Zinc, and Mercury

Zinc and Mercury.—Photolysis of diphenylzinc in either CHC12 or CCl produces PhZnCl.292  

Galiullina, G. G. Petukhov, V. I. Khruleva, and Y. N. Krasnov, Zhur. obshchei Khim., 

Hg(CCl8)2 in the solid,293 solution, or gas phase.294 Similarly, Hg(OAc) CH-(COBufc)J undergoes photolysis of the Hg—C bond.295 

COaR radicals formed from PhHgC02Me, Hg(COaMe)2, and PhHgC02Et have been trapped by nitrones and 2,4,6-tri-t-butylnitrosobenzene.296 The carbyne species formed on irradiation of (71) reacts with Mn(CO)8Br to give (72).297 

Zinc and Mercury. - New methods for the preparation of reactive forms of zinc broaden the synthetic applications of this metal. The use of a Zn/Ag- graphite reagent, prepared from CgK and ZnC /AgOCOCHg, allows the Reformatsky reaction to be carried out efficiently at low 

Reagents i, Hg(OCOCF3)2, CH2Ct2,then NaCI/H20 ii,LiAIH  

Reformatsky reagents react with allylic halides or acetates in 

The application of dialkylzincs in the area of asymmetric synthesis continues to receive attention. Noyori and co-workers have made a survey of chiral 8-aminoalcohols capable of activating the addition of either Et2Zn or Me2Zn to aldehydes. The camphor-based 

Zinc and Mercury.- There has not been a great deal of activity in the organozinc area this year. Reformatsky reagents react with 0-silylated cyanohydrins to provide tetronic acids in good yields 

A new reducing agent, made up of a mixture of NaBH and ZnCl2 in 

Stereochemical control has developed as a major theme in solvo- 

Demercuration of ot-mercurocarboxylates (89) can be carried out selectively to give either of the diastereomeric B-hydroxy-esters 

Allenic ketones (92) undergo a clean cyclization in the presence of Hg(0C0Me)p in acetic acid to give 3 (211)-furanones (93) directly 

2 Zinc and Mercury.- [Nb(ZnCp)H2Cp23 and [Ta(ZnCp)2HCp have 

A range of mercury-transition metal bonded complexes have been subjected to X-ray structural analysis complexes with M-Hg-M links include CHg cis-RuMe(PMe )4 [Hg Pt(2,4,6-CgH2Cl3)(PPh-)2 2  

Bridging u-HgX units are present in CRh2(y-HgCl)(u-H) p-(PhO)2PNEtP- 

Physical studies of M-Hg (M Fe,Rh,Pt) complexes, Including reports of Hg n.m.r., are described. 

A central Tl atom in CTl Rug(yg-C) (CO.glj] links two Rug octa-hedra by edge-bridging two Ru-Ru bonds. 

The reaction of pentafluorophenylmagnesium chloride with aldehydes and ketones has been used to prepare pentafluorostyrenes via dehydration with PjOs of the intermediate alcohols. 2-Hydroxy-2-pentafluorophenyl- 

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Zinc and mercury are found in the Earth s crust as suifide ores, the most common of which are sphaierite (ZnS) and cinnabar (HgS). See the previous section for descriptions of the extraction and purification of these metais. 

Post-precipitation involves the deposition of a sparingly soluble impurity of similar properties to the precipitate on the surface of that precipitate after it has been formed. It is particularly a problem where similar materials are being separated on the basis of their different rates of precipitation, e.g. calcium and magnesium oxalates or zinc and mercury sulphides. Copreci-... 

Indirect electroreduction with Ni, Co, and Fe complexes has been well studied, and will be discussed first. Furthermore, the synthetic use of palladium, rhodium, and ruthenium complexes as mediators in the electroreduction of organic compounds are finding increasing apphcations. Metallic complexes derived from chromium, manganese, molybdenum, tungsten, and rhenium have also been used as mediators for special conversions. Recently, tin, zinc, and mercury... 

Although cadmium is not considered a transition element in some periodic tables, it is the central element of the triad with zinc and mercury. Zinc is just above it and mercury is below it in group 12 of the periodic table. Cadmiums chemical and physical properties are similar to its group 12 mates. Their electronegativity is very similar Zn = 1.6, Cd = 1.7, and Hg = 1.9. 

