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1.
Angew Chem Int Ed Engl ; 62(27): e202305225, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37104116

RESUMO

Porous organic polymers (POPs) with high porosity and tunable functionalities have been widely studied for use in gas separation, catalysis, energy conversion and energy storage. However, the high cost of organic monomers, and the use of toxic solvents and high temperatures during synthesis pose obstacles for large-scale production. Herein, we report the synthesis of imine and aminal-linked POPs using inexpensive diamine and dialdehyde monomers in green solvents. Theoretical calculations and control experiments show that using meta-diamines is crucial for forming aminal linkages and branching porous networks from [2+2] polycondensation reactions. The method demonstrates good generality in that 6 POPs were successfully synthesized from different monomers. Additionally, we scaled up the synthesis in ethanol at room temperature, resulting in the production of POPs in sub-kilogram quantities at a relatively low cost. Proof-of-concept studies demonstrate that the POPs can be used as high-performance sorbents for CO2 separation and as porous substrates for efficient heterogeneous catalysis. This method provides an environmentally friendly and cost-effective approach for large-scale synthesis of various POPs.

2.
Org Biomol Chem ; 19(44): 9645-9648, 2021 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-34730170

RESUMO

[3 + 2] annulations of oxindole based spirocyclic donor-acceptor cyclopropanes and ynamides catalyzed by copper triflate have been developed for the synthesis of biologically important spirocyclopenteneoxindoles. These reactions tolerated a wide scope of substrates and provided the desired products in good to high yields (up to 90%) with up to >40 : 1 diastereoselectivities under mild conditions.

3.
J Org Chem ; 85(21): 14262-14270, 2020 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-33115228

RESUMO

1,6-Dicarbonyl compounds, representing the formal addition products of the α-position of acetophenone derivatives to donor-acceptor cyclopropanes, were synthesized in two steps via first ring opening of donor-acceptor cyclopropanes with acyclic 1,3-diketones followed by DBU catalyzed retro-Claisen-type C-C bond cleavage reactions. In the first step, acyclic 1,3-diketones selectively worked as C-nucleophiles to add to donor-acceptor cyclopropanes. In the second step, the alkyl ketone part of the ring-opening products resulting from unsymmetrical 1,3-diketones was selectively cleaved in the presence of DBU in methanol.

4.
J Org Chem ; 85(9): 5778-5786, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32255650

RESUMO

A new type of 1-unsymmetrical D-A cyclopropanes containing a cyclic enone motif was obtained by the desymmetrization of 1-symmetrical D-A cyclopropanes via first the Lewis acid-catalyzed O-nucleophilic ring-opening reaction with 1,3-cyclodiones followed by an organobase-promoted unexpected multistep intramolecular transformation.

5.
Inorg Chem ; 59(4): 2121-2126, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-31999108

RESUMO

Interlinking discrete supertetrahedral chalcogenolate clusters with conjugated bipyridine linkers form a one-dimensional coordination polymer, [Cd6Ag4(SPh)16(DMF)(H2O)(bpe)]n (1a), displaying a broader visible-light absorption and a narrower band gap than those of the discrete cluster. More importantly, the coordination polymer demonstrates enhanced activity and stability for the photocatalytic degradation of organic dye in water.

6.
Org Biomol Chem ; 18(33): 6492-6496, 2020 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-32785321

RESUMO

1,3-Cyclohexandione derived cyclic ketals and thiol ketals were used as O- and S-nucleophiles, respectively, for the ring opening of donor-acceptor cyclopropanes catalyzed by Cu(OTf)2 and a series of functionalized alkylene glycol diethers and dithiol diethers were obtained in good to high yields under mild conditions.

8.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 6): m343, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23795003

RESUMO

The structure of the title complex, [FeRu(C5H5)(C5H4OPS2)(CO)(C18H15P)2(H2O)]·CH2Cl2, consists of one neutral [{FcP(O)S2}Ru(CO)(H2O)(PPh3)2] complex [Fc = Fe(η(5)-C5H4)(η(5)-C5H5)] and one CH2Cl2 solvent mol-ecule. The geometry around the Ru(II) atom is pseudo-octa-hedral, with two cis-binding PPh3 ligands and one chelating bidentate [Fc(O)PS2](2-) ligand via two S atoms. The average Ru-S and Ru-P bond lengths are 2.434 (1) and 2.398 (1) Å, and the Ru-O and Ru-C bond lengths are 2.157 (3) and 1.826 (4) Å, respectively. In the crystal, pairs of O-H⋯O hydrogen bonds link adjacent mol-ecules into dimers.

