Assembly of 3D coordination polymers from 2D sheets by [2+2] cycloaddition reaction.

The synthesis of three 2D interdigitated Zn(II) coordination polymers (CPs), by using three monotopic ligands containing C=C bonds, is reported. Among these, two CPs with 4spy (4-styryl pyridine) and 2F-4spy (a 2'-fluoro derivative of 4spy) ligands showed quantitative formation of cyclobutane rings, thus demonstrating a unique synthetic procedure to synthesize metal-organic frameworks (MOFs) by using this photochemical reaction. Interestingly, these compounds can also be synthesized by mechanochemical grinding procedures by using Zn(OAc)2.

Thermally reversible single-crystal to single-crystal transformation of mononuclear to dinuclear Zn(II) complexes by [2+2] cycloaddition reaction.

Two Zn(II) complexes of trans-4-styrylpyridine ligands undergo [2+2] cycloaddition reaction forming Zn(II) complex dimers in a single-crystal to single-crystal (SCSC) manner which were thermally reversible. The dimers are presumed to be the stable intermediates in the formation of 1D coordination polymers upon prolonged exposure to UV light.

Influence of C-H···π interactions on the solid-state [2+2] cycloaddition reaction of a Ag(I) coordination complex in an inorganic co-crystal.

The C-H···π interaction plays a vital role in directing a single-crystal to single-crystal [2+2] cycloaddition reaction to form an intramolecular head-to-head photodimer compared to an intermolecular head-to-tail photoproduct of 4-styrylpyridine of a Ag(I) coordination complex in an inorganic co-crystal.

7-(4-Fluoro-benzyl-amino)-2-phenyl-1,2,4-triazolo[1,5-a][1,3,5]triazin-5-amine methanol disolvate.

The 1,2,4-triazolo[1,5-a][1,3,5]triazine system in the title compound, C(17)H(14)FN(7)·2CH(3)OH, is essentially planar, with an r.m.s.

Metal-organic frameworks containing a tetrapyridylcyclobutane ligand derived from isomerization reaction.

The rctt isomer of tetrapyridylcyclobutane prepared from the solid-state [2 + 2] cycloaddition reaction of [bpeH(2)] x 2 CF(3)CO(2) [bpe = 1,2-bis(4-pyridyl)ethene] undergoes isomerization reaction to the rtct isomer in 100% yield, and this tetrahedral tetrapyridyl ligand forms two metal-organic frameworks having ptt and pts topology.

One-step formation of cyclometallated Au(III) N,S-heterocyclic carbene: crystallographic analysis.

Gold(I) N,S-heterocyclic carbene AuBr(NSHC) (NSHC = N-allylbenzothiazolin-2-ylidene) (1) with an allyl pendant is oxidised by iodine to give [AuI2(NSHC)2]+[I3]- (2) and a cyclometallated byproduct AuBr2(-C6H4SCNCH2CHCH2Br-C,C) (3). The latter can be prepared directly from bromination of 1. Similar reaction with the crotyl (but-2-en-1-yl) derivative AuBr(NSHC) (NSHC = N-crotylbenzothiazolin-2-ylidene) (4) gives an oxidative addition product AuBr3(C6H4SCNCH2CHCHCH3) (5).

Substituent-dependent structures and catalysis of benzimidazole-tethered N-heterocyclic carbene complexes of Ag(I), Ni(II) and Pd(II).

Homoleptic cationic benzimidazole-imidazolin-2-ylidene N-heterocyclic carbene (NHC = L) complexes of Ni(II) and Pd(II) have been prepared directly from the ligand precursor in salt form [H.L]Cl and from the transmetallation route via Ag(I). The N-tether of the imidazolinylidene ring imposes a significant influence on the nuclearity of the intermediate Ag(I)-NHC complexes and the geometric isomer outcome of the d(8) products.

A new ligand for metal-organic framework and co-crystal synthesis: mechanochemical route to rctt-1,2,3,4-tetrakis-(4'-carboxyphenyl)-cyclobutane.

A novel method to access rctt-1,2,3,4-tetrakis-(4'-carboxyphenyl)-cyclobutane in quantitative yield from an environmentally benign route is presented. The cyclobutane derivative is demonstrated as a potential candidate to serve as an organic building block for making co-crystal and MOF.

Functionalized 1,2,3-triazoles as building blocks for photoluminescent POLOs (polymers of oligomers) of copper(I).

