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1
Simple Synthesis of Dialkyl 2-(3-Oxo-3H-indol-2-yl)-but-2-enedioates
Yavari I., Dehghan S., Alborzi A., Mohtat B.
Polish Journal of Chemistry
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2005
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Vol. 79 / nr 5
845-850
EN
Triphenylphosphine undergoes a smooth addition reaction with dialkyl acetylenedicarboxylates in the presence of isatin or 5-bromoisatin to produce stable crystalline phosphorus ylides. These products exist as a mixture of two geometrical isomers. Dynamic NMR effects have been observed in the 1H NMR spectra of dimethyl 2-(2,3-dioxo-2,3-dihydro-1H-indol-1-yl)-3-(1,1,1-triphenyl-_5-phosphanylidene)-succinate. These ylides are converted to dialkyl 2-(3-oxo-3H-indol-2-yl)-but-2-enedioates in boiling toluene.
2
Multinuclear NMR and Thermal Studies of New Silver(I) Silylated Carboxylates with Triphenylphosphine
Szłyk E., Szymańska I., Szczęsny R.
Polish Journal of Chemistry
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2005
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Vol. 79 / nr 4
627-635
EN
Me3SiCH2COOAg, [Ag(Me3SiCH2COO)(PPh3)] and [Ag(Me3SiCH2CH2COO)(PPh3)] were prepared and characterized in solution by 1H, 13C, 29Si, 31P and 29Si, 31P CPMAS NMR. Spectral analysis suggests bidentate bridging carboxylates and monodentately bonded PPh3 in solution and in the solid state. Two crystallographically inequivalent molecules of PPh3 appeared in the solid state, what is evident from 31P CPMAS NMR. Thermal studies of both complexes demonstrate two stage decomposition process (exothermic followed by endothermic) with formation of metallic silver in the range 483-548 K. TGA/IR and MS studies of Me3SiCH2COOAg and [Ag(Me3SiCH2COO)(PPh3)] revealed volatile products of decomposition (CO2, Me3 Si-) and recombination reactions such as (Me3SiCH2CO)2O, (Me3Si)2O. The mechanism of complexes thermal decomposition is proposed.
3
Study on reduced degradation of tetraglyme in the presence of triphenylphosphine
Mosio-Mosiewski J., Podstawa W.
Polish Journal of Applied Chemistry
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2005
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Vol. 49, nr 4
263-270
EN
The results of the studies on degradation of tetraglyme in the presence of oxygen, are presented. The temperature effect on the volumes of light components and heavy components is discussed. Triphenylphosphine was found to inhibit the oxidative destruction process more efficiently than comercially employed 2,2-methylene-bis(6-tert-butyl-p-cresol).
PL
Przedstawiono wyniki badań nad degradacją tetraglymu w obecności tlenu. Przedyskutowano wpływ temperatury na ilość utworzonych składniów lekkich i ciężkich. Stwierdzono, że trifenylofosfina inhibituje proces utleniającej destrukcji bardziej efektywnie, niż stosowany przemysłowo 2,2–metyleno–bis(6–tert–butyl–p–krezol).
4
Synthesis of Fluorinated Dialkyl 1-Aryl-4-alkoxy-5-oxo-2,5-dihydro-1H-pyrrole-2,3-dicarboxylates
Yavari I., Nasiri F., Djahaniani H.
Polish Journal of Chemistry
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2004
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Vol. 78 / nr 10
1871-1876
EN
Alkyl 2-(2-fluoro-anilino)-2-oxo-acetates or ethyl 2-oxo-2-(trifluoromethylanilino)-acetate undergo a multistep reaction with dialkyl acetylenedicarboxylates in the presence of triphenylphosphine to produce dialkyl l-(2-fluorophenyl)-4-alkoxy-5-oxo-2,5-dihydro-1H-pyrrole-2,3-dicarboxylates or dialkyl 4-ethoxy-5-oxo-1-[2-(trifluoromethyl)-phenyl]-2,5-dihydro-1H-pyrrole-2,3-dicarboxylates in good yields. Dynamic NMR study of dimethyl 4-ethoxy-5-oxo-1-[2-(trifluoromethyl)-phenyl]-2,5-dihydro-1H-pyrrole- 2,3-dicarboxylate shows a fairly high energy barrier (DeltaG _ = 60.9 kJ mol-1) for rotation around the N-aryl single bond, which leads to an observable atropisomerism.
