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The three-dimensional (3D) coordination polymers [Cd(tpmd)(NCX)2]n [X = O (1), S (2), and BH3 (3); tpmd = N,N,N',N'-tetrakis(pyridin-4-yl)methanediamine] have been determined to display their network structures through coordinated anionic ligands. Polymers 1 and 2 show nonporous structures, whereas polymer 3 shows a porous coordination framework. On the basis of the Cd(II) network structures, the 3D coordination polymer [Zn(tpmd)(NCBH3)2]n·nMeOH (4) was self-assembled. In the cases of polymers 1 and 2, pseudohalide ions acted to form nonporous network structures; however, in polymers 3 and 4, NCBH3- helps to construct porous network structures. Polymers 1-4 show strong ultraviolet luminescence emissions, depending on the pseudohalide ions present, compared to the tpmd ligands. Interestingly, coordination polymers 3 and 4 that possess NCBH3- ions exhibit high porosities and gas sorption properties. The polymers appeared to absorb N2, H2, CO2, and CH4. In the case of polymer 4, the structure is almost identical with that of polymer 3, except for the Cd(II) ion. However, polymer 4 has a larger void volume and higher gas absorption ability for N2 gas than polymer 3. For the sorption of gases, polymers 3 and 4 showed similar behaviors.

Dyes are considered as harmful water pollutants because of their high water solubility, wide uses and toxicity. A highly mesoporous metal-organic framework PCN-222(Fe), together with commercial activated carbon (AC), was applied for the removal of both cationic (brilliant green (BG), crystal violet (CV), and methylene blue (MB)) and anionic (acid red 1 (AR 1), acid blue 80 (AB 80) and methyl orange (MO)) dyes from water through adsorption. The adsorptive performances of PCN-222(Fe) are much higher than AC for big dyes (BG, CV, AR 1, and AB 80). On the contrary, PCN-222(Fe) and AC show not very much different performances for the adsorption of small dyes (MB and MO). The maximum adsorption capacity of PCN-222(Fe) for BG, CV, AR 1, and AB 80 was higher than that of any reported adsorbent so far. The remarkably high adsorption capacity of PCN-222(Fe) for BG (854 mg·g−1), CV (812 mg·g−1), AR 1 (417 mg·g−1) and AB 80 (371 mg·g−1) could be explained by suitable pore size of PCN-222(Fe) together with electrostatic and π-π interactions. Moreover, PCN-222(Fe) could be successfully regenerated and reused for several cycles without any severe decrease in adsorption performance. Therefore, PCN-222(Fe) is suggested as an effective adsorbent for the dyes (especially with big size) removal from water.

A facile synthetic approach has been adopted towards the synthesis of (2R,3R)-N2,N3-bis((S)-1-phenylethyl)butane-2,3-diamine via demetalation of its dichloro Zn(II) complex, which itself was separated from a mixture of diastereomeric Zn(II) complexes by fractional crystallization. The synthesized chiral 1,2-diamine ligand was evaluated as a chiral auxiliary for the Cu(II)-catalysed asymmetric Henry reaction of 3-phenylpropanal and nitromethane, yielding (S)-1-nitro-4-phenylbutan-2-ol in excellent yields (up to 99%) and enantioselectivities (up to 97%). A facile synthetic approach towards (2R,3R)-N2,N3-bis((S)-1-phenylethyl)butane-2,3-diamine (2b) via fractional crystallization and demetalation of its Zn(II) complex has been adopted. 2b served as a highly enantioselective pro-ligand with Cu(OAc)2 for asymmetric Henry reaction of 3-phenylpropanal and nitromethane in the presence of base with 97% > ee and 99% yield.

A series of Cu(II) complexes, [LnCuCl2]2 (Ln = (S)-N-((1H-pyrazol-1-yl)methyl)-1-phenylethanamine (L1), (S)-N-((3,5-dimethyl-1H-pyrazol-1-yl)methyl)-1-phenylethanamine (L2) and (S)-1-phenyl-N-((pyridin-2-yl)methyl)ethanamine (L3)) were synthesised and characterised. X-ray diffraction analysis revealed that the molecular structures of these distorted square planar Cu(II) complexes were dimeric with two asymmetric units crystallised in the (SC, SN) and (SC, RN) configurations. These are rare examples of dimeric Cu(II) complexes. The alkoxide derivatives, generated in situ, catalysed the ring-opening polymerisation of rac-lactide in a controlled fashion and displayed high activities (2 or 3 min for complete conversion). Heterotactic-enriched polylactide (with Pr up to 0.86) was formed using these initiators at room temperature in CH2Cl2.

