Palladium salts sensitizers

Palladium(V) complexes, 5, 1100 Palladium compounds photothermography, 6, 118 Palladium dichloride solid state oligomerization, 1, 187 Palladium(II) salts sensitizers... 

Miscellaneous. Reduction of a palladium salt by CO is the basis of a visual test for ambient carbon monoxide (227). Palladium compounds are used as photographic sensitizers (228). The low dimensional mixed valence compound Csq 3[Pd(S2C2(CN)2)] 0.5H2O behaves as a semimetal at room temperature (229). Palladium compounds isostructural with potent platinum antitumor compounds have poor antitumor activity (230). 

The results in the diazomethane reactions involving zinc(II) chloride catalysis have been explained by invoking a carbenoid intermediate. The properties of such a species will, of course, be sensitive to the nature of the metal and this might explain the different regioselectivity observed when diphenyldiazomethane is decomposed with rhodium and palladium salts in the presence of 5-methylenebicyclo[2.2.1]hept-2-ene (9). With rhodium(II) acetate as catalyst the exocyclic double bond is attacked exclusively, whereas palladium(II) chloride catalysis directs cyclopropanation to the endocyclic double bond. ... 

Not much is known about the normal azide Pd(N3)2 except that it is a brown, water-insoluble solid which is very sensitive to heat, friction, and impact [139,158]. It is precipitated when solutions of palladium salts and azide are combined, e.g., 0.1 M sodium azide and 0.01 M palladium perchlorate are mixed in molar ratios, but the precipitate cannot be dried without exploding [166]. This azide is occasionally obtained as an undesired intermediate to the complex paDadium azides. 

The use of other sensitive elements can eliminate completely the silver from the Imaging process. This 1s the case for imaging with titanium dioxide and nucleatlon with palladium salts. 

A reverse cross-coupling reactions mediated by palladium was used to develop a colorimetric sensitive chemodosimeter for the detection of trace palladium (II) salts [93]. The decolorization of 4 is produced by a nucleophilic attack of ethanethiol in basic DMSO solutions. Palladium detection is done via thiol scavenging from the 4-ethanethiol complex leading to a color turn-on of the parent squaraine. Naked-eye detection of Pd(NC>3)2 is as sensitive as 0.5 ppm in solution, and the instrument-based detection can go as low as 0.1 ppm. 

Polymeric alkene ozonides are shock-sensitive that of trans -2-butene exploded when exposed to friction in a ground glass joint. The use of GLC to analyse crude ozonisation products is questionable because of the heat-sensitivity of some constituents [4], Ozonides are decomposed, sometimes explosively, by finely divided palladium, platinum or silver, or by iron(II) salts [5]. Individually indexed compounds are ... 

The arylamine 780b required for the total synthesis of carbazomycin B (261) was obtained by catalytic hydrogenation, using 10% palladium on activated carbon, of the nitroaryl derivative 784 which was obtained in six steps and 33% overall yield starting from 2,3-dimethylphenol 781 (see Scheme 5.85). Electrophilic substitution of the arylamine 780b with the iron-complex salt 602 provided the iron complex 787 in quantitative yield. The direct, one-pot transformation of the iron complex 787 to carbazomycin B 261 by an iron-mediated arylamine cyclization was unsuccessful, probably because the unprotected hydroxyarylamine moiety is too sensitive towards the oxidizing reaction conditions. However, the corresponding 0-acetyl derivative... 

Between 1980 and about 2000 most of the studies on the electrodeposition in ionic liquids were performed in the first generation of ionic liquids, formerly called room-temperature molten salts or ambient temperature molten salts . These liquids are comparatively easy to synthesize from AICI3 and organic halides such as Tethyl-3-methylimidazolium chloride. Aluminum can be quite easily be electrode-posited in these liquids as well as many relatively noble elements such as silver, copper, palladium and others. Furthermore, technically important alloys such as Al-Mg, Al-Cr and others can be made by electrochemical means. The major disadvantage of these liquids is their extreme sensitivity to moisture which requires handling under a controlled inert gas atmosphere. Furthermore, A1 is relatively noble so that silicon, tantalum, lithium and other reactive elements cannot be deposited without A1 codeposition. Section 4.1 gives an introduction to electrodeposition in these first generation ionic liquids. 

Palladium. Flame AAS analysis of Pd is described in P CAM 173 however, it would probably be preferred to use graphite furnace atomization as in S-191 Pt, soluble salts. An oxidizing air-acetylene flame is used for Pd AAS to minimize interferences from Al, Co, Ni, Pt, as well as Rh and Ru. These interferences may be minimized by complexation of Pd as the bis-pyridine-dithiocyanate (13) and extraction into hexone (3). Interferences may be minimized by the addition of 1000 ppm La. The 244.8 and 247.6 nm lines have equal sensitivity however, the 247.6 nm line is generally preferred ( 3). No Federal standard exists for Pd however, in analogy to Ni and Pt, Pd should be treated with caution. 

Palladium-catalyzed methylene transfer from diazomethane has proved effective for the cyclopropanation of 1-alkenylboronic acid esters allylic alcohols and amines 1-oxy-l,3-butadienes and allenes " Readily accessible iron complex (CO)2FeCH2S Me2 BF4 35 undergoes direct reaction with a range of alkenes to give cyclopropanes (equation 67) The salt is sensitive to steric effects and the reaction proceeds... 

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