5
Structures and Spectral Properties of (O-sec.-Butyldithiocarbonatio-S,S') Bis(triphenylphosphine) Copper(I) and Silver(I) Complexes
Han Q, Yang X., Lu L., Wang X.
Polish Journal of Chemistry
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2004
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Vol. 78 / nr 1
27-33
EN
New complexes (PPh3)2M(S2COR) [R = sec.-butyl,M= copper (1), silver (2)] were synthesized by the reaction of excessive triphenylphosphine and copper(II) or silver(I) xanthate, and characterized using IR, EA, 1H NMR and TG. Their crystal structures have been determined by X-ray diffraction. The light yellow crystal of the complex (1) is triclinic of space group P1, with parameters a = 10.300(2) A, b = 13.120(3) A, c = 14.570(3)A, _= 89.53(3), _ = 72.81(3), _ = 78.61(3)_, and Z = 2. The yellow crystal of the complex (2) is triclinic of space group P1, with parameters a = 10.330(2) A, b = 13.410(3) A, c = 14.420(3) A, _ = 88.61(3), _ = 73.60(3), _ = 78.93(3)_, and Z = 2. In the two complexes, the central Cu or Ag atom is in a distorted tetrahedral environment and chelated by two phosphorus atoms from the triphenylphosphine groups and two sulfur atoms from the O-alkyldithiocarbonate. IR and 1H NMR results supported the structures. The thermal analytical data indicate that the complex (1) began to decompose at 122.3_ and decomposition was complete at 370.9_, leaving Cu2S, while the complex (2) began to decompose at 133.3_ and decomposed completely at 290.3_ to Ag2S.
6
Dimeric Silver(I) Complexes with Trimethylphosphine and Aliphatic Perfluorinated Carboxylates
Szłyk E., Łakomska I.
Polish Journal of Chemistry
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2002
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Vol. 76 / nr 10
1399-1403
EN
Silver(I) complexes with trimethylphosphine and perfluorinated carboxylates of general formula [{Ag(PMe3)2}2(_-OOCR)2], where R = CF3, C2F5, C3F7, C4F9, C7F15, have been prepared and characterized with IR, 1H, 13C, 19F, 31P NMR. Spectral analysis suggests four coordinated Ag(I) with two monodentate trimethylphosphine and bidentate carboxylates forming bridges between silver(I) ions. Thermal decomposition process was studied between 293-973 K in nitrogen. Decomposition proceeds in one exothermic stage corresponding to the elimination of perfluorinated carboxylate and trimethylphosphine. The final product was a mixture of metallic silver and carbon, formed between 473-633 K.
7
New Polymeric Copper(II) Complexes with Triphenyl Phosphite and Perfluorinated Carboxylates
Szłyk E., Szymańska I., Wrzeszcz G., Rozpłoch F.
Polish Journal of Chemistry
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2000
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Vol. 74, nr 7
909-918
EN
New Cu(II) complexes with triphenyl phosphite and aliphatic perfluorinated carboxylates [Cu{P(OC6H5)3}(u-OH)(u-RCOO)]n (where R=CF3, C2F5, C3F7, C6F13, C7F15, C8F17, C9F19) were obtainedf and their spectroscopic and thermal properties studied. EPR spectra and magnetic susceptibility measurments indicate the formation of polymeric complexes. Examination of COO absorption bands suggests bridging carboxylates as well as a hydro group, whereas triphenyl phosphite is monodentately bonded. Thermal decomposition is a multistage process, which in nitrogen yields a mixture of Cu, Cu2O and Cu2p2O7 but in air - pure u2P2O7.
8
Spectroscopic and Thermal Studies of Silver(I) Complexes with Aliphatic Carboxylates and Triphenylphosphine
Szłyk E., Łakomska I., Surdykowski A., Goliński A.
Polish Journal of Chemistry
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1999
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Vol. 73, nr 11
1763-1769
EN
Results of spectral analysis are in favour of Ag(I) trigonal coordination with unidentately bonded triphenylphosphine and bidentate carboxylates, forming bridges between silver(I) ions. Thermal decomposition was studied in 293-973 K range in nitrogen. The multistage decomposition initiates with the detachment of carboxylates and is followed by triphenylphosphine dissociation. The final product is metallic silver, formed between 605-683 K.
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