摘要:

AbstractLiterature describing the use of soluble metal–polymer catalysts in the molecular hydrogenation of alkenes, alkynes, aromatic and heterocyclic compounds has been reviewed. Special attention has been paid to coordinated metallic and organometallic catalytic systems and highly dispersed colloidal metals stabilized with polymers. The influence of metals, polymers and solvents on the structures of active sites is discussed. The prospects for the application of soluble metal–polymer catalysts in organic synthesis are also conside

ISSN:0268-2605    

DOI:10.1002/aoc.590040103

出版商:John Wiley&Sons Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractSeveral drugs (amphetamine, desipramine, nortriptyline, phenobarbital) have been labelled with metallocenic fragments in order to develop a new immunoassay method. The metallocenic fragments are cymantrenic or benchrotrenic derivatives: the linkage between the organic and organometallic moieties has been achieved by reactions between amino and acidic functional groups. All the products (metallohaptens), purified by different chromatography techniques, have been fully characterized by IR and1H NMR spectroscopy and their mass spectra.

ISSN:0268-2605    

DOI:10.1002/aoc.590040104

出版商:John Wiley&Sons Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractThe two ferrocene compounds, ferrocenylacetic acid (3) and ferrocylthiomalic acid (4), as well as the ferricenium salts, ferricenium tetrachloroferrate (III) (1) and ferricenium trichloroacetate–trichloroacetic acid solvate (2), were investigated by thein vitrohuman tumor clonogenic assay for their inhibiting effects, in continuous exposure in a double‐layer medium, on the colony formation of single‐cell suspensions prepared from 30 selected fresh specimens of human adenocarcinoma, squamous cell carcinoma and large‐cell carcinoma of the lung. At the high drug concentration level of 100 μg cm−3, good response ratios were observed for 3 (79%) and 4 (72%), followed by 1 (67%) and 2 (52%). At the low concentration level of 10 μg cm−3response ratios were below 25% for all compounds, best performance (24%) being shown by 1.In vitroexperiments probing the schedule dependencies of the compounds' inhibiting effects against the lung carcinoma cell line PC‐9 were also performed, as were experiments involving the combination of the ferricenium salt 1 and cisplatin, which showed the combination effect to be additive in both one‐hour and continuo

ISSN:0268-2605    

DOI:10.1002/aoc.590040105

出版商:John Wiley&Sons Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractPt(PPh3)2(CH2CH2) appeared to be a versatile catalyst in hydrosilylation of alkenes (with 5–22 C atoms) as well as of functionalized alkenes such as allyl chloride, allylamine, allyl methacrylate and vinylsilanes. In comparison with a well‐known Speier catalyst or with Pt(PPh3)4, this complex is characterized by a very high effectiveness (activity and selectivity) and relative resistance to oxygenation and it may be applied in recycling runs with a minor induction period. The catalytic processes examined are of great industrial importance since they lead to a synthesis of alkylsilanes, disilylethanes and silane coupling a

ISSN:0268-2605    

DOI:10.1002/aoc.590040106

出版商:John Wiley&Sons Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractNew types of surface‐active organocobaltocenium(I) complexes, η‐CnH2n+1X‐C5H4(ηC5H5)2Co+Y−and(η‐CnH2n+1X‐C5H4)Co+Y−(n= 6–16; X not present, NHCO or OCO; Y = Cl or PF6) were prepared and their surface character studied. (1) The critical micelle concentrations of the cobaltocenium chlorides were much lower than those of corresponding trimethylammonium‐type cationic surfactants. (2) The surface‐active character of the cobaltocenium chlorides in aqueous solution (and the redox potentials of the hexafluorophosphates in acetonitrile) were affected by the substituents (X) in the cyclopentadienyl groups. (3) The surface activities of the cobaltocenium salts were lost on reduction with NaBH4to afford (alkyl‐substituted cyclopentadiene) cyclopentadienylcobalt (0) complexes which were surface‐inactive but could be re‐oxidized to afford the surface‐active cobaltoceium(I) salts. The cobalt complexes mentioned above may be the first examples