A novel chiral resolution method for racemic 1-(pyridin-2-yl)ethylamine (PEA) was developed in this study. Sequential conversion of 1-(pyridin-2-yl)ethylamine to 1-(pyridin-2-yl)-N-((4R)-1,7,7-trimethylbicyclo[2.2.1]heptan-2-ylidene)ethylamine (PIC) and to dichloro{(E)-1-(pyridin-2-yl)-N-(1,7,7-trimethylbicyclo[2.2.1]heptan-2-ylidene)ethylamine}zinc (PIC-Zn) allowed for the spontaneous separation of dichloro{(1R,E)-1-(pyridin-2-yl)-N-(1,7,7-trimethylbicyclo[2.2.1]heptan-2-ylidene)ethylamine}zinc (RE-PIC-Zn) and dichloro{(1S,E)-1-(pyridin-2-yl)-N-(1,7,7-trimethylbicyclo[2.2.1]heptan-2-ylidene)ethylamine}zinc (SE-PIC-Zn) by fractional crystallization. The overall yields of both (S)- and (R)-PEA were 24.8% with estimated ee values of 98 and 99%, respectively. The preferred formation of diastereopure crystals over that of diastereomeric mixture crystals was interrogated by comparing the cohesive energies (Ecoh) of the respective crystals, as obtained via DFT calculations under periodic boundary conditions with a plane wave basis set based on the experimentally determined X-ray crystallographic structure. The Ecoh values of diastereopure SE-PIC-Zn and RE-PIC-Zn were −45.8 and −44.4 kcal mol−1, respectively. The Ecoh values of the diastereomeric mixture crystal (RE-PIC-Zn·SE-PIC-Zn·2CHCl3) and its virtual counterpart lacking CHCl3 (RE-PIC-Zn·SE-PIC-Zn) were −56.0 and −37.2 kcal mol−1, respectively. These data provided the background underlying the spontaneous segregation of the diastereopure crystals where the energy preference for forming diastereopure crystals over their corresponding diastereomeric mixture crystals is ca. 8 kcal mol−1.

A series of Zn(II) and Cu(II) complexes based on (chiral substituent)(diethyl)-ethanediamine derivatives, [LnMCl2] (where Ln = [(R)-N1,N1-diethyl-N2-(1-phenylethyl)ethane-1,2-diamine] (LA), [(R)-N1-(1-cyclohexylethyl)-N2,N2-diethylethane-1,2-diamine] (LB) and [N1,N1-diethyl-N2-(((1R)-6,6-dimethylbicyclo[3.1.1]hept-2-en-2-yl)methyl)ethane-1,2-diamine] (LC)) were synthesised and characterised by X-ray crystallography. The isopropoxide derivatives, [LnM(OiPr)2] generated in situ, effectively polymerised rac-lactide (rac-LA) and yielded heterotactic polylactide (PLA). The Cu(II) initiators exhibited better catalytic activities and mediated stereoselective ring-opening polymerisation (ROP) of rac-LA in a living manner to furnish PLA with higher heterotacticity compared with their Zn(II) analogous. The ROP activity of the current system largely relies on steric hindrance imposed by the substituents attached to the amine moiety of the (diethyl)-ethanediamine backbone.

A series of Zn(II) complexes bearing camphor-based ethyleneamine derivatives, [LnZnCl2] (Ln = [(E)-N1-ethyl-N2-(1,7,7-trimethylbicyclo[2.2.1]heptan-2-ylidene)ethane-1,2-diamine] (L1), [(E)-N1,N1-diethyl-N2-(1,7,7-trimethylbicyclo[2.2.1]heptan-2-ylidene)ethane-1,2-diamine] (L2), and [(E)-N-(1,7,7-trimethylbicyclo[2.2.1]heptan-2-ylidene)-2-(pyrrolidin-1-yl)ethanamine] (L3)), have been synthesised and characterised by X-ray crystallography. The isopropoxide derivatives [LnZn(OiPr)2] and [LnZnCl(OiPr)] (Ln = L1 − L3), generated in situ, effectively polymerised rac-lactide (rac-LA) to yield poly(lactide) (PLA) with high number-average molecular weights (Mn) and narrow polydispersity indices. Zn(II) initiators with less steric bulk at the amine moiety exhibited better catalytic activities; thus, the ring-opening polymerisation (ROP) activity of the catalytic system depended largely on the steric hindrance imposed by the substituents attached to the amine moiety of the ligand. All of the complexes mediated stereoselective ROP of rac-LA in a living manner to yield PLA with high heterotacticity (Pr up to 0.81).

