coo

What are the advantages aluminum cooking utensil

Stainless steel tableware and kitchenware of rural hardware market is still in its infancy, mainly relying on the grocery store, hardware stores and other sales channels, products generally belong to the low-end, the brand is more...




coo

China signs cooperation agreements with OECD and joins OECD Development Centre

In a historic visit by Chinese Premier Li Keqiang to the OECD in Paris, the People’s Republic of China today decided to enhance longstanding collaboration with the OECD and to join the OECD Development Centre.




coo

Iceland: Better coordination among authorities needed to tackle foreign bribery, says OECD

Iceland must do more to ensure its law enforcement authorities are coordinated and adequately resourced to investigate and prosecute economic and financial crime, including foreign bribery, says the OECD in a new report.




coo

Countries should focus on labour market policies to help refugees and improve coordinated actions to tackle illegal immigration

Migration flows to OECD countries have dropped slightly for the first time since 2011, with around 5 million new permanent migrants in 2017, down from 5.3 million in 2016. This trend is mainly due to a significant decrease in new asylum applications, with 1.2 million applications in 2017 compared to 1.6 million in 2016, according to a new OECD report.




coo

Is there a Need for Cooperation on National Climate Change Policies?

Climate policy and competitiveness issues have created a new need for international co-ordination, beyond the scope of our current frameworks. There is no need to trade economic growth for environmental stringency. Environmentally stringent policies are an incentive for greater efficiencies which leading edge companies can easily achieve.




coo

OECD’s Gurría reaffirms need for global cooperation amid progress at G20 Summit

International cooperation is now more critical than ever, OECD Secretary-General Angel Gurría said following a G20 Leader’s Summit marked both by controversy but also advances on a range of policies to tackle global challenges.




coo

Clean power for a cool planet: Electricity infrastructure plans and the Paris Agreement - Environment Working Paper

Meeting the temperature goals of the Paris Agreement requires a transformational change in our infrastructure systems. This working paper aims to shed light on the extent to which current electricity generation projects under construction at the global level - the "pipeline" - are consistent with what a low-carbon transition requires.




coo

Is there a Need for Cooperation on National Climate Change Policies?

Climate policy and competitiveness issues have created a new need for international co-ordination, beyond the scope of our current frameworks. There is no need to trade economic growth for environmental stringency. Environmentally stringent policies are an incentive for greater efficiencies which leading edge companies can easily achieve.




coo

OECD, ILO call on G20 labour ministers to reinforce cooperation

Joint statement by ILO Director-General Guy Ryder and OECD Secretary-General Angel Gurría on the occasion of the G20 Labour and Employment Ministers’ Meeting, Moscow, 18-19 July 2013




coo

OECD and Italian government step up cooperation on boosting jobs and local development - Renewal of the OECD LEED Trento Centre's mandate

The OECD and the Italian government are stepping up cooperation to ensure effective implementation of local development strategies to boost jobs, encourage entrepreneurship and increase social inclusion. An agreement, to be signed in Rome on 1 December 2015, will renew the mandate of the OECD Trento Centre for Local Development and establish a satellite office in Venice.




coo

Countries should focus on labour market policies to help refugees and improve coordinated actions to tackle illegal immigration

Migration flows to OECD countries have dropped slightly for the first time since 2011, with around 5 million new permanent migrants in 2017, down from 5.3 million in 2016. This trend is mainly due to a significant decrease in new asylum applications, with 1.2 million applications in 2017 compared to 1.6 million in 2016, according to a new OECD report.




coo

Iceland: Better coordination among authorities needed to tackle foreign bribery, says OECD

Iceland must do more to ensure its law enforcement authorities are coordinated and adequately resourced to investigate and prosecute economic and financial crime, including foreign bribery, says the OECD in a new report.




coo

OECD and China expand cooperation in PISA education programme

The OECD and China have announced that they will expand their cooperation in PISA, following the successful implementation of PISA 2009 and 2012 in Shanghai.




coo

OECD and Italian government step up cooperation on boosting jobs and local development - Renewal of the OECD LEED Trento Centre's mandate

The OECD and the Italian government are stepping up cooperation to ensure effective implementation of local development strategies to boost jobs, encourage entrepreneurship and increase social inclusion. An agreement, to be signed in Rome on 1 December 2015, will renew the mandate of the OECD Trento Centre for Local Development and establish a satellite office in Venice.