9.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 6): m344, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23795004

RESUMO

The title complex salt, (C8H20N)[ZnCl3(C3H7NO)], contains one [Et4N](+) cation (Et is ethyl) and one [ZnCl3(DMF)](-) anion (DMF is di-methyl-formamide). In the anion, the zinc atom is tetra-hedrally coordinated by a DMF ligand via the O atom and by three terminal Cl atoms. The average Zn-Cl bond length and Cl-Zn-Cl angle are 2.243 (11) Šand 114 (3)°, respectively.

10.
Artigo em Inglês | MEDLINE | ID: mdl-24046715

RESUMO

The asymmetric unit of the title compound, C38H34Cl2O2Te2·H2O, contains two independent Te(IV) cations, each coordinated by three phenyl ligands, two Cl(-) anions and one acetic acid mol-ecule in a distorted octa-hedral C3Cl2O geometry; the longer Te⋯Cl distances ranging from 3.2007 (11) to 3.4407 (11) Šand the longer Te⋯O distances of 3.067 (3) and 3.113 (3) Šindicate the weak bridge coordination. The Cl(-) anion and acetic acid mol-ecule bridge the two independent Te(IV) cations, forming the dimeric complex mol-ecule, in which the Te⋯Te separation is 3.7314 (4) Å. In the crystal, the water molecules of crystallization link the Te(IV) complex mol-ecules into chains running along the b-axis direction via O-H⋯O and O-H⋯Cl hydrogen bonds.

11.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 2): m105, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23424402

RESUMO

The title complex, [RuBr(2)(C(5)H(5)N)(4)], contains two independent complex mol-ecules in each of which the Ru(II) atom is located on a site of 222 symmetry and has a distorted octa-hedral coordination geometry with four pyridine N atoms and two Br atoms. The Br aroms are trans-disposed as a result of symmetry.

12.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 6): m340, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23795000

RESUMO

In the title complex, [RuCl2(CH3CN)3(C18H15P)]·CH3CN, the coordination geometry of the Ru(II) atom is distorted octa-hedral, defined by one P atom from a tri-phenyl-phosphane ligand, three N atoms from three aceto-nitrile ligands and two Cl atoms. The three acetronitile ligands linearly bind to the Ru(II) atom, with Ru-N-C angles of 172.6 (2), 179.9 (2) and 171.4 (2)°.

13.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 6): m341, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23795001

RESUMO

In the title complex, [Ru(C6H14O2PS2)3], the coordination environment of the Ru(III) atom is distorted octa-hedral, defined by six S atoms from three S,S'-bidentate diisopropyl di-thio-phosphate ligands. The average Ru-S bond length is 2.41 (1) Šand the average S-Ru-S bite angle is 81.13 (19)°.

14.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 6): m342, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23795002

RESUMO

In the title coordination polymer, [Ag2Cl2(C10H8N2)(C18H15P)2] n , the Ag(I) cation is coordinated by a 4,4'-bi-pyridine N atom, a tri-phenyl-phosphane P atom and two Cl(-) anions in a distorted tetra-hedral geometry. The 4,4-bi-pyridine and Cl(-) anions bridge the Ag(I) cations, forming polymeric chains running along [21-1]. In the crystal, weak C-H⋯Cl inter-actions link the polymeric chains into a three-dimensiona supra-molecular architecture.

15.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 11): m608, 2013 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-24454038

RESUMO

The title compound, {(C6H8N)[AgWSe4]·C6H7N} n , consists of anionic [WAgSe4] n chains, 2-methyl-pyridinium cations and neutral 2-methyl-pyridine mol-ecules. The Se atoms bridge the Ag and W atoms, forming a polymeric chain extending along the b-axis direction. Both the Ag and W atoms are located on a twofold rotation axis and each metal atom is coordinated by four Se atoms in distorted tetra-hedral geometry. In the crystal, the 2-methyl-pyridinium cation and 2-methyl-pyridine mol-ecule are linked via N-H⋯N hydrogen bonding. Weak C-H⋯Se inter-actions link the organic components and polymeric anions into a three-dimensional architecture.