Palladium(II) complexes, LnPdCl2 (Ln = LA–LI), with N,N′-bidentate imine ligands derived from picolinaldehyde and substituted anilines have been synthesized and structurally characterized. Molecular structures revealed a distorted square plane geometry around Pd(II) centre in LnPdCl2 (Ln = LA–LC) obtained via coordination with pyridine and imine nitrogens and two chloro ligands. Pd(II) complexes LnPdCl2 (Ln = LA–LI) initiate polymerisation of methylmethacrylate (MMA) in the presence of modified methylaluminoxane (MMAO). The complex LIPdCl2 (of which the ligand was N-furfuryl substituted) showed the highest catalytic activity for the polymerisation of MMA with an activity of 7.08 × 104 g PMMA/mol·Pd·h at 60 °C. All the complexes yielded syndio-rich poly(methyl methacrylate) (PMMA) ([rr] = 0.70). Notably, the substituents on the imine moiety of the iminopyridine fragments affects the activities towards MMA polymerization, whereas the stereoselectivities remained unchanged.

A series of Cu(II) complexes supported by methylthiophenyl- and methylfuryl-based (R,R)-1,2-diaminocyclohexane frameworks were synthesised. The synthesised complexes were characterised using infrared spectroscopy, elemental analysis, and single-crystal X-ray diffraction studies. The isopropoxide derivatives of the complexes were employed in the ring-opening polymerisation (ROP) of rac-lactide (rac-LA), yielding polylactides with high number-averaged molecular weight. The catalytic species in this study effectively mediated the stereoselective ROP of rac-LA in a physiological manner (Pr up to 0.92 at room temperature), with ROP activity being mainly dependent on steric hindrance and geometric constraints imposed by methyl substituents attached to the methylthiophenyl and methylfuryl ligands.

Two Fe(II)-based coordination polymers [Fe(tpmd)2(NCS)2]·5.5H2O (1) and [Fe(tpmd)2(NCSe)2]·7H2O (2) with the framework of square-grid type have been assembled from FeSO4·7H2O, N,N,N′,N′-tetrakis(pyridin-4-yl)methanediamine (tpmd), and KNCS/KNCSe in methanol and characterized. By utilizing two pyridine groups of a tpmd ligand, 1 and 2 are formed in two-dimensional layered structures through coordination of octahedral iron(II) ions with the tpmd to NCS−/NCSe− ligands in which they have a supramolecular isomorphous conformation. 1 shows a paramagnetic behavior between 2 and 300 K, while 2 exhibits two-step spin crossover (ca. 145 and 50 K) in the temperature range due to the coordination of NCSe− ligands. At 300 K 2 is fully high-spin state. However, at 100 K 2 becomes ca. 50% high spin and 50% low spin iron(II) ions, which is verified by magnetic moments. In the structural analysis of 2 at 100 K, two different layers are observed with different bond distances around iron(II) ions in which the layers are stacked alternately.

A series of Cu(II) complexes containing C1-symmetric thiophene derivatives of (1R,2R)-N1-(naphthalen-2-ylmethyl)cyclohexane-1,2-diamine, namely L1, L2 and L3 were synthesized and characterized. These complexes had distorted square-planar geometries around the Cu(II) center. High yield (99%) and excellent enantioselectivity (>99%) for (S)‐1‐nitro‐4‐phenylbutan‐2‐ol from the reaction of 3‐phenylpropanal and nitromethane was obtained using [L1Cu(OAc)2] or [L3Cu(OAc)2] with 10 mol% of diisopropylethylamine (DIPEA) within 24 h. The catalytic systems also demonstrated good activity and moderate to high enantioselectivity for aliphatic aldehydes.

