halide coordination polymers and their basic building blocks†

Three-dimensional [CuX(TAA)]n (X = Br (1), I (2)) and bi-dimensional [AgX(TAA)]n (X = Cl (3), Br (4)) coordination polymers have been isolated by the direct synthesis from copper(I) and silver(I) halides and thioacetamide (TAA). These are multifunctional materials showing electrical conductivity (values at room temperature ranging from 7 × 10−6 to 2 × 10−9 S cm−1) and luminescence in the blue region. The unusual solubility of 1–4 in different solvents and the recrystallization process observed for 1 and 2 in acetonitrile and for 3 and 4 in pyridine have been measured. We show preliminary results of the processability of 2 on glass for the production of organized thin films. These results are very attractive for the processability of coordination polymers in materials science and nanoscience.

Luminescent Thermochromism of 2D Coordination Polymers Based on Copper(I) Halides with 4‐Hydroxythiophenol

Solvothermal reactions between copper(I) halides and 4-mercaptophenol give rise to the formation of three coordination polymers with general formula [Cu3 X(HT)2 ]n (X=Cl, 1; Br, 2; and I, 3). The structures of these coordination polymers have been determined by X-ray diffraction at both room- and low temperature (110 K), showing a general shortening in Cu-S, Cu-X and Cu-Cu bond lengths at low temperatures. 1 and 2 are isostructural, consisting of layers in which the halogen ligands act as μ3 -bridges joining two Cu1 and one Cu2 atoms whereas in 3 the iodine ligands is as μ4 -mode but the layers are quasi-isostructural with 1 or 2. These compounds show a reversible thermochromic luminescence, with strong orange emission for 1 and 2, but weaker for 3 at room temperature, whereas upon cooling at 77 K 1 and 2 show stronger yellow emission, and 3 displays stronger green emission. DFT calculations have been used to rationalize these observations. These results suggest a high potential for this novel and promising stimuli-responsive materials.

Electrochemical study of methylfulvalene and methylcyclopentadiene molybdenum complexes

Abstract The product of the synthesis of ( η 5 : η 5 -(C 5 H 3 Me) 2 )Mo 2 (CO) 6 ( 1 ) is reported as a mixture of six stereoisomers, the ratio of which has been unambigously assigned using homonuclear two dimensional correlation spectroscopy (COSY and NOESY). The reaction of Li 2 [( η 5 : η 5 -(C 5 H 3 Me) 2 )Mo 2 (CO) 6 ] ( 2 ) with IMe yields ( η 5 : η 5 -(C 5 H 3 Me) 2 )Mo 2 (CO) 6 Me 2 ( 3 ) and that of 1 with I 2 yields ( η 5 : η 5 -(C 5 H 3 Me) 2 )Mo 2 (CO) 6 I 2 ( 4 ). The electrochemical behaviour of 1 , 3 , and 4 is reported and compared with analogous complexes where other substituents are present on the fulvalene rings. Electronic communication through the fulvalene ligand seems to take place in 4 . The related compounds [( η 5 -C 5 H 4 R)Mo(CO) 3 ] 2 (R=Me ( 5 ), H ( 9 )), ( η 5 -C 5 H 4 R)Mo(CO) 3 Me (R=Me ( 7 ), H ( 10 )) and ( η 5 -C 5 H 4 R)Mo(CO) 3 I (R=Me ( 8 ), H ( 11 )) have been synthesized in order to compare their electrochemical behaviour with the fulvalene analogous.