Cadmium diphenyl

Cadmium diphenyl, CdPhgA niay be obtained by heating metallic cadmium and mercury diphenyl in an atmosphere of hydrogen. It is stable in the dry state, but becomes discoloured w hen kept in a vacuum desiccator for an hour. When air is passed through its benzene solution several colour changes take place, and a reddish-brown body is finally precipitated. With water the brown solution is decolorised and cadmium hydroxide preci]>itated. Cadmium diphenyl quickly decolorises iodine solution, and the cadmium may be replaced by mercury or zinc with formation of mercury and zinc diphenyl. 

Cadniiu.m, In hydrogen atmosphere. Cadmium diphenyl. Ililpert and (iriittner, he. rjl. 

Propiophenone. Prepare a solution of diphenyl-cadmium in 110 ml. of dry benzene using 4 9 g. of magnesium, 32 4 g. of bromobenzene and 19 5 g. of anhydrous cadmium chloride. Cool the solution to 10°, and add during 3 minutes a solution of 14 -8 g. of propionyl chloride (b.p. 78-79°) in 30 ml. of dry benzene use external coohng with an ice bath to prevent the temperature from rising above 40°. Stir the mixture for 2 hours at 25-35°. Work up the product as detailed above except that 6 per cent, sodium carbonate solution should replace the saturated sodium bicarbonate solution. The yield of propiophenone, b.p. 100-102°/16 mm., is 17 6 g. 

CgHsljCd + 2aCOCH2CH,-Diphenyl-cadmium Proplonyl chloride... 

For this purpose, the WEEE Directive has been complemented with an additional directive that limits the use of certain pollutants in these products. The EC Directive 2002/95/EC on the Restriction of the use of certain Hazardous Substances in electrical and electronic equipment (RoHS Directive) ([7], recast 2011 [9]) restricts the use of the six harmful substances/substance families lead, mercury, hexavalent chromium, polybrominated biphenyls (PBB), and polybrominated diphenyl ethers (PBDE) to 0.1% and cadmium to 0.01% w/w per homogenous material in equipment and components, but with several exemptions for a wide range of applications (Annex III and IV). 

EPA (2000c) Environmental Protection Agency. Integrated risk information system (IRIS) data for brominated diphenyl ethers. Available at http //www.epa.gov/iris EPA (2005a) http //www.epa.gov/OGWDW/dwh/t-ioc/cadmium.html... 

N 4 68%, mp 86°. This ester was prepd by reacting diphenyl cadmium and 4-nitrophthalic anhydride to give the acid which was esterified Ref J. Tirouflet, BuiISciSocBretagne Spec No 26, 80-88(1951) CA47, 8694(1953)... 

The reaction is illustrated by the formation of propiophenone from diphenyl-cadmium and propanoyl chloride (Expt 6.126). Better yields are obtained by carrying out the synthesis in this manner rather than attempting the alternative combination of diethylcadmium with benzoyl chloride. Alternatively an alkyl-lithium cuprate could be used with an aromatic acid chloride (p. 616). 

The best listing of fungicides that we know of is published annually by the Meister Publishing Company of Willoughby, Ohio in their Farm Chemicals Handbook. They list the following compounds or types of compounds as officially "registered" for use on plants in the United States allyl alcohol, ammonium isobutyrate, antibiotics, benzimidazole types, carbofuran, cadmiums, captan types, coppers, carboxin, dehydroacetic acid, Dexon (sodium [4-(dime thy lamino) phenyl diazo sulfonate), diphenyl,... 

The reaction of diphenyl tellurium dichloride with phenyl lithium yielded tetraphenyl tellurium1. Bis[trifluoromethyl] tellurium dichloride and bis[trifluoromethyl] cadmium reacted to produce tetrakis[trifiuoromethyl tellurium2. 

CsoHjjFigNjPj, 3,11,15,19,22,26-Hexaazatri-cyclolll.7.7.I - )octacosa-l,5,7,9(28), 12,14,19,21,26-nonaene, 3,11-dibenzyl-14,20-dimethyl-2,12-diphenyl-, tris hexafluorophosphate(l —)], 27 278 CdClj, Cadmium dichloride, 28 322 CeCljLiOjSigCjflHjg, Cerium, bis[ii -l,3-bis(trimethylsilyl)cyclopentadienyl]di-p-chloro-bis(tetrahydrofuran)-lithium-, 27 170... 

The European Union has taken the lead in restricting the use of some hazardous materials in the manufacture of electrical and electronic hardware. The program, referred to as Restriction of Hazardous Substances (RoHS), applies to all electrical and electronic products produced in Europe and products imported from other countries, thus has very broad application. The regulations put into force on July 1, 2006, apply to lead, cadmium, mercury, hexavalent chromium (Cr ), poly-brominated biphenyl (PBB), and polybrominated diphenyl ether (PBDE). The RoHS guideline document specifies 0.1% or 1,000 ppm as the maximum amount permitted for lead, mercury, Cr" " , PBB, and PBDE and 0.01% or 100 ppm for cadmium. The document also describes guidelines for sample preparation and analyses of the restricted materials. 

There is also the EU Restriction of the Use of Certain Hazardous Substance Directive (RoHS) in electrical and electronic equipment which bans new electrical and electronic equipment with more than agreed levels of cadmium, hexavalent chromium, lead, mercury, polybrominated biphenyls (PBB) and polybrominated diphenyl ether (PBDE) flame retardants, in the EU. The RoHS Directive and the UK-RoHS regulations came into force on 1st July 2006 [9]. To prevent the generation of hazardous waste, the Directive 2002/95/EC requires the substitution of all heavy metals (cadmimn, hexavalent chromium, lead and mercury) and brominated flame-retardants (PBB or PBDE) in new electrical and electronic equipment sold as of 1st July 2006 [10]. 

---