We have synthesised the novel Cu(II) and Zn(II) complexes (CDM)CuCl2 and (CDM)ZnCl2, where CDM is (E)-N1,N1-dimethyl-N2-(1,7,7-trimethylbicyclo[2.2.1]heptan-2-ylidene)ethane-1,2-diamine. X-ray diffraction analysis revealed that the geometry around the Zn(II) centre can be best described as a distorted tetrahedron. In the Cu(II) complex, the bulk of camphor ligand suppresses the square planar geometry; the complex thus has a highly distorted square planar and distorted tetrahedral geometry. Alkoxy derivatives generated in situ proved to be highly efficient catalysts for the ring-opening polymerisation (ROP) of rac-lactide (rac-LA), yielding polylactide (PLA) with narrow polydispersity indexes (PDIs). (CDM)Cu(OCHMe2)2 exhibited a high activity for stereoselective ROP of rac-LA, with complete conversion within 2 min, producing heterotactic-enriched PLA (Pr = 0.85).

The reaction between [CuCl2·2H2O] and N,N′-bidentate N-(pyridin-2-ylmethyl)amines (Ln = LA–LE) in methanol yielded new Cu(II) complexes; namely mononuclear [LACuCl2] and dinuclear [LnCu(μ-Cl)Cl]2 (Ln = LB–LE) complexes, respectively. Monomeric [LACuCl2] showed a distorted square planar geometry around copper metal based on X-ray crystallography. The dimeric [LnCu(μ-Cl)Cl]2 (Ln = LB–LE) had a chloro-bridged 5-coordinated and a distorted square pyramidal geometry around the Cu(II) center. The range of Cu⋯Cu′ distance was 3.3238(6)–3.593(2) A in [LnCu(μ-Cl)Cl]2 (Ln = LB–LE). The Cu(II)-alkoxy derivatives, generated in situ, of these synthesized Cu(II) complexes have shown moderate activity towards the polymerization of rac-lactide (rac-LA) and yielded hetero-enriched PLA. The steric hindrance and electronic effects has a great influence on the catalytic activity and stereoselectivity of initiators.

Novel Zn(II) complexes, (N1E,N2E)-N1,N2-bis(1,7,7-trimethylbicyclo [2.2.1]heptan-2-ylidene)butane-1,2-diamine (BCE) ZnCl2 and (N1E,N3E)-2,2-dimethyl-N1,N3-bis(1,7,7-trimethylbicyclo [2.2.1]heptan-2-ylidene)pentane-1,3-diamine (BCP) ZnCl2, were synthesised. X-ray diffraction analysis revealed that the geometry around the Zn(II) centre is distorted tetrahedral. The alkoxy derivatives, generated in situ, were highly efficient catalysts for ring-opening polymerisation (ROP) of rac-lactide (rac-LA), yielding polylactide (PLA) with good number-average molecular weights and narrow polydispersity indices. (BCP)Zn(OCHMe2)2 exhibited activity for stereoselective ROP of rac-LA, and complete conversion occurred within 8 min to attain heterotactic PLA (Pr = 0.78).

Dinuclear FeIII and NiII complexes, [(phenO)Fe(N3)]2(NO3)2 (1) and [(phenOH)Ni(N3)2]2 (2), were prepared by treating Fe(NO3)3⋅9 H2O and Ni(NO3)2⋅6 H2O in methanol, respectively, with phenOH (=N-(2-pyridylmethyl)-N′-(2-hydroxyethyl)ethylenediamine) and NaN3; both 1 and 2 were characterized by elemental analysis, IR spectroscopy, X-ray diffraction, and magnetic susceptibility measurements. Two ethoxo-bridged FeIII and two azido-bridged NiII were observed in 1 and 2, respectively; corresponding antiferromagnetic interaction via the bridged ethoxo groups and strong ferromagnetic coupling via the bridged end-on azido ligands within the dimeric unit were observed. Complex 1 did not exhibit any catalytic activity, while 2 exhibited excellent catalytic activities for the epoxidation of aliphatic, aromatic, and terminal olefins.