coo

MPs launch inquiry into e-scooter safety ahead of trials amid road chaos fears

The Department for Transport (DfT) last month revealed the electric scooters, capable of 30mph, will be trialled in select cities as part of plans for a 'transport revolution'.




coo

Karlie Kloss eats a cookie on the floor in her wedding dress

The model, 27, posted several throwbacks on Friday, including one of her eating a cookie on the floor on her wedding day to Joshua Kushner.




coo

Granit Xhaka says he'd not felt such 'hatred' as he lost cool and told Arsenal fans to 'f*** off'  

The midfielder's career at the Emirates looked to be over after he was stripped of the captaincy following his altercation with fans in the 2-2 draw with Crystal Palace.




coo

How coolies of Hatia responded to our call for help




coo

Apple CEO Tim Cook on India, Steve Jobs, missteps and more

Apple CEO Tim Cook is a man of few words. In an interview to Washington Post, the usually reticent CEO of one of the world's most valuable company talked about a number of things including the 'enormous India opportunity', Steve Jobs, mistakes made during his tenure so far and much more.




coo

Redditors Did a Lockdown Cooking Contest and Here Are the Best Recipes

The best three photos will be decided on the basis of the votes on the posts.




coo

Zoa Morani Donates Blood For Covid-19 Plasmatherapy, Says "It Felt Super Cool"

Actress Zoa Morani, who along with sister Shaza and father, film producer Karim Morani recovered from Covid-19 in April donated her blood for plasmatherapy.




coo

Director Kamal Rubbishes Sexual Harassment Allegations Against Him, Calls It A Cooked Up Story

Of lately, Kerala was shocked after the news of the ace filmmaker and Kerala State Chalchithra Academy Chairman Kamal being accused of sexual harassment surfaced. The serious allegations were made by a young actress of Mollywood, who complained that he had




coo

Nivin Pauly, Aju Varghese, & Dhyan Sreenivasan Team Up Again: What's Cooking?

Nivin Pauly, Aju Varghese, and Dhyan Sreenivasan, the popular actors last joined hands for Love Action Drama, the superhit romantic comedy. Interestingly, the trio is now joining hands once again, to the much-excitement of the audiences. Aju Varghese revealed the exciting




coo

Mahabharat: After Cooler, Netizens Spot A Dead Man Coming Back To Life In A Scene!

Post the lockdown, Doordarshan re-aired mythological shows Ramayan and Mahabharat on popular demand. Ever since then, the shows are making a lot of noise. The viewers have been following the shows very closely. Recently, netizens spotted a cooler behind Bhishma Pitamah




coo

Mother's Day 2020: From Mira Rajput To Kareena Kapoor, Meet B-Towns' Coolest Moms

Being a mother is more than a full-time job and some of the B-town celebrities are doing it all while winning the world with their work and charm. From being the centre of attention on social media to paparazzi following them,




coo

Mother's Day 2020: From Mira Rajput To Kareena Kapoor, Meet B-Towns' Coolest Moms

Being a mother is more than a full-time job and some of the B-town celebrities are doing it all while winning the world with their work and charm. From being the centre of attention on social media to paparazzi following them,




coo

Hero MotoCorp To Enter EV Segment: Electric Maestro Scooter Spotted Ahead Of Launch

The Hero Maestro Electric Proto concept electric scooter has been spotted ahead of its India launch. The eMaestro electric scooter will be the brand's first product offering to the EV segment in India.




coo

Vespa BS6 Scooter Range Launched in India: Prices Start At Rs 93,035

Vespa BS6 scooters have been launched in the Indian market. The BS6 scooters are now available at a starting price of Rs 93,035 ex-showroom (Delhi).




coo

Top Bike News Of The Week: Vespa BS6 Scooters Launch, Bajaj Discover & V BS6, eMaestro & More

