Potassium iodide, reaction with ethylene

O ne. Air pollution (qv) levels are commonly estimated by determining ozone through its chemiluminescent reaction with ethylene. A relatively simple photoelectric device is used for rapid routine measurements. The device is caHbrated with ozone from an ozone generator, which in turn is caHbrated by the reaction of ozone with potassium iodide (308). Detection limits are 6—9 ppb with commercially available instmmentation (309). 

Dinitroiodobenzene has been prepared by the nitration of 0- or /)-nitroiodobenzene, by treatment of 2,4-dinitrobenzenedi-azonium sulfate with potassium iodide, and by the reaction of sodium iodide with 2,4-dinitrochlorobenzene in refluxing ethylene glycol. The present procedure is a modification of the last-mentioned one. 

The reaction between ethylene bromide and potassium iodide in 99% methanol (inert) has been found to be first-order with respect to each reactant (second-order overall) (Dillon, 1932). The reaction can be represented by C2liiBr2 + 3K1 —> C2H4 + 2KBr + KI3 or A + 3B - products. 

Diphenylcyclopropane has been prepared in 24% yield by the Simmons-Smith reaction,2 in 78% yield by treatment of 3,3-diphenylpropyltrimethylammonium iodide with sodium or potassium amide,3 in 61% yield by reaction of 1,1-diphenyl-ethylene with dimethylsulfonium methylide,4 and in unspecified yields from 1,1-diphenylethylene by reaction with diazomethane followed by pyrolysis of the resulting pyrazoline or by reaction with ethyl diazoacetate followed by distillation of the corresponding acid over calcium oxide.5... 

R. T. Dillon (1932) studied the reaction between ethylene bromide and potassium iodide in 99% methanol with the following data ... 

Other hazardous reactions may occur with carbon (e.g., soot, graphite, activated charcoal), dimethyl sulfoxide, ethylene oxide, chlorine, bromine vapor, hydrogen bromide, potassium iodide + magnesium bromide, chloride or iodide, maleic anhydride, mercury, copper(II) oxide, mercury(II) oxide, tin(IV) oxide, molybdenum(III) oxide, bismuth trioxide, phosphoms trichloride, sulfur dioxide, chromium trioxide. 

BICHROMATE of POTASH (7778-50-9). Noncombustible, but many chemical reactions can cause fire and explosions. A powerful oxidizer. Violent reaction with many substances, including combustible materials, reducing agents, organic materials, finely divided metals, ammonium nitrate, ammonium perchlorate, fluorine, hydrazine, hydrazinium nitrate, hydrox-ylamine, iron powder, nitric acid, potassium iodide, sodium borohydride, sodium bromide, sodium tetraborate and its decahydrate, tungsten and zirconium dusts. Mixture with sulfuric acid forms chromic acid. Incompatible with ethylene glycol, iron, tungsten. 

QUECKSILBER (German) (7439-97-6) Violent reaction with alkali metals, aluminum, acetylenic compounds, azides, boron phosphodi iodide (vapor explodes), bromine, 3-bromo-propyne, chlorine, chlorine dioxide, ethylene oxide, lithium, metals, methyl silane (when shaken in air), nitromethane, peroxyformic acid, potassium, propargyl hromide, rubidium, sodium, sodium carbide. Forms sensitive explosive products with acetylene, ammonia (anhydrous), chlorine, picric acid. Increases the explosive sensitivity of methyl azide. Mixtures with hot sulfuric acid can be explosive. Incompatible with calcium, sodium acetylide, nitric acid. Reacts with copper, silver, and many other metals (except iron), forming amalgams. 

---