Zinc copper acetate

Valentinite, see Antimony(III) oxide Verdigris, see Copper acetate hydrate Vermillion, see Mercury(II) sulflde Villiaumite, see Sodium fluoride Vitamin B3, see Calcium (+)pantothenate Washing soda, see Sodium carbonate 10-water Whitlockite, see Calcium phosphate Willemite, see Zinc silicate(4—)... 

In similar work, CF3CCI2CO2CH3 yields methyl a-trifluoromethyl-a,(i-un-saturated carboxylates when reacted with a zinc-copper couple, aldehydes, and acetic anhydride [67] (equation 55). This methodology gives (Z)-a-fluoro-a- -un-saturated carboxylates from the reaction of carbonyl compounds with CFCI2CO2CH3 and zinc and acetic anhydride [6 ]. 

Mercury and silver have long been known to have antibacterial properties and preparations of these metals were among the earliest used antiseptics, but have been replaced by less toxic compounds. Other metals such as zinc, copper, aluminium and tin have weak antibacterial properties but are used in medicine for other functions, e.g. aluminium acetate and zinc sulphate are employed as astringents. 

Several techniques have been used to activate the zinc metal and improve yields. For example, pretreatment of zinc dust with a solution of copper acetate gives a more reactive zinc-copper couple.168 Exposure to trimethylsilyl chloride also activates the zinc.169 Wilkinson s catalyst, RhCl(PPh3)3 catalyzes formation of Reformatsky reagents from diethylzinc, and reaction occurs under very mild conditions.170... 

Note. The zinc (0.2 mm. in thickness) was converted to a zinc-copper couple by adding to it a dilute aqueous solution of copper sulfate. We took care to maintain the reaction mixture below 15° when the acetic acid was added. 

Divalent chromium salts show very strong reducing properties. They are prepared by reduction of chromium(III) compounds with zinc [187] or a zinc-copper couple and form dark blue solutions extremely sensitive to air. Most frequently used salts are chromous chloride [7SS], chromous sulfate [189], and less often chromous acetate. Reductions of organic compounds are carried out in homogeneous solutions in aqueous methanol [190], acetone [191], acetic acid [192], dimethylformamide [193] or tetrahydrofuran [194] (Procedure 37, p. 214). 

Reduction of a,/3-unsaturated to saturated ketones was further achieved by electrolysis in a neutral medium using copper or lead cathodes (yields 55-75%) [766], with lithium in propylamine (yields 40-65%) [876], with potassium-graphite clathrate CgK (yields 57-85%) [807], and with zinc in acetic acid (yield 87%) [688]. Reduction with amalgamated zinc in hydrochloric acid (Clemmensen reduction) usually reduces both functions [877]. 

Under conventional dechlorination conditions (20 equiv of zinc dust, acetic acid, 25°C or 50°C) the reduction of 4,4-dichlorocyclobutenones affords complex mixtures of products which include the desired cyclobutenones as well as significant amounts of partially reduced byproducts. He have found that the desired transformation can be accomplished cleanly provided that the reduction is carried out at room temperature in alcoholic solvents (preferably ethanol) in the presence of 5 equiv each of acetic acid and a tertiary amine (preferably tetramethylethylenediamine). Zinc dust has proven to be somewhat superior to zinc-copper couple for this reduction. The desired cyclobutenones are obtained in somewhat higher yield using this procedure as compared to the related conditions reported by Dreiding [Zn(Cu), 4 1 AcOH-pyridine, 50-60 C] for the same transformation. ... 

Previously published methods for the synthesis of dimethylzinc, a useful alkylating agent, include the reaction of dimethylmercury with metallic zinc,1 the reaction of a zinc-copper couple with methyl iodide,2 and the Grignard method.3 The reaction of trimethylaluminum with zinc(II) halides or alkoxides can be used,4 but it is more convenient to use zinc(ll) acetate, which is very readily obtained by dehydrating the commercial dihydrate with boiling acetic anhydride or by the reaction5 ... 