Top two-wheeler news for this week includes a bunch of new Italian scooters introduced in the Indian market, while a major auto manufacturer plans to enter the electric two-wheeler segment in the country. Also, Bajaj and Royal Enfield have announced their future plans. Here are all the details:




coo

Giants renegotiate Cooper Rush’s deal

The Giants claimed Cooper Rush off waivers from their division rivals earlier this week. It makes sense given Rush's familiarity with new offensive coordinator Jason Garrett's offense. Rush can help teach it to starter Daniel Jones. Of course, the Giants don't expect Rush to play. Thus, they renegotiated Rush's deal, which was due to pay [more]




coo

Will cooperate with steps taken by PM, CM in this hour of shared challenge: SAD




coo

Punjab CM forms 13-member control room to coordinate wheat harvesting




coo

Chandigarh Police's trapper for uncooperative corona patients




coo

Panchkula: Cook at police dept tests positive




coo

Poly[(μ4-5,7-di­hydro-1H,3H-dithieno[3,4-b:3',4'-e]pyrazine-κ4N:N':S:S')tetra-μ3-iodido-tetra­copper]: a three-dimensional copper(I) coordination polymer

The reaction of ligand 5,7-di­hydro-1H,3H-dithieno[3,4-b:3',4'-e]pyrazine (L) with CuI lead to the formation of a three-dimensional coordination polymer, incorporating the well known [CuxIx]n staircase motif (x = 4). These polymer [Cu4I4]n chains are linked via the N and S atoms of the ligand to form the three-dimensional coordination polymer poly[(μ4-5,7-di­hydro-1H,3H-dithieno[3,4-b:3',4'-e]pyrazine-κ4N:N':S:S')tetra-μ3-iodido-tetra­copper], [Cu4I4(C8H8N2S2)]n (I). The asymmetric unit is composed of half a ligand mol­ecule, with the pyrazine ring located about a center of symmetry, and two independent copper(I) atoms and two independent I− ions forming the staircase motif via centers of inversion symmetry. The framework is consolidated by C—H⋯I hydrogen bonds.




coo

Poly[[μ4-3,4,8,10,11,13-hexa­hydro-1H,6H-bis­([1,4]di­thio­cino)[6,7-b:6',7'-e]pyrazine]di-μ-iodido-dicopper(I)]: a two-dimensional copper(I) coordination polymer

The reaction of ligand 3,4,8,10,11,13-hexa­hydro-1H,6H-bis­([1,4]di­thio­cino)[6,7-b:6',7'-e]pyrazine (L) with CuI led to the formation of a two-dimensional coordination polymer, incorporating a [Cu2I2] motif. These units are linked via the four S atoms of the ligand to form the title two-dimensional coordination poly­mer, poly[[μ4-3,4,8,10,11,13-hexa­hydro-1H,6H-bis­([1,4]di­thio­cino)[6,7-b:6',7'-e]pyrazine]di-μ-iodido-dicopper(I)], [Cu2I2(C12H16N2S4)]n, (I). The asymmetric unit is composed of a ligand mol­ecule, two copper(I) atoms and two I− ions. Both copper(I) atoms are fourfold S2I2 coordinate with almost regular trigonal-pyramidal environments. In the crystal, the layers, lying parallel to (102), are linked by C—H⋯I hydrogen bonds, forming a supra­molecular framework.




coo

A molybdenum tris­(di­thiol­ene) complex coordinates to three bound cobalt centers in three different ways

The synthesis and structural characterization of the mol­ecular compound (μ3-benzene-1,2-di­thiol­ato)hexa­carbonyl­bis­(μ3-1,1,1,4,4,4-hexafluorobut-2-ene-2,3-dithiolato)tricobaltmolybdenum, [Co3Mo(C4F6S2)2(C6H4S2)(CO)6] or Mo(tfd)2(bdt)(Co(CO)2)3 (tfd is 1,1,1,4,4,4-hexafluorobut-2-ene-2,3-dithiolate and bdt is benzene-1,2-di­thiol­ate), are reported. The structure of the mol­ecule contains the molybdenum tris­(di­thiol­ene) complex Mo(tfd)2(bdt) coordinated as a multidentate ligand to three cobalt dicarbonyl units. Each of the three cobalt centers is relatively close to molybdenum, with Co⋯Mo distances of 2.7224 (7), 2.8058 (7), and 2.6320 (6) Å. Additionally, each of the cobalt centers is bound via main-group donor atoms, but each one in a different way: the first cobalt atom is coordinated by two sulfur atoms from different di­thiol­enes (bdt and tfd). The second cobalt atom is coordinated by one sulfur from one tfd and two olefinic carbons from another tfd. The third cobalt is coordinated by one sulfur from bdt and two sulfurs from tfd. This is, to the best of our knowledge, the first structurally characterized example of a molybdenum (tris­)di­thiol­ene complex that coordinates to cobalt. The F atoms of two of the –CF3 groups were refined as disordered over two sets of sites with ratios of refined occupancies of 0.703 (7):0.297 (7) and 0.72 (2):0.28 (2).