SSZ-39 and mordenite zeolites were obtained from the conversion of zeolite Y in the presence of the same reaction precursors (organic templates, NaOH, water, etc.) under a wide range of reaction conditions. The applied templates were N,N-dialkyl-2,6-dimethyl-piperidinium-OH and -I (alkyl: ethyl or methyl). Curiously, SSZ-39 and mordenite were obtained from hydroxides and iodides, respectively, showing firstly the importance of the anion in the selective crystallization of zeolites. Reactions were also performed at the same set of pH values (achieved by adding small amounts of NaOH to the iodide-based precursors) to investigate the effect of basicity; the results did not vary appreciably with the pH of the synthesis precursors. Based on the phase conversion (MOR – > AEI or ANA with increasing reaction time and pH), the selective formation of SSZ-39 and mordenite from hydroxides and iodides, respectively, could be explained in terms of zeolite-promoting and -preventing anions (hydroxide and iodide, respectively). The phase conversion of zeolites could be explained on the basis of the maximum pore size of zeolites, rather than the framework densities. The obtained zeolites (SSZ-39 and mordenite), in their protonated forms, were employed in ethanol dehydration and direct ethylene-to-propylene conversion, and the results showed that the two zeolites have potential application in acid catalysis. In particular, the SSZ-39 with an AEI structure can be applied in the direct production of propylene from ethylene or ethanol.

The novel Cu(II) complexes Cu(L1)Cl2, Cu(L2)Cl2, and Cu(L3)Cl2, where L1 is N,N′-bis(benzyl)dimethyl-(R,R)-1,2-diaminocyclohexane, L2 is N,N’-bis(o-chlorobenzyl)dimethyl-(R,R)-1,2-diaminocyclohexane, and L3 is N,N′-bis(p-chlorobenzyl)dimethyl-(R,R)-1,2-diaminocyclohexane, were synthesised and structurally characterised using X-ray diffraction. The structures were mononuclear with Cu(II) atoms in distorted square planar geometries. The alkoxy derivatives of the dichloro Cu(II) rapidly polymerised rac-lactide (rac-LA) (

Enantiopure N,N-diamine has been obtained in an economical manner via demetalation of its corresponding dichloro Zn(II) complex, which is separated by fractional crystallization of two diastereomeric Zn(II) complexes. Polymerization of rac-lactide (rac-LA) initiated by diisopropoxide derivative proceeds rapidly at room temperature in a living fashion to yield heterotactic polylactide (PLA) with Pr = 0.90.

Two novel dichloro Cu(II) complexes of ( R , R )- N 1 , N 2 -bis((5-methylthiophen-2-yl)methyl)cyclohexane-1,2-diamine (MTCHD) and ( R , R )- N 1 , N 2 -bis((5-methylfuran-2-yl)methyl)cyclohexane-1,2-diamine (MFCHD) ligands have been synthesised and structurally characterised using X-ray diffraction. The geometry around the Cu(II) centres was distorted square planner. A strong Cu…O furanyl interaction exists in Cu(MFCHD)Cl 2 that leads to the disappearance of original C 2 -symmetry of the ligand, resulting in selective R , S- coordination of N atoms in (1 R ,2 R )-1,2-diaminocyclohexane. Catalytic activities of dichloro and diacetato Cu(II) complexes with 3 mol% of i Pr 2 NEt were assessed in asymmetric Henry reactions that resulted in moderate to high yields with an enantiomeric excess up to 92%, without air/moisture exclusion.

Reaction of copper(II) chloride dihydrate in methanol with deprotonated 3,5-diisopropylpyrazole-1-methanol (dippmOH) led to the tetranuclear copper(II) complex [(dippmO)CuCl]4 (1). The crystal structure of 1 indicates that two copper(II) ions connect via the oxygen atoms of dippmO− ligands each other in which two dimeric units are formed. Furthermore, one of the coordinated oxygen atoms in a dimer is bonded to an adjacent copper(II) ion positioned other dimer, which gives rise to a stepped tetranuclear structure. 1 shows strong antiferromagnetic interactions through the oxo groups within the dimeric units (J1 = − 239 cm− 1) and weak antiferromagnetic couplings between the dimers (J2 = − 15 cm− 1).