Two 3-D and one 2-D metal-organic frameworks [Cu(8)I(8)(L1)(4)](n) (1), [Cu(8)I(8)(L2)(4)](n) (2) and [Cu(4)I(4)(L3)(2)](n) ()3 were synthesized using three novel pyridine and pyrazole supported 1,2,3-triazoles, 1-(4-picolyl)-4-butyl-1H-1,2,3-triazole (L1), 1-(4-picolyl)-4-pentyl-1H-1,2,3-triazole (L2) and 1-(4-picolyl)-4-(3,5-dimethylpyrazolylmethyl)-1H-1,2,3-triazole (L3). In both complexes 1 and 2, there co-exist a 1-D Cu(I) oligomer and Cu(4) tetrahedron cluster in the 3-D polymeric structures. Complex 3 shows a 2-D (4, 4) net with the stair-step Cu(4)I(4) as node and L3 as a building block.

[Pt2(mu-SAz)(mu-S)]2+ (SAz = azolium thiolate) dication as an unusual source for quadruply bridging sulfide in [Ag2Pt2(mu-SAz)(mu4-S)]3+.

Functionalisation of the {Pt(2)(mu-S)(2)} core of [Pt(2)(mu-S)(2)(PPh(3))(4)] by imidazolium, benzimidazolium and thiazolium salts results in a series of cationic complexes with mixed-bridging ligands of azolium thiolate and sulfide. The complex [Pt(2)(mu-S)(mu-SCH(2)CH(2)C(3)H(3)N(2)CH(3))(PPh(3))(4)][PF(6)](2) reacts readily with Ag(OTf) (OTf = triflate) to give [Pt(2)(mu-SAg(2)CF(3)SO(4)H(2))(mu-SCH(2)CH(2)C(3)H(3)N(2)CH(3))(PPh(3))(4)][PF(6)](3). X-ray crystallographic analysis was carried out on [Pt(2)(mu-S)(mu-SCH(2)CH(2)C(3)H(3)N(2)CH(3))(PPh(3))(4)][PF(6)](2), [Pt(2)(mu-S)(mu-S(CH(2))(3)C(7)H(5)NS)(PPh(3))(4)][PF(6)](2), [Pt(2)(mu-S)(mu-SCH(2)CH(2)C(3)H(3)N(2)CH(3))(dppy)(4)][PF(6)](2), [Pt(2)(mu-S)(mu-SCH(2)CH(2)C(3)H(3)N(2)CH(3))(dppf)(4)][PF(6)](2), [Pt(2)(mu-SAg(2)CF(3)SO(4)H(2))(mu-SCH(2)CH(2)C(3)H(3)N(2)CH(3))(PPh(3))(4)][PF(6)](3) and [Pt(2)(mu-SCH(3))(mu-SCH(2)CH(2)C(3)H(3)N(2)CH(3))(PPh(3))(4)][PF(6)](3).

4-Amino-2,8-dimethyl-6H-pyrimido[1,2-a][1,3,5]triazin-6-one.

In the title compound, C(8)H(9)N(5)O, the mean planes through the pyrimidine and triazine rings form a dihedral angle of 2.83 (16)°. The amino group adopts a trigonal-planar configuration and forms an intra-molecular resonance-assisted N-H⋯O=C hydrogen bond with the carbonyl group.

A monoclinic polymorph of N-eth-oxy-carbonyl-N'-(3-phenyl-1H-1,2,4-triazol-5-yl)thio-urea.

The title compound, C(12)H(13)N(5)O(2)S {systematic name: ethyl N-[N-(3-phenyl-1H-1,2,4-triazol-5-yl)carbamothio-yl]carbamate}, is a monoclinic polymorph (space group P2(1)/c) which crystallizes with three similar independent mol-ecules in the asymmetric unit. The triazole ring makes dihedral angles of 6.6 (2), 8.

8-Methyl-2-[4-(trifluoro-meth-yl)phen-yl]-8H-pyrazolo-[4,3-e][1,2,4]triazolo[1,5-c]pyrimidin-5-amine methanol disolvate.

In the title compound, C(14)H(10)F(3)N(7)·2CH(4)O, the heterocyclic ring system is essentially planar (r.m.s.

N-Carbethoxy-N'-[3-(4-methylphenyl)-1H-1,2,4-triazol-5-yl]thiourea.

THE TITLE COMPOUND, [SYSTEMATIC NAME: ethyl ({[3-(4-methylphenyl)-1H-1,2,4-triazol-5-yl]amino}carbonothioyl)carbamate], C(13)H(16)N(5)O(2)S, exists in the 3-aryl-5-thio-ureido-1H-1,2,4-triazole tautomeric form. The mol-ecular structure is stabilized by intra-molecular hydrogen bonding (N-H⋯S=C between the endocyclic N-bound H atom and the thio-ureido S atom, and N-H⋯O=C within the ethoxy-carbonyl-thio-urea unit), both arranged in an S(6) graph-set motif. The mean planes of the phenyl and 1,2,4-triazole rings make a dihedral angle of 6.

N-Carbethoxy-N'-(3-phenyl-1H-1,2,4-triazol-5-yl)thiourea.