Ishihara and coworkers have reported that the reaction of 2-[(trimethylsilyl)methyl]-3-chloro-3,3-difluoropropene couples regioselectively with a variety of carbonyl compounds in the presence of zinc-copper chloride or silver acetate to give 2,2-difluoro-3-(trimethylsilyl)methyl-3-buten-l-ol derivatives (equation 87)81. Note again that the difluo-roallyl zinc species generated in situ reacts exclusively on the difluoromethylene terminus. 

Compound Name Copper Acetate Dimethylacetamide Ethyl Acetate Isobutyl Acetate Isopropyl Acetate Methyl Acetate Nickel Acetate n-Propyl Acetate Sec-Butyl Acetate Zinc Acetate Acetaldehyde Acetic Anhydride Ethyl Acetate Ethyl Acetate Ethyl Acetoacetate Ethyl Acetoacetate Acetone... 

In addition to the procedures summarized in Table 6, modifications of the zinc dehalogenation have appeared. For example, copper-activated zinc in the presence of ammonium chloride with methanol as solvent apparently gives better yields and, in some cases, is the method of choice.90,91 124 An example of this procedure is the reductive dechlorination of 8,8-dichloro- l-phenylbicyclo[4.2.0]octan-7-one, with zinc in acetic acid, to give l-phenylbicyclo[4.2.0]octan-7-one (7) in 30% yield. The use of zinc and ammonium chloride in methanol gave 7 in 70% yield.124 However, no general trend can be seen. Another variation is to replace ammonium chloride with hydroxylamine hydrochloride.116... 

Subtle variations in the structures of acyl groups attached to nucleosides have been made in order to allow such groups to be removed under mild or special conditions that do not affect other acyl groups. The (2,2,2-tribromoethoxy)carbonyl group is susceptible to non-hy-drolytic removal by using a zinc-copper couple in acetic acid thus, 3 -0-acetyl-5 -0-(2,2,2-tribromoethoxycarbonyl)- and 5 -0-acetyl-3 -0-(2,2,2-tribromoethoxycarbonyl)-thymidine gave170 3 -0-acetyl- and 5 -O-acetyl-thymidine in a yield of 75 and 60%, respectively. 

A large variety of aromatic amines react with isatins to give anils (132).169,232,269,305,312,411 413 The imine from isatin and o-hydroxy-aniline forms complexes with copper acetate and zinc iodide.413 Reaction of these anils (132) with phenylhydrazine gives the isatin-3-phenylhydrazone.411 The imine 132 (R = 5-Me, R = H, Ar = p-tolyl)... 

Zinc-Copper(II) acetate, 346 Zinc-copper couple, 220, 348... 

A powder which burns with a green flame is obtained by the addition of nitrate of baryta to chlorate of potash, nitrate of potash, acetate of copper. A white flame is made by the addition of sulfide of antimony, sulfide of arsenic, camphor. Red by the mixture of lampblack, coal, bone ash, mineral oxide of iron, nitrate of strontia, pumice stone, mica, oxide of cobalt. Blue with ivory, bismuth, alum, zinc, copper sulfate purified of its sea water [sic]. Yellow by amber, carbonate of soda, sulfate of soda, cinnabar. It is necessary in order to make the colors come out well to animate the combustion by adding chlorate of potash.15... 

Like zinc, copper and its compounds have been used since ancient times, with copper dust, acetate, sulfate and carbonate reported in Egyptian and Hindu prescriptions, and also used by Hippocrates and Galen. Copper arsenite was used in 1892 for anemia and debility. Copper sulfate was recommended to strengthen man, to stimulate the heart and blood vessels, to increase deposition of fat and to treat anemia. The adult requirement is 1.25 mg Cud-1, about one third of which is absorbed. TPN should be supplemented with 0.5—1.5 mg d-1 (adults) and 20 gg (kg weight)-1 d-1 (children). 

Inorganic arsenicals find limited use as pesticides. Examples include arsenious oxide in cattle dips, zinc arsenite as a wood preservative, and calcium and lead arsenates and Paris green (double salt of copper arsenite and copper acetate) as insecticides30. ... 

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