Copper bronze powder

Interestingly, the Fischer indole synthesis does not easily proceed from acetaldehyde to afford indole. Usually, indole-2-carboxylic acid is prepared from phenylhydrazine with a pyruvate ester followed by hydrolysis. Traditional methods for decarboxylation of indole-2-carboxylic acid to form indole are not environmentally benign. They include pyrolysis or heating with copper-bronze powder, copper(I) chloride, copper chromite, copper acetate or copper(II) oxide, in for example, heat-transfer oils, glycerol, quinoline or 2-benzylpyridine. Decomposition of the product during lengthy thermolysis or purification affects the yields. 

In a 100-ml. pressure vessel (Note 1) are placed 14.0 g. (0.050 mole) of 3-bromopyrene (Note 2), 0.5 g. of copper bronze powder (Note 3), 1.5 g. of cuprous oxide (Note 4), and 60 ml. of 10% aqueous sodium hydroxide (Note 5). The vessel is sealed, heated rapidly with shaking to 275-280°, and maintained at this temperature for 3 hours. The vessel is allowed to cool and is opened, and the contents are poured into a 500-ml. beaker containing 200 ml. of water (Note 6). The mixture is filtered, and the filter cake is washed with water until the washings become neutral to pH paper. The combined filtrate and washings, which show a blue fluorescence, are made acid to Congo red paper with 20% aqueous sulfuric acid. The precipitate is collected by filtration, washed free of acid with water, and dried in an oven at 100° to give ca. 9 g. of a gray solid. 

Problem 18.70 What compound results from treating the diazonium salt of p-toluidine with copper bronze powder ... 

SYNS AT.T.BRT natural COPPER ANAC 110 ARWOOD COPPER BRONZE POWDER CDA 101 CDA 102 CDA 110 CDA 122 C.I. 77400 C.I. PIGMENT METAL 2 COPPER-AIRBORNE COPPER BRONZE COPPER-MILLED COPPER SLAG-... 

SYNONYMS allbri natural copper, bronze powder, copper bronze... 

SYNONYMS arwood copper, bronze powder, C.I. 77400, copper bronze, copper metal dusts, copper metal mists, raney copper. 

Both matchhead and striker formulas contain an acid-neutralizing but insoluble salt such as calcium carbonate (whiting, ground limestone). This aborts any tendency to destructive oxidation of the sulfur in the head or of the red phosphorus in the striker. The latter process can be greatly accelerated by catalytic influence of certain heavy metals, especially copper. Since copper-bronze powders are well liked as decorative components of the artwork on the cover of book matches, improper formulation of the striking strip may lead to complete destruc-... 

Synonyms Arwood copper Bronze powder Cl 77400 Copper bronze Copper-milled Gold bronze Kafar copper Pigment metal 2 Raney copper... 

The synthesis of SFs-substituted phenothiazine was disclosed in a patent from Smith, Kline French Laboratories (63USP3107242). 3-SFs-Acetanilide (120), prepared by acetylation of d-SFs-aniline (39) with acetic anhydride, was first condensed with bromobenzene under basic conditions, in the presence of Cul and copper-bronze powder, and after add hydrolysis provided 3-SFs-diphenylamine (121). This product was then fused with sulfur in the presence of a catalytic amount of iodine to give 2-SFs-phenothiazine (122) in unreported yield (Scheme 34). 

Copper powder n. Metallic copper and copper bronze powders have some apphca-tion in anti-fouling paints, and in special... 

Ethyl-l-pentyn-3-ol added dropwise with stirring and ice-cooling to a mixture of excess coned. HCl, 0.5 mole of calcium chloride, 0.4 mole of CuCl, and some copper bronze powder, stirring continued 1 hr. at 0-5° 3-chloro-3-ethyl-l-pentyne. Y 83%.— This procedure gives higher yields and purer products than previous methods. F. e. s. G. F. Hennion and A. P. Boisselle, J. Org. Chem. 26, 725 (1961). 

Copper Powder n Metallic copper and copper bronze powders have some application in anti-fouling paints, and in special primers. Copper bronzes of various colors are produced according to the amount of alloy metal present. In producing finishes from copper and copper bronze powders, great care in formulation is necessary, for these pigments are apt to cause inhibition of drying, discoloration of media, and gelation. 

The oxygen in the free hydroxyl groups of diesters of phosphoric acid has been specifically analyzed by Dostrovsky and Halmann (1956) by condensation with tolyl carbodiimide. The substituted urea formed is separated and purified. On heating a sample (30 mg.) to 320°C. with copper bronze powder (1 mg.), carbon dioxide is evolved which contains the oxygen of the free hydroxyl groups of the phosphate. This method is fully described by Halmann (1959) and can presumably be used with monoesters of phosphoric acid and with various phosphonic and sulfonic acids. (See also Pinchas et al., 1962.)... 

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