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111.
Sabrina Marie Martin Lutz Anthony L. Spek Robertus J.M. Klein Gebbink Gerard van Koten Nelly Kervarec Franois Michaud Jean-Yves Salaün Paul-Alain Jaffrs 《Journal of organometallic chemistry》2009,694(25):4001-4007
The O,O-diethyl thiophosphonate functional group has been introduced on position 2 of a pyrrole heterocycle following a two steps sequence that makes use of a [1,2] base-induced rearrangement applied for the first time to a O,O-diethyl thiophosphoramide intermediate. This rearrangement has been studied by low temperature NMR and the intermediates have been fully characterized. The coordination of this monoanionic bidentate (N,Ssp2) ligand to silver or palladium is studied The bidentate ligand 2 (O,O-diethyl pyrrol-2-ylthiophosphonate), associated with a palladium precursor, produces in the presence of triethylamine the complex trans-[Pd(η2-2′)2] 3 (2′ is deprotonated ligand 2). Ligand 2 also reacts with silver oxide in dichloromethane to give an unstable complex 2′-Ag that can be stabilized by addition of triphenylphosphine to produce the coordination complex 4 [Ag((η2-2′)(PPh3)2]. 相似文献
112.
Oleksenko Ludmila Fedorenko George Maksymovych Nelly 《Research on Chemical Intermediates》2019,45(8):4101-4111
Research on Chemical Intermediates - Nanosized semiconductive Pd-containing sensor materials based on SnO2 were obtained by sol–gel technique. The highly sensitive gas sensor based on... 相似文献
113.
Cylindrical liquid jets are inherently unstable and eventually break into drops due to the Rayleigh-Plateau instability, characterized by the growth of disturbances that are either convective or absolute in nature. Convective instabilities grow in amplitude as they are swept along by the flow, while absolute instabilities are disturbances that grow at a fixed spatial location. Liquid jets are nearly always convectively unstable. Here we show that two-phase jets can breakup due to an absolute instability that depends on the capillary number of the outer liquid, provided the Weber number of the inner liquid is >O(1). We verify our experimental observations with a linear stability analysis. 相似文献
114.
Identification and quantification of bisphenol A and bisphenol B in polyvinylchloride and polycarbonate medical devices by gas chromatography with mass spectrometry
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Pascal Gimeno Coline Spinau Nelly Lassu Annie‐Franoise Maggio Charlotte Brenier Laurent Lempereur 《Journal of separation science》2015,38(21):3727-3734
A gas chromatography with mass spectrometry method has already been developed and published for the identification and quantification of 14 phthalates and five nonphthalate plasticizers in polyvinylchloride medical devices. In order to assay, in addition to plasticizers, bisphenols A and B possibly present in polyvinylchloride samples, this previous method was extended to the assay of these additional potential endocrine disruptors. Furthermore, as bisphenol A could also be present in polycarbonate samples, the method used for the polyvinylchloride sample was tested and validated for the assay of bisphenols A and B in polycarbonate medical devices. The separation of all compounds, including bisphenols A and B, is obtained on a cross‐linked 5%‐phenyl/95%‐dimethylpolysiloxane capillary column using a temperature gradient. For both plastics, samples are dissolved in tetrahydrofuran followed by a precipitation of the plastic by addition of ethanol. Results obtained point out residual bisphenol A amounts for polycarbonate samples ranging from 0.6 to 0.8% and for polyvinylchloride samples less or equal to 5 ppm. No bisphenol B was detected in the samples tested. For bisphenols A and B, mean recoveries obtained on spiked polyvinylchloride or polycarbonate sample preparations ranged from 87 to 108% in accordance with in‐house specification (80–110%). 相似文献
115.
Nelly Jorge N lida Peruchena L zaro Cafferata Eduardo A. Castro 《Journal of Molecular Structure》1994,309(3):315-324
We have made a conformational study of tetroxane and its bi- and tetra-halogenated derivatives by means of the semiempirical AM1 and PM3 molecular orbital methods. The results are compared with previous semiempirical and ab initio studies as well as with available experimental data. We have found that in every case the AM1 method underestimates the peroxidic O-O bond length by approximately 12%, while the PM3 procedure describes such a bond in a better way. The degree of accuracy of these two semiempirical methods is discussed in relation with the tetroxane structure. 相似文献
116.
(Accepted July 23, 1996) 相似文献
117.
The volatile components of the flowerheads of Centaurea eryngioides Lam. and Centaurea iberica Trev. var. hermonis Boiss. Lam. were obtained by hydrodistillation and identified by GC and GC-MS. Altogether 91 components, mostly fatty acids and hydrocarbons, were identified. 相似文献
118.
Julia E. Morozova Ella Kh. Kazakova Eduard Ph. Gubanov Nelly A. Makarova Victor P. Archipov Tatjana V. Timoshina Zaymil Sh. Idijatullin Wolf D. Habicher Alexander I. Konovalov 《Journal of inclusion phenomena and macrocyclic chemistry》2006,55(1-2):173-183
Present paper reports on tensiometric studies of tetramethylsulfonatoresorcinarenes 1 and 2 with nonionogenic guests 3 and 4, pyrimidin derivative and O,O-dymethyl-1,1-dimethyl-3-oxobutylphosphonate, respectively. Association of resorcinarenes with these guests leads to dramatic change of adsorption characteristics of their solutions. CCMs1 of associates (1&3, 1&4, 2&3, and 2&4) are lower and the estimated surface activity, as well as the height of adsorption layers are higher than for individual substances. Aggregation of compounds 1–4 and association of 1 with 3 and 4 in solution were confirmed by 1H NMR spectra and studied by diffusion NMR with impulse magnetic field gradient. 相似文献
119.
Nury PérezBarbara Gordillo 《Tetrahedron》2003,59(5):671-676
(±)-r-7-Benzyloxymethyl-cyclopenta-cis-[4,5][1,3]-oxazolo[3,2-a]pyrimidinones were synthesized in two steps from 1-hydroxymethyl-3-cyclopentene. These compounds are versatile intermediates for the synthesis of carbocyclic nucleosides. The synthesis has been accomplished by the iodofunctionalization of olefins as a method of coupling the pyrimidine bases and the carbocycle. 相似文献
120.
Bruno M Rosselli S Maggio A Piozzi F Scaglioni L Arnold NA Simmonds MS 《Chemical & pharmaceutical bulletin》2004,52(12):1497-1500
Two new neoclerodane diterpenoids, 6-deacetyl-teucrolivin A (5) and 8beta-hydroxy-teucrolivin B (6), were isolated from the aerial parts of Teucrium orientale, along with four already known neoclerodane diterpenoids, teucrolivin A (1), teucrolivin B (2), teucrolivin C (3) and teucrolivin H (4), previously isolated from Teucrium oliverianum. Their structures were elucidated on the basis of spectroscopic evidence and chemical transformations. Compounds 1-3 were assayed for antifeedant activity against Spodoptera littoralis, S. frugiperda and Heliocoverpa armigera. Teucrolivin A was the most potent of the three compounds tested. 相似文献