coo

Palladium(II) complexes of a bridging amine bis­(phenolate) ligand featuring κ2 and κ3 coordination modes

Bidentate and tridentate coordination of a 2,4-di-tert-butyl-substituted bridging amine bis­(phenolate) ligand to a palladium(II) center are observed within the same crystal structure, namely di­chlorido­({6,6'-[(ethane-1,2-diylbis(methyl­aza­nedi­yl)]bis­(methyl­ene)}bis­(2,4-di-tert-butyl­phenol))palladium(II) chlorido­(2,4-di-tert-butyl-6-{[(2-{[(3,5-di-tert-butyl-2-hy­droxy­phen­yl)meth­yl](meth­yl)amino}­eth­yl)(meth­yl)amino]­meth­yl}phenolato)palladium(II) methanol 1.685-solvate 0.315-hydrate, [PdCl2(C34H56N2O2)][PdCl(C34H55N2O2)]·1.685CH3OH·0.315H2O. Both complexes exhibit a square-planar geometry, with unbound phenol moieties participating in inter­molecular hydrogen bonding with co-crystallized water and methanol. The presence of both κ2 and κ3 coordination modes arising from the same solution suggest a dynamic process in which phenol donors may coordinate or dissociate from the metal center, and offers insight into catalyst speciation throughout Pd-mediated processes. The unit cell contains di­chlorido­({6,6'-[(ethane-1,2-diylbis(methyl­aza­nedi­yl)]bis­(methyl­ene)}bis­(2,4-di-tert-butyl­phenol))palladium(II), {(L2)PdCl2}, and chlorido­(2,4-di-tert-butyl-6-{[(2-{[(3,5-di-tert-butyl-2-hy­droxy­phen­yl)meth­yl](methyl)amino}eth­yl)(meth­yl)amino]­meth­yl}phenolato)palladium(II), {(L2X)PdCl}, mol­ecules as well as fractional water and methanol solvent mol­ecules.




coo

Crystal structures of four dimeric manganese(II) bromide coordination complexes with various derivatives of pyridine N-oxide

Four manganese(II) bromide coordination complexes have been prepared with four pyridine N-oxides, viz. pyridine N-oxide (PNO), 2-methyl­pyridine N-oxide (2MePNO), 3-methyl­pyridine N-oxide (3MePNO), and 4-methyl­pyridine N-oxide (4MePNO). The compounds are bis­(μ-pyridine N-oxide)bis­[aqua­dibromido­(pyridine N-oxide)manganese(II)], [Mn2Br4(C5H5NO)4(H2O)2] (I), bis­(μ-2-methyl­pyridine N-oxide)bis­[di­aqua­dibromido­manganese(II)]–2-methyl­pyridine N-oxide (1/2), [Mn2Br4(C6H7NO)2(H2O)4]·2C6H7NO (II), bis­(μ-3-methyl­pyridine N-oxide)bis­[aqua­dibromido­(3-methyl­pyridine N-oxide)manganese(II)], [Mn2Br4(C6H7NO)4(H2O)2] (III), and bis­(μ-4-methyl­pyridine N-oxide)bis­[di­bromido­methanol(4-methyl­pyridine N-oxide)manganese(II)], [Mn2Br4(C6H7NO)4(CH3OH)2] (IV). All the compounds have one unique MnII atom and form a dimeric complex that contains two MnII atoms related by a crystallographic inversion center. Pseudo-octa­hedral six-coordinate manganese(II) centers are found in all four compounds. All four compounds form dimers of Mn atoms bridged by the oxygen atom of the PNO ligand. Compounds I, II and III exhibit a bound water of solvation, whereas compound IV contains a bound methanol mol­ecule of solvation. Compounds I, III and IV exhibit the same arrangement of mol­ecules around each manganese atom, ligated by two bromide ions, oxygen atoms of two PNO ligands and one solvent mol­ecule, whereas in compound II each manganese atom is ligated by two bromide ions, one O atom of a PNO ligand and two water mol­ecules with a second PNO mol­ecule inter­acting with the complex via hydrogen bonding through the bound water mol­ecules. All of the compounds form extended hydrogen-bonding networks, and compounds I, II, and IV exhibit offset π-stacking between PNO ligands of neighboring dimers.




