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Potassium Hydrogen Acetylide

Potassium Hydrogen Acetylide A79-L Potassium-Iron Alum A156-R Potassium-5-nitraminotetrazoIe A260-L... [Pg.689]

Monopotossium Acetylide or Potassium Hydrogen Acetyl do (Ethynylporassium),... [Pg.79]

The reaction of monodeprotonated [ C2]acetylene with carbonyl compounds has been exploited as a means of extension of the carbon chain of various terpenes and steroids by two [ " C]carbon atoms. In the simplest case, reaction of potassium [ C2]acetylide with steroid ketone 1 and subsequent acid catalyzed cleavage of the enol ether protecting group gave 17a-[ C2]ethynyltestosterone (2). The sequential addition of deprotonated [ C2]acetylene to carbonyl compounds opens access to symmetrical or unsymmetrical [2,3- C2]alkyn-l,4-diols is exemplified in the synthesis of all-tran -/3-[15,15 - C2]-carotene ([ C2]provitamin A). Thus, treatment of lithium [ C2]acetylide with terpene aldehyde 2 followed by double deprotonation of the resultant alkynol 4 and reaction with a second equivalent of 3 provided alkyne-l,4-diol 5 the requisite key intermediate. Subsequent acid-catalyzed dehydration of 5 followed by Lindlar s catalyst-mediated partial hydrogenation and photoisomerization afforded the final product". ... [Pg.442]

Hydrogen chloride Acetic anhydride, aluminum, 2-aminoethanol, ammonia, chlorosulfonic acid, ethylenediamine, fluorine, metal acetylides and carbides, oleum, perchloric acid, potassium permanganate, sodium, sulfuric acid... [Pg.1208]

The substance is stable at ordinary temperatures and up to 100°C. Like cupric acetylide it decomposes on being heated in hydrochloric acid (Berthelot [102], Sabaneyev [107]). A solution of potassium cyanide also causes decomposition with the loss of acetylene. Makowka [108] showed that aldehyde-like compounds are formed from cuprous acetylide on reaction with a 30% solution of hydrogen peroxide. [Pg.228]

SAFETY PROFILE A highly corrosive irritant to the eyes, skin, and mucous membranes. Mildly toxic by inhalation, Explosive reaction with alcohols + hydrogen cyanide, potassium permanganate, sodium (with aqueous HCl), tetraselenium tetranitride. Ignition on contact with aluminum-titanium alloys (with HCl vapor), fluorine, hexa-lithium disilicide, metal acetylides or carbides (e.g., cesium acetylide, rubidium ace-tylide). Violent reaction with 1,1-difluoro-ethylene. Vigorous reaction with aluminum, chlorine + dinitroanilines (evolves gas). Potentially dangerous reaction with sulfuric acid releases HCl gas. Adsorption of the acid onto silicon dioxide is exothermic. See also HYDROGEN CHLORIDE (AEROSOL) and HYDROCHLORIC ACID. [Pg.743]

It is sometimes necessary to protect active sites of acetylenic compounds to achieve the desired reactions. Acetylenic compounds that have an active hydrogen tend to react with heavy-metal salts to form explosive metal acetylides. However, when treated with potassium mercuric tetraiodide or mercuric acetate in organic amines, monosubstituted terminal ethynyl compounds give stable crystalline mercuric salts. These mercuric salts can be purified by recrystallization in organic solvents and used for identification. They can be further converted to lithium acetylides, which are useful tools for chemical synthesis [Eq. (62) 156]. [Pg.661]

COPPER (7440-50-8) Cu The powder forms the friction-, heat-, or shock-sensitive explosive detonator, copper acetylide, with acetylene gas acetylenic compounds and ethylene oxides. The powder forms explosive materials with azides (e.g., sodium azide forms potentially explosive copper azide). Finely divided material forms friction-, heat-, or shock-sensitive explosive with powdered divided bromates, chlorates, and iodates of barimn, calcimn, magnesium, potassium, sodium, or zinc. Violent reaction, possibly explosive, when finely dispersed powder comes in contact with strong oxidizers ammonium nitrate alkynes, bromine vapor, calcium carbide, chlorine, ethylene oxide, hydrazine mononitrate, hydrogen peroxide, hydrogen sulfide, finely divided bromates, iodine, lead azide, potassium peroxide, sodium peroxide (incandescence), sulfuric acid. Incompatible with acids, anhydrous ammonia chemically active metals such as potassium, sodium, magnesium, and zinc, zirconium, strong bases. [Pg.278]


See other pages where Potassium Hydrogen Acetylide is mentioned: [Pg.1003]    [Pg.1477]    [Pg.5]    [Pg.33]    [Pg.411]    [Pg.95]    [Pg.210]    [Pg.670]    [Pg.738]    [Pg.776]    [Pg.827]    [Pg.1000]    [Pg.1084]    [Pg.1118]    [Pg.1265]    [Pg.978]    [Pg.394]    [Pg.1388]    [Pg.130]    [Pg.21]    [Pg.45]    [Pg.72]    [Pg.109]    [Pg.200]    [Pg.202]    [Pg.232]    [Pg.245]    [Pg.266]    [Pg.280]    [Pg.285]    [Pg.286]    [Pg.323]    [Pg.405]    [Pg.496]   
See also in sourсe #XX -- [ Pg.7 ]

See also in sourсe #XX -- [ Pg.79 ]

See also in sourсe #XX -- [ Pg.79 ]

See also in sourсe #XX -- [ Pg.79 ]

See also in sourсe #XX -- [ Pg.79 ]

See also in sourсe #XX -- [ Pg.79 ]




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