16.
Artigo em Inglês | MEDLINE | ID: mdl-24046575

RESUMO

In the title complex, [Mn(C20H14N2O2)Cl]·CH3OH, the central Mn(III) atom displays a distorted square-pyramidal coordination by two N and two O atoms from the tetradentate 2,2'-[1,2-phenyl-enebis(nitrilo-methanylyl-idyne)]diphenolate ligand and one chloride ligand. The Mn(III) atom is 0.525 (4) Šout of the square basal N2O2 least-squares plane. The complex mol-ecule is hydrogen bonded to the methanol solvent mol-ecule.

17.
RSC Adv ; 13(11): 7432-7435, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36895764

RESUMO

Asymmetric ring-opening reactions of donor-acceptor cyclopropanes with 1,3-cyclodiones have been established for the synthesis of enantioenriched γ-hydroxybutyric acid derivatives in the presence of Cu(ii)/trisoxazoline catalyst. These reactions offered the desired products in 70% to 93% yields with 79% to 99% enantiomeric excesses.

18.
Luminescence ; 27(5): 414-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21990159

RESUMO

Chemiluminescence (CL) of a cyclometallated iridium (III) complex {tris[1-(2,6-dimethylphenoxy)-4-(4-chlorophenyl)phthalazine]iridium(III)} in the presence of potassium permanganate and oxalic acid is reported for the first time. Cysteine exhibits sufficient enhancing effect on the CL generated from the cyclometallated iridium(III) complex, which make it possible for the sensitive detection of cysteine using a flow-injection-chemiluminescence (FI-CL) method. The optimum conditions for the chemiluminescence emission were investigated. Under the optimal condition, the linear range for the determination of cysteine was 1.0 × 10(-9) -5.0 × 10(-6) mol/L with a detection limit of 6.9 × 10(-10) mol/L. A relative standard deviation of 1.6% was obtained for eight replicate determinations. The mechanisms of CL are proposed and the emitting species was identified as the metal-to-ligand charge-transfer (MLCT) excited states of the iridium complex.


Assuntos
Cisteína/análise , Irídio/química , Substâncias Luminescentes/química , Medições Luminescentes
19.
Luminescence ; 27(4): 262-7, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21842518

RESUMO

A novel chemiluminescence (CL) system, including the cyclometallated iridium(III) complex {tris[1-(2,6-dimethylphenoxy)-4-(4-chlorophenyl)phthalazine]iridium}, potassium permanganate and oxalic acid, is proposed for the determination of benzenediols. This method is based on the fact that hydroquinone and catechol exhibited an inhibiting effect, while resorcinol exhibited an enhancing effect on CL intensity. The optimum conditions for CL emission were investigated. Under optimal conditions, the detection limits of hydroquinone, catechol and resorcinol were 6.4 × 10(-8), 2.7 × 10(-9) and 8.1 × 10(-7) mol/L, respectively. The method has been successfully applied to the determination of benzenediols in different types of water sample. The luminophors of the CL systems were all identified as the metal-ligand charge-transfer (MLCT) excited state of the iridium complex.


Assuntos
Irídio/química , Medições Luminescentes/métodos , Compostos Organometálicos/química , Fenóis/química , Cinética
20.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 3): m297, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22412440

RESUMO

In the title complex, [CuCl(C(14)H(12)N(4))(2)], the Cu(I) atom, lying on a twofold rotation axis, is coordinated by two N atoms of two 1,2,3,4-tetra-hydro-1,4,6,11-tetra-aza-naphthacene ligands and one Cl atom, also lying on the twofold rotation axis, in a distorted trigonal-planar geometry. The complex mol-ecules are connected into a one-dimensional structure along [001] via N-H⋯N hydrogen bonds and further into a three-dimensional structure via N-H⋯Cl hydrogen bonds. π-π inter-actions between the pyrazine and benzene rings and between the benzene rings [centroid-centroid distances = 3.5635 (15) and 3.9128 (16) Å] are present.

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