coo

One-dimensional ladder gallium coordination polymer

A one-dimensional ladder-type coordination polymer, poly[[(μ2-hydroxido)(μ2-1H-pyrazole-3,5-di­carboxyl­ato)gallium(III)] monohydrate], [Ga(C5H2N2O4)(OH)(H2O)]n or [Ga(HPDC)(OH)(H2O)]n, I, isotypic with a V3+ coordination polymer previously reported by Chen et al. [J. Coord. Chem. (2008). 61, 3556–3567] was prepared from Ga3+ and pyrazole-3,5-di­carb­oxy­lic acid monohydrate (H3PDC·H2O). Compound I was isolated using three distinct experimental methods: hydro­thermal (HT), microwave-assisted (MWAS) and one-pot (OP) and the crystallite size should be fine-tuned according to the method employed. The coordination polymeric structure is based on a dimeric Ga3+ moiety comprising two μ2-bridging hydroxide groups, which are inter­connected by HPDC2− anionic organic linkers. The close packing of individual polymers is strongly directed by the supra­molecular inter­actions, namely several O—H⋯O and N—H⋯O hydrogen-bonding inter­actions.




coo

Crystal structure of a two-dimensional coordination polymer of formula [Zn(NDC)(DEF)] (H2NDC is naphthalene-2,6-di­carb­oxy­lic acid and DEF is N,N-di­ethyl­formamide)

A zinc metal–organic framework, namely poly[bis­(N,N-di­ethyl­formamide)(μ4-naphthalene-2,6-di­carboxyl­ato)(μ2-naphthalene-2,6-di­carboxyl­ato)dizinc(II)], [Zn(C12H6O4)(C15H11NO)]n, built from windmill-type secondary building units and forming zigzag shaped two-dimensional stacked layers, has been solvothermally synthesized from naphthalene-2,6-di­carb­oxy­lic acid and zinc(II) acetate as the metal source in N,N-di­ethyl­formamide containing small amounts of formic acid.




coo

Crystal structures of two coordination isomers of copper(II) 4-sulfo­benzoic acid hexa­hydrate and two mixed silver/potassium 4-sulfo­benzoic acid salts

A reaction of copper(II) carbonate and potassium 4-sulfo­benzoic acid in water acidified with hydro­chloric acid yielded two crystalline products. Tetra­aqua­bis­(4-carb­oxy­benzene­sulfonato)­copper(II) dihydrate, [Cu(O3SC6H4CO2H)2(H2O)4]·2H2O, (I), crystallizes in the triclinic space group Poverline{1} with the Cu2+ ions located on centers of inversion. Each copper ion is coordinated to four water mol­ecules in a square plane with two sulfonate O atoms in the apical positions of a Jahn–Teller-distorted octa­hedron. The carboxyl­ate group is protonated and not involved in coordination to the metal ions. The complexes pack so as to create a layered structure with alternating inorganic and organic domains. The packing is reinforced by several O—H⋯O hydrogen bonds involving coordinated and non-coordinated water mol­ecules, the carb­oxy­lic acid group and the sulfonate group. Hexa­aqua­copper(II) 4-carb­oxy­benzene­sulfonate, [Cu(H2O)6](O3SC6H4CO2H)2, (II), also crystallizes in the triclinic space group Poverline{1} with Jahn–Teller-distorted octa­hedral copper(II) aqua complexes on the centers of inversion. As in (I), the carboxyl­ate group on the anion is protonated and the structure consists of alternating layers of inorganic cations and organic anions linked by O—H⋯O hydrogen bonds. A reaction of silver nitrate and potassium 4-sulfo­benzoic acid in water also resulted in two distinct products that have been structurally characterized. An anhydrous silver potassium 4-carb­oxy­benzene­sulfonate salt, [Ag0.69K0.31](O3SC6H4CO2H), (III), crystallizes in the monoclinic space group C2/c. There are two independent metal sites, one fully occupied by silver ions and the other showing a 62% K+/38% Ag+ (fixed) ratio, refined in two slightly different positions. The coordination environments of the metal ions are composed primarily of sulfonate O atoms, with some participation by the non-protonated carboxyl­ate O atoms in the disordered site. As in the copper compounds, the cations and anions cleanly segregate into alternating layers. A hydrated mixed silver potassium 4-carb­oxy­benzene­sulfonate salt dihydrate, [Ag0.20K0.80](O3SC6H4CO2H)·2H2O, (IV), crystallizes in the monoclinic space group P21/c with the Ag+ and K+ ions sharing one unique metal site coordinated by two water mol­ecules and six sulfonate O atoms. The packing in (IV) follows the dominant motif of alternating inorganic and organic layers. The protonated carboxyl­ate groups do not inter­act with the cations directly, but do participate in hydrogen bonds with the coordinated water mol­ecules. (IV) is isostructural with pure potassium 4-sulfo­benzoic acid dihydrate.