Two novel chiral zinc(II) complexes containing naphthalene moieties, namely [Zn(CMN)Cl2] (1) and [Zn(CBN)Cl2] (2), were obtained through the reaction of zinc(II) chloride with, respectively, (1R,2R)-N1-(naphthalen-2-ylmethyl)cyclohexane-1,2-diamine (CMN) and (1R,2R)-N1,N2-bis(naphthalen-2-ylmethyl)cyclohexane-1,2-diamine (CBN) in ethanol. The ligands CMN and CBN were characterized via infrared, nuclear magnetic resonance and absorption spectroscopic analyses. As regards to the two complexes, a comprehensive single crystal X-ray diffraction investigation showed that in both cases the zinc(II) ion is surrounded by two N atoms of CMN/CBN and two chloro groups, and has a distorted tetrahedral structure, though 2 also contains an additional naphthalene group. The photo-physical properties of 1 and 2 were examined based on their electronic absorption and photoluminescence spectra. Both complexes exhibited ultraviolet emissions (both at 335 nm in CHCl3; 336 and 385 nm for 1 and 337 nm for 2 in their solid states) under 278–298 nm excitation.

Chiral coordination polymers [Ni(L R,R )Ag(CN)2](ClO4)·CH3CN (3) and [Ni(L S,S )Ag(CN)2](ClO4)·CH3CN (4) were prepared by the reaction of K[Ag(CN)2] with [Ni(L R,R )](ClO4)2 (1) and [Ni(L S,S )](ClO4)2 (2), respectively (L R,R/S,S = 1,8-di((R/S)-α-methylbenzyl)-1,3,6,8,10,13-hexaazacyclotetradecane). The polymers were characterized by elemental analysis, spectroscopy, magnetic measurement and single crystal X-ray diffraction. In 3, the nickel(II) macrocyclic complexes link two Ag(CN) 2 − ions in axial position and each Ag(CN) 2 − ion binds two adjacent nickel(II) ions to form a 1-D chain structure. The structure of 4 is nearly same to that of 3, except for chirality. 3 and 4 exhibit very weak antiferromagnetic couplings through the bridged Ag(CN) 2 − ions within the 1-D chains (g = 2.20 and J/k B = −0.55 K for 3 and 4). The circular dichroism spectra of 3 and 4 show an enantiomeric pattern and have bisignate Cotton effects.

Two dichlorozinc complexes, (CIP)ZnCl2 and (CIPMe)ZnCl2 where CIP is (E)-1-(pyridin-2-yl)-N-(1,7,7-trimethylbicyclo[2.2.1]heptan-2-ylidene)methanamine and CIPMe is (E)-1-(6-methylpyridin-2-yl)-N-(1,7,7-trimethylbicyclo[2.2.1]heptan-2-ylidene)methanamine, were synthesised and characterised using X-ray diffraction. The coordination geometry around the four-coordinated zinc centres in these mononuclear complexes could be best described as distorted tetrahedral. Diisopropoxide derivatives of these complexes, generated in situ, efficiently initiated the ring-opening polymerisation (ROP) of rac-lactide (rac-LA). These metal initiators showed a preference for heterotactic polylactide (PLA), with a Pr value of 0.80 at −25 °C.

Two isomers of a new tetraaza macrotricycle 2,2,4,9,9,11-hexaazamethyl-1,5,8,12-tetraazatricyclo[10.2.2]octadecane (L) containing additional N-CH2CH2-N linkages, C-meso-L and C-racemic-L, have been prepared by the reaction of 1-bromo-2-chloroethane with C-meso-L or C-racemic-L (L = 5,5,7,12,12,14hexamethyl-1,4,8,11-tetraazacyclotetradecane). Both C-meso-L and C-racemic-L react with copper(II) ion to form [Cu(C-meso-L)] or [Cu(C-racemic-L)] in dehydrated ethanol, but do not with nickel(II) ion under similar conditions. Crystal structure of [Cu(C-racemic-L)(H2O)](ClO4)2 shows that the complex has distorted square-pyramidal coordination geometry with an apically coordinated water molecule. Unexpectedly, the Cu-N distances [2.016(3)-2.030(3) A] of [Cu(C-racemic-L)(H2O)](ClO4)2 are longer than those [1.992(3)2.000(3) A] of [Cu(C-racemic-L)(H2O)](ClO4)2. As a result, [Cu(C-racemic-L)(H2O)] exhibits weaker ligand field strength than [Cu(C-racemic-L)(H2O)]. The copper(II) complexes readily react with CN ion to yield the cyano-bridged dinuclear complex [Cu2(C-meso-L)2CN] or [Cu2(C-racemic-L)2CN]. Spectra and chemical properties of [Cu(C-meso-L)] and [Cu2(C-meso-L)2CN] are not quite different from those of [Cu(C-racemic-L)] and [Cu2(C-racemic-L)2CN], respectively.

