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Metal acetylides cuprous acetylide

A lab method of prepn is described in Ref 6. Its toxicology, fire hazard, storage and handling are discussed in Ref 7. It was claimed (Ref 3) that the ignition sensitivity life of igniter compds contg cuprous acery-lide(or other metallic acetylides) is improved by the addition of small amounts of abietic acid... [Pg.3]

Heavy metal acetylides, particularly cuprous acetylide (CuC CH), catalyze the addition of acetylene (HC=CH) to aldehydes (RCH=0). [Pg.605]

Alkynylmagnesium halides are less basic than the alkali metal acetylides and therefore can be applied to sensitive alkylating agents. In contrast to the alkali metal acetylides they do not react with saturated primary halides. On the other hand, they do react with allylic, propargylic and benzylic halides, but only in the presence of cuprous chloride catalysts. They also react with a-haloethers (e.g. equation 136)" . [Pg.278]

D) Formation of Metallic Acetylides. Pass acetylene gas for one minute into 5 ml of each of the solutions of ammoniacal silver nitrate and ammoniacal cuprous chloride, prepared according to directions given below. Note the character of the precipitate. Disconnect the flask, and dispose of the material in the flask, according to directions given by the instructor. [Pg.119]

Although stoichiometric ethynylation of carbonyl compounds with metal acetylides was known as eady as 1899 (9), Reppe s contribution was the development of catalytic ethynylation. Heavy metal acetylides, particulady cuprous acetylide, were found to catalyze the addition of acetylene to aldehydes. Although ethynylation of many aldehydes has been described (10), only formaldehyde has been catalytically ethynylated on a commercial scale. Copper acetylide is not effective as catalyst for ethynylation of ketones. For these, and for higher aldehydes, alkaline promoters have been used. [Pg.103]

Separation of acetylene from the monomer by scrubbing with ammoniacal cuprous chloride (CAUTION This procedure may lead to the formation of metal acetylides among the reaction products. Acetylides of heavy metals are said to be explosive, especially when dry. Partially dried acetylides may present similar hazards) ... [Pg.333]

Metallic Derivatives, (a) Cuprous Acetylide. CujCg. Prepare an ammoniacal solution of cuprous chloride by first adding dilute ammonia to 2-3 ml. of dilute copper sulphate solution until the initial precipitate just redissolves and a clear deep-blue solution is obtained now add an aqueous solution of hydroxylamine hydrochloride drop by drop with shaking until the solution becomes first green and then completely colourless, the cupric salt being thus reduced to the cuprous derivative. [Pg.87]

The heavy metal salts of acetylene have the properties of primary explosives, but only cuprous acetylide was found to be satisfactory for practical use. [Pg.227]

C6HBC C.C C.C C.C C.C6H5 mw 250.28, yel ndls, mp li5—16°(browning), stable at RT for 13 months in the dark when placed on a hot metallic place it. decompd explosively with much soot. It shows no color reaction with sulfuric acid is more sol than tolan Sc (C6H.5C C)3 in polar solvs such as MeOH, ale Sc acetone. It was prepd by oxidative coupling of cuprous acetylide, C6HB.C C.C C.Cu, with CuCl2 (Refs)... [Pg.374]

The discovery of acetylene in 1836(or 1837) is attributed to Edmond Davy, but it was not until I860 that Berthelot definitely identified and named it(Ref 9, p 101 Ref 16, p 469). The compd obtained by Berthelot from cuprous acetylide was not pure because it contained some vinyl chloride. Acetylene was not produced commercially until Ca carbide was produced in the lab in 1899 by Morehead Willson, by heating a mixt of lime and coke in an electric furnace. They expected to prepare metallic calcium... [Pg.59]

Only one of the acetylides(cuprous acetylide) has found application in industry as an ingredient of electric detonators. Some acetylides, as for instance, that of silver, arc probably suitable for use in primers and detonators. They also may be incorporated in LA-based compositions for expl rivets in order to reduce their ignition point(Ref 6) According to Sax(Ref 6) the toxicity of acetylides is unknown, but their expln hazards are considered to be the same as those of fulminates and azides. The acetylides must be handled with extreme care and In storage they must be kept cool and wet. Metal powders, such as finely divided Cu or Ag, should be excluded. Shipping regulations are the same as for other primary and initiating explosives Refs l)Beil 1,238-40,(104 6),[217-20] ... [Pg.70]

One of the characteristic features of the metal-bis-acetylide complexes in chemical reactions is that they undergo a ligand exchange reaction with metal dihalides in amines in the presence of a cuprous halide catalyst to produce a monoalkynyl-metal-monohalide complex (Eq. IS) which results from selective cleavage of the metal-carbon bond weakened by the /ram-alkynyl group in the bis-acetylide... [Pg.167]

The reactions of acetylene which have been mentioned are analogous to those of the unsaturated hydrocarbons containing a double bond. Acetylene and other compounds which contain a carbon atom in combination with hydrogen and joined to a second atom in the manner which is represented by a triple bond, that is, those containing the group H —C =, show characteristic properties which serve to distinguish them from other substances. Such compounds are converted into metallic derivatives when they are treated with an ammoniacal solution of cuprous chloride or of silver chloride. If acetylene is passed into a solution of cuprous chloride in ammonia, a red precipitate is formed which has the composition C2CU2. This compound, which is a carbide of copper, is usually called copper acetylide. It explodes, when dry, if it is struck or is heated to 100°-120°. When treated with hydrochloric acid or with a solution of potassium cyanide, acetylene is formed. [Pg.65]


See other pages where Metal acetylides cuprous acetylide is mentioned: [Pg.75]    [Pg.148]    [Pg.197]    [Pg.70]    [Pg.280]    [Pg.520]    [Pg.366]    [Pg.477]    [Pg.5]    [Pg.8]    [Pg.163]    [Pg.164]    [Pg.109]    [Pg.163]    [Pg.164]    [Pg.70]    [Pg.653]    [Pg.424]    [Pg.70]    [Pg.392]    [Pg.315]    [Pg.684]    [Pg.5]    [Pg.214]   
See also in sourсe #XX -- [ Pg.593 ]




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Acetylide

Acetylides

Acetylides cuprous acetylide

Cuprous

Cuprous acetylide

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