coo

Crystal structure and Hirshfeld surface analysis of poly[tris­(μ4-benzene-1,4-di­carboxyl­ato)tetra­kis­(di­methyl­formamide)­trinickel(II)]: a two-dimensional coordination network

The crystal structure of the title compound, [Ni3(C8H4O4)3(C3H7NO)4], is a two-dimensional coordination network formed by trinuclear linear Ni3(tp)3(DMF)4 units (tp = terephthalate = benzene-1,4-di­carboxyl­ate and DMF = di­methyl­formamide) displaying a characteristic coordination mode of acetate groups in polynuclear metal–organic compounds. Individual trinuclear units are connected through tp anions in a triangular network that forms layers. One of the DMF ligands points outwards and provides inter­actions with equivalent planes above and below, leaving the second ligand in a structural void much larger than the DMF mol­ecule, which shows positional disorder. Parallel planes are connected mainly through weak C—H⋯O, H⋯H and H⋯C inter­actions between DMF mol­ecules, as shown by Hirshfeld surface analysis.




coo

Crystal structure of the coordination polymer catena-poly[[[(acetonitrile-κN)copper(I)]-μ3-1,3-dithiolane-κ3S:S:S'] hexafluoridophosphate]

The polymeric title compound, [Cu2(C2H3N)2(C3H6S2)2](PF6)2, represents an example of a one-dimensional coordination polymer resulting from the reaction of [Cu(MeCN)4][PF6] with 1,3-di­thiol­ane. The cationic one-dimensional ribbon consists of two copper(I) centers each ligated by one aceto­nitrile mol­ecule and inter­connected through two bridging 1,3-di­thiol­ane ligands. One S-donor site of each ligand is κ1-bound to Cu, whereas the second S atom acts as a four-electron donor, bridging two Cu atoms in a κ4-bonding mode. The positive charge of each copper cation is compensated for by a hexa­fluorido­phosphate counter-ion. In the crystal, the polymer chains are linked by a series of C—H⋯F hydrogen bonds, forming a supra­molecular framework. The crystal studied was refined as a two-component twin.




coo

Crystal structure and Hirshfeld surface analysis of a copper(II) complex with ethyl­enedi­amine and non-coordinated benzoate

In the title compound, di­aqua­bis­(ethyl­enedi­amine-κ2N,N')copper(II) bis­(2-nitro­benzoate), [Cu(C2H8N2)2(H2O)2](C7H4NO4)2, two di­aqua­bis­(ethyl­enedi­amine)­copper(II) cations and four nitro­benzoate anions are present in the asymmetric unit. All four anions are `whole-mol­ecule' disordered over two sets of sites. The major components have refined occupancies of 0.572 (13), 0.591 (9), 0.601 (9) and 0.794 (10). The CuII ions exhibit slightly distorted octa­hedral geometries. In the crystal, cations and anions are connected to each other via N—H⋯O and O—H⋯O hydrogen bonds, forming a two-dimensional network parallel to (200). The inter­molecular contacts in the crystal were further analysed using Hirshfeld surface analysis, which indicates that the most significant contacts are O⋯H/H⋯O (42.9%), followed by H⋯H (35.7%), C⋯H/H⋯C (14.2%), C⋯C (2.9%), C⋯O/O⋯C (2.2%), N⋯H/H⋯N (0.9%) and N⋯O/O⋯N (0.3%).




