Six diiron ethanedithiolate complexes containing benzoate ester have been synthesized and characterized. Treatment of the starting material {μ‐SCH2CH(CH2OH)S}Fe2(CO)6 (1) with benzoic acid in the ...presence of N,N′‐dicyclohexylcarbodiimide and 4‐dimethylaminopyridine afforded the benzoate ester‐containing complex {μ‐SCH2CH(CH2O2CPh)S}Fe2(CO)6 (2) in 97% yield. Carbonyl substitution of complex 2 with a monophosphine ligand, such as triphenylphosphine, tris(2‐methoxyphenyl)phosphine, tris(4‐fluorophenyl)phosphine, isopropyldiphenylphosphine or cyclohexyldiphenylphosphine, in the presence of Me3NO⋅2H2O gave the derivatives {μ‐SCH2CH(CH2O2CPh)S}Fe2(CO)5L (L = PPh3, 3; P(C6H4OCH3‐2)3, 4; P(C6H4F‐4)3, 5; Ph2PCH(CH3)2, 6; Ph2PC6H11, 7) in 66–95% yields. Complexes 2–7 were characterized using elemental analysis, spectroscopy and X‐ray diffraction analysis. In addition, these complexes can catalyze the reduction of protons to H2 in the presence of weak acid HOAc under electrochemical conditions.
Six diiron complexes were prepared by esterification or carbonyl substitution and structurally characterized using elemental analysis, infrared and NMR spectroscopies and X‐ray crystallography. In addition, the electrochemical properties of the complexes were studied using cyclic voltammetry.
Five monophosphine‐substituted diiron propane‐1,2‐dithiolate complexes as the active site models of FeFe‐hydrogenases have been synthesized and characterized. Reactions of complex ...Fe2(CO)6{μ‐SCH2CH(CH3)S} (1) with a monophosphine ligand tris(4‐methylphenyl)phosphine, diphenyl‐2‐pyridylphosphine, tris(4‐chlorophenyl)phosphine, triphenylphosphine, or tris(4‐fluorophenyl)phosphine in the presence of the oxidative agent Me3NO·2H2O gave the monophosphine‐substituted diiron complexes Fe2(CO)5(L){μ‐SCH2CH(CH3)S} L = P(4‐C6H4CH3)3, 2; Ph2P(2‐C5H4N), 3; P(4‐C6H4Cl)3, 4; PPh3, 5; P(4‐C6H4F)3, 6 in 81%–94% yields. Complexes 2–6 have been characterized by elemental analysis, spectroscopy, and X‐ray crystallography. In addition, electrochemical studies revealed that these complexes can catalyze the reduction of protons to H2 in the presence of HOAc.
Five diiron propane‐1,2‐dithiolate complexes have been prepared by CO substitution and structurally characterized by elemental analysis, infrared, nuclear magnetic resonance, and X‐ray crystallography. In addition, the electrochemical properties of these complexes were studied by cyclic voltammetry.
A series of triazole derivatives containing a pyrazole moiety were synthesized and characterized by 1H NMR, 13C NMR, and HRMS. The herbicidal activities of these compounds were tested against lettuce ...and bentgrass. Most of the tested compounds were moderately herbicidal activity against lettuce and bentgrass. Among them, compounds 6f and 6g had the highest herbicidal activity (80% inhibitory) against lettuce and bentgrass.
Several new 1,3,4-oxadiazole derivatives containing a pyrazole ring were designed and synthesized from ethyl acetoacetate and triethyl orthoformate as starting materials via multi-step reactions. The ...compound structures were confirmed by melting point,
1
H NMR and HRMS. They were evaluated for fungicidal and herbicidal activities. Four of the compounds exhibited moderate fungicidal activity against
Colletotrichum
species. Most of the compounds had moderate-to-good activity as a herbicide.
In order to investigate the biological activity of novel 1,2,4-triazole compounds, seventeen novel 1,2,4-triazole derivatives containing pyridine moiety were synthesized under microwave assistant ...condition by multi-step reactions. The structures were characterized by 1H NMR, MS and elemental analyses. The target compounds were evaluated for their fungicidal activities against Stemphylium lycopersici (Enjoji) Yamamoto, Fusarium oxysporum. sp. cucumebrium, and Botrytis cinerea in vivo, and the results indicated that some of the title compounds displayed excellent fungicidal activities. Theoretical calculation of the title compound was carried out with B3LYP/6-31G (d,p). The full geometry optimization was carried out using 6-31G (d,p) basis set, and the frontier orbital energy, atomic net charges were discussed, and the structure-activity relationship was also studied.