The title compound {systematic name: ethyl N-[N-(3-phenyl-1H-1,2,4-triazol-5-yl)carbamothio-yl]carbamate}, C(12)H(13)N(5)O(2)S, exists in the 3-phenyl-5-thio-ureido-1H-1,2,4-triazole tautomeric form stabilized by intra-molecular hydrogen bonding between the endocyclic NH H atom and the thio-ureido S atom. The mol-ecular structure is also stabilized by intra-molecular N-H⋯O=C hydrogen bonds arranged in an S(6) graph-set motif within the carbethoxy-thio-urea moiety. The mean planes of the phenyl and 1,2,4-triazole rings make a dihedral angle of 7.

4-Carbethoxy-1-[4-(N,N-dimethylamino)benzoyl]thiosemicarbazide.

The mol-ecular structure of the title compound, C(13)H(18)N(4)O(3)S, (systematic name: ethyl N-{2-[4-(dimethyl-amino)benzo-yl]hydrazinethio-carbon-yl}carbamate) is stabilized by intra-molecular N-H⋯O=C hydrogen bonding arranged in an S(6) graph-set motif. In the crystal, inversion dimers connected via inter-molecular N-H⋯S=C hydrogen bonds [R(2) (2)(8) graph-set motif] form sheets parallel to the (21) plane. Dimers are also formed by the mol-ecules via weak inter-molecular N-H⋯S=C hydrogen bonds [R(2) (2)(10) graph-set motif] connecting the sheets.

N'-Acetyl-5-amino-1-methyl-1H-pyrazole-4-carbohydrazonamide dihydrate.

In the title compound, C(7)H(12)N(6)O·2H(2)O, the Z configuration of the hydrazone fragment is stabilized by an intra-molecular N-H⋯N hydrogen bond involving one of the amino groups. In the crystal structure, the hydrazonamide mol-ecules are connected via inter-molecular N-H⋯O=C hydrogen bonds, forming C(7) chains running along [010]. The chains form sheets parallel to the (01).

2-Phenyl-7-(4-pyridyl-methyl-amino)-1,2,4-triazolo[1,5-a][1,3,5]triazin-5(4H)-one.

In the title compound, C(16)H(13)N(7)O, the 1,2,4-triazolo[1,5-a][1,3,5]triazine heterocyclic system is essentially planar (r.m.s.

4,4-Dimethyl-3,4-dihydro-pyrido[2',3':3,4]pyrazolo-[1,5-a][1,3,5]triazin-2-amine ethanol monosolvate.

In the title compound, C(10)H(12)N(6)·C(2)H(5)OH, the planarity of the heterocyclic system is slightly distorted at the triazine ring (r.m.s.

Unexpected coordination difference in geometric-isomerism between N,S- and N,N-heterocyclic carbenes in cyclometallated platinum(ii).

The reaction of [Pt(II)(2-phenylpyridine)(acac)] and benzothiazolium bromide yields the N,S-heterocyclic carbene ligand trans to pyridyl while, surprisingly, a very similar N,N-heterocyclic carbene coordinates predominantly trans to the cyclometallated carbon.

One-pot oxidation and protonation of a bridging sulfide and rare crystallographic evidence of a coordinated [SO] complex in [Pt2(micro-S2O2H)(PPh3)4]+.

One-pot oxidation and protonation of the sulfide bridging complex [Pt(2)(micro-S)(2)(PPh(3))(4)] can be promoted by lanthanide or scandium compounds, leading to the isolation of [Pt(2)(micro-S(2)O(2)H)(PPh(3))(4)](+); crystallographic elucidation confirmed sulfide mono-oxygenation without S-S bonding to give formally [SO](2-) in the form of an [SOHOS](3-) overhead bridge.

Structures of copper complexes of the hybrid [SNS] ligand of bis(2-(benzylthio)ethyl)amine and facile catalytic formation of 1-benzyl-4-phenyl-1H-1,2,3-triazole through click reaction.

A hybrid ligand, bis(2-(benzylthio)ethyl)amine (SNS), with an amine and two thioether donors reacts with Cu(II) to give mononuclear [CuCl(2)(SNS)] (1), [CuBr(2)(SNS)] (2), [Cu(OTf)(2)(SNS)(OH(2))] (3), and an one-dimensional Cu(I) coordination polymer [Cu(2)I(2)(SNS)](n) (4). All complexes have been characterized by single-crystal X-ray diffraction analysis, and 1-3 were studied by EPR analysis at room temperature. Complexes 1 and 2 are penta-coordinated with a distorted square pyramidal metal supported by a tridentate SNS ligand on the basal plane.

4-Hydrazino-1-methyl-pyrazolo[3,4-d]pyrimidine.

The title compound, C(6)H(8)N(6), crystallizes as an N-H⋯N hydrogen-bond-linked dimer of two almost identical mol-ecules in the asymmetric unit. Both of the mol-ecules are almost planar (rms deviations of 0.0186 and 0.