coo

The first coordination compound of deprotonated 2-bromo­nicotinic acid: crystal structure of a dinuclear paddle-wheel copper(II) complex

A copper(II) dimer with the deprotonated anion of 2-bromo­nicotinic acid (2-BrnicH), namely, tetrakis(μ-2-bromonicotinato-κ2O:O')bis[aquacopper(­II)](Cu—Cu), [Cu2(H2O)2(C6H3BrNO2)4] or [Cu2(H2O)2(2-Brnic)4], (1), was prepared by the reaction of copper(II) chloride dihydrate and 2-bromo­nicotinic acid in water. The copper(II) ion in 1 has a distorted square-pyramidal coordination environment, achieved by four carboxyl­ate O atoms in the basal plane and the water mol­ecule in the apical position. The pair of symmetry-related copper(II) ions are connected into a centrosymmetric paddle-wheel dinuclear cluster [Cu⋯Cu = 2.6470 (11) Å] via four O,O'-bridging 2-bromo­nicotinate ligands in the syn-syn coordination mode. In the extended structure of 1, the cluster mol­ecules are assembled into an infinite two-dimensional hydrogen-bonded network lying parallel to the (001) plane via strong O—H⋯O and O—H⋯N hydrogen bonds, leading to the formation of various hydrogen-bond ring motifs: dimeric R22(8) and R22(16) loops and a tetra­meric R44(16) loop. The Hirshfeld surface analysis was also performed in order to better illustrate the nature and abundance of the inter­molecular contacts in the structure of 1.




coo

Syntheses and crystal structures of the one-dimensional coordination polymers formed by [Ni(cyclam)]2+ cations and 1,3-bis­(3-carb­oxy­prop­yl)tetra­methyl­disiloxane anions in different degrees of deprotonation

The asymmetric units of the title compounds, namely, catena-poly[[(1,4,8,11-tetra­aza­cyclo­tetra­decane-κ4N1,N4,N8,N11)nickel(II)]-μ-1,3-bis­(3-carboxyl­ato­prop­yl)tetra­methyl­disiloxane-κ2O:O'], [Ni(C10H24O5Si2)(C12H24N4)]n (I), and catena-poly[[[(1,4,8,11-tetra­aza­cyclo­tetra­decane-κ4N1,N4,N8,N11)nickel(II)]-μ-4-({[(3-carb­oxy­prop­yl)di­methyl­sil­yl]­oxy}di­methyl­sil­yl)butano­ato-κ2O:O'] per­chlorate], {[Ni(C10H25O5Si2)(C12H24N4)]ClO4}n (II), consist of one (in I) or two crystallographically non-equivalent (in II) centrosymmetric macrocyclic cations and one centrosymmetric dianion (in I) or two centrosymmetric monoanions (in II). In each compound, the metal ion is coordinated by the four secondary N atoms of the macrocyclic ligand, which adopts the most energetically stable trans-III conformation, and the mutually trans O atoms of the carboxyl­ate in a slightly tetra­gonally distorted trans-NiN4O2 octa­hedral coordination geometry. The crystals of both types of compounds are composed of parallel polymeric chains of the macrocyclic cations linked by the anions of the acid running along the [101] and [110] directions in I and II, respectively. In I, each polymeric chain is linked to four neighbouring ones by hydrogen bonding between the NH groups of the macrocycle and the carboxyl­ate O atoms, thus forming a three-dimensional supra­molecular network. In II, each polymeric chain contacts with only two neighbours, forming hydrogen bonds between the partially protonated carb­oxy­lic groups of the bridging ligand. As a result, a lamellar structure is formed with the layers oriented parallel to the (1overline{1}1) plane.




coo

The first coordination compound of 6-fluoro­nicotinate: the crystal structure of a one-dimensional nickel(II) coordination polymer containing the mixed ligands 6-fluoro­nicotinate and 4,4'-bi­pyridine