Raman spectral studies of solutions of metal nitrates in liquid ammonia show a coordination number of four for zinc and mercury, but six for cadmium. Dissolution of Znd2 and InCl3 in a 1 2 ratio in liquid HCN yields [Zn(NCH)6] [InCLJ2 with HCN coordination via nitrogen.137 A Raman study of the compounds [Cd(NH3)6]X2 (X = C1, Br or I) has been reported.138 Structural determinations of A2Zn(NH2)4 (A = Rb or K) reveal monomeric tetrahedral anions.139... 

The reaction of dithiooxamide and its tetramethyl and tetraethyl derivatives with zinc, cadmium and mercury halides leads to complexes of stoichiometry MLX2 (M = Zn, Cd or Hg X = C1, Br or I).900,9 1 M—S bonding is involved IR spectra show that the zinc and mercury complexes are four-coordinate, while the cadmium complexes are octahedral with halogen bridges. 

SWARTS REACTION. Fluorination of organic polyhalides with antimony trifluoride (or zinc and mercury fluorides) in the presence of a trace of a pentavalent antimony salt. 

H. L. Wells, and H. Klinger s basic nitrates of lead, cadmium, zinc, and mercury were shown by G. Watson to fall in line with this hypothesis but F. Meissner could not support it, and F. W. Kuster and R. Kremann showed that the f.p. curve of binary mixtures of nitric acid and water invalidates H. Erdmann s conclusions— vide infra. 

Table 5 shows the HMBC of 7 MSW landfill leachates for copper, zinc and mercury. These data indicate that the MSW landfill leachate metal binding capacity was relatively high and was site-specific. HMBCs for the MSW leachate samples ranged from of 2.9 to 114.9, 4.9 to 45.2, and 3.6 to 100.8 for HMBC-Cu+2, HMBC-Zn+2, and HMBC-Hg+2, respectively. Comparatively, much lower HMBC values were obtained for other environmental samples, such as lake water (Lake Alice and Lake Beverly) and a wastewater treatment plant effluent (data not shown). 

The trans-planar structures, which are distorted as a result of the influence of R -substituent, exist mostly in complexes 868 (X = 0, M = Ni, Cu) with coordination unit MN202 [132-135,151], Such structures are practically not observed in the case of a studied ICC of palladium, which possesses the strongest planarizing action [132-135,152,153], Formation of tetrahedral o-hydroxyazomethinic ICC is characteristic exclusively for beryllium and preferably for cobalt, zinc, and mercury [132-135],... 

Complexes of several S-donor ligands have also been reported. The reaction of dithio-oxamide and its tetramethyl and tetraethyl derivatives with zinc, cadmium, and mercury halides leads to complexes of stoicheiometry MLX2 (M = Zn, Cd, or Hg X = Cl, Br, or I).64,65 M—S bonding is involved i.r. spectra show that the zinc and mercury complexes are four-co-ordinate, while the cadmium complexes are octahedral with halogen bridges. The complexes [ML3][C104]2 have also been prepared and do not contain co-ordinated perchlorate. The complexes ZnL (H2L = dithio-oxamide, NiV-dimethyl- and IVA -dicyclohexyl-dithio-oxamide) have been isolated,66 and consist of linear chains containing four-co-ordinate zinc. 

Sulfides, Antimonides, Selenides, and Tellurides are minerals in which sulfur, antimony, selenium, or tellurium combine with one or more metals, or with one metal and one semi-metal. Some sulfide minerals are valuable sources of such elements as copper, silver, zinc, and mercury. 

Both zinc and mercury have been known for hundreds of years, despite having relatively low abundance, because they are easily extracted from the minerals in which they occur. 

Seymour, A.H. and Nelson, V.A. Biological half-lives for zinc and mercury in the Pacific oyster, Crassostrea gigas, p. 849-856, 2 Proc. Third Nat l. Symp. on Radioecology, Oak Ridge, Tennessee, May 10-12, 1971. CONF-710501, 1972. 

The Clenimensen reduction uses zinc and mercury in the presence of strong acid. 

Group lib of the periodic table includes two very important ele ments, zinc and mercury, and one element, cadmium, which has four d rather limited use. 

While the zinc and mercury derivatives are stable in benzene-dj solution for at least 3 days, the cadmium derivative is much less stable. The Si NMR shifts for these compounds move to lower field on descending the... 

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