Natural products are a source of many novel compounds with biological activity for the discovery of new pesticides and pharmaceuticals. Quinoxaline is a fused N-heterocycle in many natural products ...and synthetic compounds, and seven novel quinoxaline derivatives were designed and synthesized via three steps. Pesticidal activities of title quinoxaline derivatives were bioassayed. Most of these compounds had herbicidal, fungicidal, and insecticidal activities. The compounds 2-(6-methoxy-2-oxo-3-phenylquinoxalin-1(2H)-yl)acetonitrile (3f) and 1-allyl-6-methoxy-3-phenylquinoxalin-2(1H)-one (3g) were the most active herbicides and fungicides. Mode-of-action studies indicated that 3f is a protoprophyrinogen oxidase-inhibiting herbicide. Compound 3f also possessed broad-spectrum fungicidal activity against the plant pathogen Colletotrichum species. Some of these compounds also had insecticidal activity. Molecular docking and DFT analysis can potentially be used to design more active compounds.
In this article, five diiron 1,2-dithiolate complexes containing phosphine ligands are reported. Treatment of complex Fe
2
(CO)
6
(μ-SCH
2
CH
2
S) (1) with the phosphine ligands ...tris(4-methylphenyl)phosphine, tris(4-methoxyphenyl)phosphine, tris(3-chlorophenyl)phosphine, tris(3-methylphenyl)phosphine, or 2-(diphenylphosphino)biphenyl in the presence of Me
3
NO·2H
2
O as the decarbonylating agent afforded the target products Fe
2
(CO)
5
(L)(μ-SCH
2
CH
2
S) L = P(4-C
6
H
4
CH
3
)
3
, 2; P(4-C
6
H
4
OCH
3
)
3
, 3; P(3-C
6
H
4
Cl)
3
, 4; P(3-C
6
H
4
CH
3
)
3
, 5; Ph
2
P(2-C
6
H
4
Ph), 6 in 80-93% yields. Complexes 2-6 have been characterized by elemental analysis, spectroscopy, and X-ray crystallography. Additionally, the electrochemical properties were studied by cyclic voltammetry.
In this paper, five diiron propane-1,3-dithiolate complexes containing substituted phosphine ligands were prepared and structurally characterized. Treatment of Fe
2
(CO)
6
(μ-SCH
2
CH
2
CH
2
S) (1) ...with a monophosphine ligand methyl diphenylphosphinite, ethyl diphenylphosphinite, 4-(dimethylamino)phenyldiphenylphosphine, tris(2-methoxyphenyl)phosphine, or tris(4-chlorophenyl)phosphine in the presence of Me
3
NO·2H
2
O as the decarbonylating agent gave the corresponding phosphine-substituted analogues Fe
2
(CO)
5
(L)(μ-SCH
2
CH
2
CH
2
S) L = Ph
2
POCH
3
, 2; Ph
2
POCH
2
CH
3
, 3; Ph
2
P(4-C
6
H
4
NMe
2
), 4; P(2-C
6
H
4
OCH
3
)
3
, 5; P(4-C
6
H
4
Cl)
3
, 6 in 73-93% yields. Complexes 2-6 have been characterized by elemental analysis, spectroscopy, and X-ray crystallography. Additionally, electrochemical studies have shown that 2-6 can catalyze the reduction of protons to H
2
in the presence of HOAc.
The reactions of the starting complex, Fe
2
(CO)
6
{μ-SCH
2
CH (CH
2
CH
3
)S} (1), with the phosphine ligands tris(4-methylphenyl)phosphine, diphenyl-2-pyridylphosphine, ...tris(4-fluorophenyl)phosphine, 2-(diphenylphosphino)benzaldehyde, or benzyldiphenylphosphine in the presence of the decarbonylating agent Me
3
NO·2H
2
O yielded the corresponding phosphine-substituted diiron butane-1,2-dithiolate complexes Fe
2
(CO)
5
(L){μ-SCH
2
CH(CH
2
CH
3
)S} (L = P(4-C
6
H
4
CH
3
)
3
, 2; Ph
2
P(2-C
5
H
4
N), 3; P(4-C
6
H
4
F)
3
, 4; Ph
2
P(2-C
6
H
4
CHO), 5; Ph
2
PCH
2
Ph, 6) in 75%-87% yields. The complexes have been characterized by elemental analysis, IR,
1
H, and
31
P{
1
H} NMR spectroscopy, as well as by single-crystal X-ray diffraction analysis. Moreover, the electrochemistry of 2-4 was studied by cyclic voltammetry, suggesting that they can catalyze the reduction of protons to H
2
in the presence of HOAc.
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