ISSN:0268-2605    

DOI:10.1002/aoc.590040107

出版商:John Wiley&Sons Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractThe champignon mushroomAgaricus bisporuswas cultivated on compost labelled with the radioactive traers110mAg and203Hg and the uptake of these two metals studied. The radiotracer then served as an aid in elucidation and characterization of the fungal metal–protein species using gel chromatography. In the case of the silver–protein complex, but not of mercury, the majority of the metal was contained in the fractions of intermediate (ca8000–10000 Da) molecular weight possibly corresponding to metallothioneins (MT) or MT‐like

ISSN:0268-2605    

DOI:10.1002/aoc.590040108

出版商:John Wiley&Sons Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractTwo 30 dm3coastal seawater samples were collected in September 1983. One was acidified, homogenized and divided among 50 500‐cm3glass ampoules. The second was spiked with 612ng of mercury added as methylmercury chloride, acidified, homogenized and divided among 50 500‐cm3glass ampoules. All these operations were performed under a mercury‐free atmosphere. A single sample from each set was sent to each of 37 laboratories; 21 of them submitted their results of a ‘total’ mercury concentation determination. The consensus values and their confidence limits are 6.0 ± 1.6 and 24.2 ± 2.8 ng dm−3for the natural and the spiked samples respectively. Eleven laboratories reported reliable quantitative results (within ± 2SD) for the natural (unspiked) sample, and 12 for the spiked sample. In addition, ten laboratories give sets of results within ± 2SDof the consensus values. Storage for up to four months of methylmercury spiked samples with 1.4% nitric acid (0.3 mol dm−3) at room temperature is, alone, an unsuitable treatment for releasing mercury from its mon

ISSN:0268-2605    

DOI:10.1002/aoc.590040109

出版商:John Wiley&Sons Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractTributyltin (TBT) and its degradation products were measured in seawater samples in 1988 and 1989 at different locations of the French Mediterranean coast, including harbours, marinas and mariculture areas. Higher levels of TBT contamination were found in harbour (2–833 ng dm−3) and marina waters (18–736 ng dm−3) compared with mariculture areas (<2–111 ng dm−3). Geographical distribution of TBT degradation products showed that a TBT hot spot finally results in a diffuse contamination of dibutyltin (DBT) and monobutyltin (MBT), even far distant from

ISSN:0268-2605    

DOI:10.1002/aoc.590040110

出版商:John Wiley&Sons Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractTributyltin compounds have been successfully used for many years as wood preservatives, although their chemical nature in timber has not been fully elucidated. This study by119Sn and13C NMR spectroscopy has shown that, on impregnation intoPinus sylvestrissapwood, bis(tributyltin) oxide [(Bu3Sn)2O] is rapidly converted to tributyltin carboxylates (Bu3SnOCO·R) via reaction with components of the wood resin. It is further suggested that the formation of these species is a prerequisite for the known disproportionation reaction which occurs in (Bu3Sn)2O‐treated timb

ISSN:0268-2605    

DOI:10.1002/aoc.590040111

出版商:John Wiley&Sons Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractTriorganotin halides, oxides and sulphides can be dissolved in molten, mixed‐metal acetates atca140–160°C without decomposition; quenching provides glasses into which are encapsulated the organotin species. Halide/acetate and oxide/acetate, but not sulphide/acetate, exchanges occur in the melt. Only partial exchange was found for hindered trineophyl tin chloride [(PhCMe2CH2)3SnCl], in contrast to the complete exchanges observed for the butyl (Bu), phenyl (Ph) and cyclohexyl (Cy) analogues. Complete oxide/acetate exchange was found for (Bu3Sn)2O, partial exchange occurred for (Cy3Sn)2O, whilst no exchange resulted with bis(trineophyltin) oxide or (Ph3Sn)2O. Tin–tin bonds (e.g. as in Ph3SnSnPh3) and carbon–tin bonds (even the allyl–Sn bond in Bu3SnCH2CHCH2) are not affected. The acetate glasses dissolve in aqueous media with release of the organotin species and they have potential as slow‐release systems which is currently bein

ISSN:0268-2605    

DOI:10.1002/aoc.590040112

出版商:John Wiley&Sons Ltd.    

年代:1990

数据来源: WILEY