Novel dichloro zinc complexes based on enantiopure N,N-diamine ligands bearing furanylmethyl and thiophenylmethyl pendent groups were synthesised, and their crystal structures were determined using X-ray crystallography. The isopropoxide derivatives (generated in situ) of these well-characterised complexes efficiently catalysed the ring-opening polymerisation (ROP) of rac-lactide (rac-LA) at two different temperatures under controlled conditions. Highly heterotactic polylactide (PLA) was obtained with Pr = 0.80 at −25 °C in THF.

Novel enantiopure Cu(II) complexes of (R,R)-N1,N2-dimethyl-bis(naphthalen-1-ylmethyl)cyclohexane-1,2-diamine (1-NMCD) and (R,R)-N1,N2-dimethyl-bis(naphthalen-2-ylmethyl)cyclohexane-1,2-diamine (2-NMCD) ligands were synthesized and characterized by X-ray diffraction. X-ray diffraction analysis revealed that the molecular structures of the synthesized complexes were mononuclear with Cu(II) atoms in distorted square planar geometries. The diisopropoxide derivatives generated in situ catalyzed ring opening polymerization (ROP) of rac-lactide (rac-LA) in a controlled fashion and displayed unusually high activities (10 s or 25 s for complete conversion). Heterotactic enriched PLA (with Pr up to 0.90) was obtained with initiator bearing 2-NMCD in CH2Cl2.

Two novel dichlorozinc complexes, (peeda)ZnCl2 and (pepda)ZnCl2, where peeda is N1,N2-bis{(R)-1-phenylethyl}ethane-1,2-diamine and pepda is N1,N3-bis{(R)-1-phenylethyl}propane-1,3-diamine, were synthesised and characterised by X-ray diffraction. Dialkyl derivatives of these compounds, generated in situ, efficiently initiated the ring-opening polymerisation (ROP) of rac-lactide (rac-LA). The backbone links, composed of diamine units, had a significant influence on the degree of stereoselectivity in the resulting heterotactic polylactide (PLA). Increased flexibility of the diamine backbone resulted in enhanced heterotacticity. (pepda)ZnMe2 produced heterotactic PLA with a Pr of 0.78 at −25 °C.

Complexation of FeCl 2 ·4H 2 O with N , N -Bis{(1-H pyrazole-1-yl)methyl}aniline [bpmaL 1 ] gave air-stable dichloro-bridged binuclear iron(II) species ( 1a ) having five-coordinated iron, which was characterised by X-ray crystallography and magnetic susceptibility. The geometry at each iron centre of 1a is a distorted trigonal bipyramid with two equivalent half-molecules providing overall C i symmetry. One of the pyrazolyl nitrogen atoms (N1) and a chlorine atom (Cl2) # form one apex of the distorted trigonal bipyramid. The magnetic parameters indicated only a weak antiferromagnetic coupling, despite the presence of two chloro ions, and dominant zero-field-splitting parameters. The relatively long Fe⋯Fe distance of 3.8118(6) A within the chloro-bridged dimer excludes direct interaction between the iron(II) ions. Thus, the antiferromagnetic coupling between the two iron(II) ions of 1a is attributed to superexchange through the chloride ions. Compared to the analogous cobalt complexes, the activity of α-olefin polymerization towards ethylene, norbornene, 1-octene and methyl methacrylate (MMA) was virtually zero, 1a is the first bis-pyrazole based dinuclear and five-coordinated iron(II) complex.