A one-dimensional nickel(II) coordination polymer with the mixed ligands 6-fluoro­nicotinate (6-Fnic) and 4,4'-bi­pyridine (4,4'-bpy), namely, catena-poly[[di­aqua­bis­(6-fluoro­pyridine-3-carboxyl­ato-κO)nickel(II)]-μ-4,4'-bi­pyri­dine-κ2N:N'] trihydrate], {[Ni(6-Fnic)2(4,4'-bpy)(H2O)2]·3H2O}n, (1), was prepared by the reaction of nickel(II) sulfate hepta­hydrate, 6-fluoro­nicotinic acid (C6H4FNO2) and 4,4'-bi­pyridine (C10H8N2) in a mixture of water and ethanol. The nickel(II) ion in 1 is octa­hedrally coordinated by the O atoms of two water mol­ecules, two O atoms from O-monodentate 6-fluoro­nicotinate ligands and two N atoms from bridging 4,4'-bi­pyridine ligands, forming a trans isomer. The bridging 4,4'-bi­pyridine ligands connect symmetry-related nickel(II) ions into infinite one-dimensional polymeric chains running in the [1overline{1}0] direction. In the extended structure of 1, the polymeric chains and lattice water mol­ecules are connected into a three-dimensional hydrogen-bonded network via strong O—H⋯O and O—H⋯N hydrogen bonds, leading to the formation of distinct hydrogen-bond ring motifs: octa­meric R88(24) and hexa­meric R86(16) loops.




coo

Silver(I) nitrate two-dimensional coordination polymers of two new pyrazine­thio­phane ligands: 5,7-di­hydro-1H,3H-dithieno[3,4-b:3',4'-e]pyrazine and 3,4,8,10,11,13-hexa­hydro-1H,6H-bis­([1,4]di­thio­cino)[6,7-b:6',7'-e

The two new pyrazine­ophanes, 5,7-di­hydro-1H,3H-dithieno[3,4-b:3',4'-e]pyrazine, C8H8N2S2, L1, and 3,4,8,10,11,13-hexa­hydro-1H,6H-bis­([1,4]di­thio­cino)[6,7-b:6',7'-e]pyrazine, C12H16N2S4, L2, both crystallize with half a mol­ecule in the asymmetric unit; the whole mol­ecules are generated by inversion symmetry. The mol­ecule of L1, which is planar (r.m.s. deviation = 0.008 Å), consists of two sulfur atoms linked by a rigid tetra-2,3,5,6-methyl­ene­pyrazine unit, forming planar five-membered rings. The mol­ecule of L2 is step-shaped and consists of two S–CH2–CH2–S chains linked by the central rigid tetra-2,3,5,6-methyl­ene­pyrazine unit, forming eight-membered rings that have twist-boat-chair con­fig­urations. In the crystals of both compounds, there are no significant inter­molecular inter­actions present. The reaction of L1 with silver nitrate leads to the formation of a two-dimensional coordination polymer, poly[(μ-5,7-di­hydro-1H,3H-dithieno[3,4-b;3',4'-e]pyrazine-κ2S:S')(μ-nitrato-κ2O:O')silver(I)], [Ag(NO3)(C8H8N2S2)]n, (I), with the nitrato anion bridging two equivalent silver atoms. The central pyrazine ring is situated about an inversion center and the silver atom lies on a twofold rotation axis that bis­ects the nitrato anion. The silver atom has a fourfold AgO2S2 coordination sphere with a distorted shape. The reaction of L2 with silver nitrate also leads to the formation of a two-dimensional coordination polymer, poly[[μ33,4,8,10,11,13-hexa­hydro-1H,6H-bis­([1,4]di­thio­cino)[6,7-b;6',7'-e]pyrazine-κ3S:S':S''](nitrato-κO)silver(I)], [Ag(NO3)(C12H16N2S4)]n, (II), with the nitrate anion coordinating in a monodentate manner to the silver atom. The silver atom has a fourfold AgOS3 coordination sphere with a distorted shape. In the crystals of both complexes, the networks are linked by C—H⋯O hydrogen bonds, forming supra­molecular frameworks. There are additional C—H⋯S contacts present in the supra­molecular framework of II.