New nanoporous TiO2–MoO3 hybrids have been successfully synthesized via an exfoliation and reassembling method. According to the X-ray diffraction (XRD) pattern and transmission electron microscopy (TEM) analysis, quantum-sized titania nanoparticles with an average size of 1 nm were intercalated into the interlayer spaces of layered MoO3. Such a regularity of pillars results in a remarkable enhancement of the specific surface area, as confirmed by nitrogen adsorption–desorption measurements. The Langmuir specific surface area (210 m2 g−1) of TiO2-pillared MoO3 hybrid has been determined to be considerably larger than that (10 m2 g−1) of the self-restacked MoO3. It is evident that adequate intercalation of TiO2 nanoparticles into a MoO3 lattice gives rise to a highly nanoporous structure. The photocatalytic activity of the present nanoporous hybrid is much superior to that of layered molybdenum oxide alone in terms of the degradation of organic pollutant.

Syngas production in Gas-to-liquid (GTL) process is focused in past by several researchers to increase the production with minimal capital and operating costs. In this study, syngas production process is simulated and optimized to increase its production and the economic analysis is studied for the proposed optimized process. Aspen HYSYS v8.4 is used for all process simulation work in this article. A new configuration is rigorously simulated while using auto-thermal reforming. Results exhibit a tremendous rise in production of syngas.

Two di-N-functionalized macrocyclic complexes, [Ni(C-racemic-L3)]2+ bearing two N CH2CH2C( NH)OCH3 pendant arms and [Ni(C-racemic-L8)]2+ bearing two N CH2C( NH)OCH3 pendant arms, have been prepared by the reaction of methanol with [Ni(C-racemic-L2)(OAc)]+ (L2 = 1,8-bis(N-cyanoethyl)-5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane) or [Ni(C-racemic-L7)(OAc)]+ (L7 = 1,8-bis(N-cyanomethyl)-5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane). Both complexes have somewhat distorted cis-octahedral coordination geometry. Their hydrolysis has been investigated under various experimental conditions. The complex [Ni(C-racemic-L3)]2+ is hydrolyzed to [Ni(C-racemic-L4)]2+ bearing two N CH2CH2COOCH3 groups in acidic aqueous solutions (pH ⩽6), but to [Ni(C-racemic-L5)]2+ bearing two N (CH2)2CONH2 pendant arms in basic aqueous solutions (pH ⩾9). Very interestingly, two N (CH2)2C( NH)OMe groups in [Ni(C-racemic-L3)]2+ undergo different reactions at pH 7 to yield [Ni(C-racemic-L6)]2+ bearing one N (CH2)2CONH2 and one N (CH2)2CN pendant arms. Although the N CH2C( NH)OCH3 groups in [Ni(C-racemic-L8)]2+ undergo hydrolysis to form [Ni(C-racemic-L9)]2+ bearing two N CH2CONH2 pendant arms in basic aqueous solutions (pH ⩾9), they are quite inert against hydrolysis in neutral and acidic aqueous solutions (pH ⩽7).

Dichloro zinc complexes with ( S )-1-phenyl- N -[( S )-1-(pyridin-2-yl)ethyl]ethanamine (PMMA) and ( S )-1-(6-methylpyridin-2-yl)- N -[( S )-1-phenylethyl]ethanamine (MPMMA) were prepared and characterised by X-ray diffraction. The catalytic activity of the dimethyl complexes, generated in situ , was high in the ring opening polymerization of rac -lactide. Specifically, the dimethyl derivative of (PMMA)ZnCl 2 yielded a highly stereocontrolled polylactide with P r = 0.84.

A novel dichloro zinc complex (L1)ZnCl2, where L1 is N,N′-bis-(2,6-dichloro-benzyl)-(R,R)-1,2-diaminocyclohexane, has been synthesized and characterized. The dimethyl derivatives, generated in situ from the well characterized dichloro zinc complexes (L1)ZnCl2 and (L2)ZnCl2, where L2 is N,N′-bis-(benzyl)-(R,R)-1,2-diaminocyclohexane, were employed as initiators for the ring opening polymerization (ROP) of rac-lactide (rac-LA). The complexes were found to be highly efficient initiators yielding the polylactide (PLA) with a narrow molecular weight distribution. The catalytic activity and heterotactic selectivity of the Zn(II) complexes were affected by the substituents on the phenyl groups of benzyl moieties in (R,R)-1,2-diaminocyclohexane. The dimethyl derivative of (L2)ZnCl2 produced highly stereocontrolled PLA with Pr = 0.75 at −25 °C.