Ethane iodides

Perfluoroalkyl)ethane thiols have been used as precursors to fluorinated surfactants and products for hydro- and oligophobic finishing of substrates such as textiles and leather (1). The synthesis of 2-(perfluoroalkyl)ethane thiol and a byproduct bis-(-2-perfluoroalkylethane)-disulfide (5-10%) has been practiced via the reaction of 2-(perfluoroalkyl)ethane iodide with thiourea to form an isothiuronium salt which is cleaved with alkali or high molecular weight amine as shown in Equation 1 for 2-(perfluorohexyl)ethane iodide (1). 

Nucleophihc substitution of sodium thiolate on 2-(perfluorohexyl)ethane iodide leads to extensive elimination (10-20%) and formation of (perfluorohexyl)ethylene (3), Equation 2. 

The olefin yields are higher with 2-(perfluoroalkyl) ethane iodides than their hydrocarbon analogues apparently because of the strongly electron withdrawing fluorine making the hydrogens more acidic and prone to elimination. 

It has been known for many years that 2-(perfluorohexyl)ethane thiocyanate can be synthesized in qnantitative yields from 2-(perfluorohexyl)ethane iodide (4), as shown in Equation 3. 

Perfluorohexyl)ethane iodide was obtained from the Surface Protection Solntions business at DuPont. Sodinm thiocyanate was purchased from Aldrich and nsed without further purificatiom The 2-(perfluorohexyl)ethane iodide was converted to... 

Add 4 0 g. (4 0 ml.) of pure anihne dropwise to a cold solution of ethyl magnesium bromide (or iodide) prepared from 1 Og. of magnesium, 5 0 g. (3-5 ml.) of ethyl bromide (or the equivalent quantity of ethyl iodide), and 30 ml. of pure, sodium-dried ether. When the vigorous evolution of ethane has ceased, introduce 0 02 mol of the ester in 10 ml. of anhydrous ether, and warm the mixture on a water bath for 10 minutes cool. Add dilute hydrochloric acid to dissolve the magnesium compounds and excess of aniline. Separate the ethereal layer, dry it with anhydrous magnesium sulphate and evaporate the ether. Recrystallise the residual anihde, which is obtained in almost quantitative yield, from dilute alcohol or other suitable solvent. 

In 1956 Ames et al. reported that a low yield of l-benzamido-2,2-di-(3-indolyl)ethane (316) was obtained in an attempt to prepare 3-(2-benzamido-l-hydroxyethyl)indole (317) by the action of hcnzamido-acetaldehyde on indole magnesium iodide in ether. 

If in an odoriferous body the atoms with which the possibility of free affinity exists be replaced by others where such possibility does not exist the odour is removed. Thus cacodyl would yield the odourless ethane methyl iodide would give methane ethyl hydro-selenide would yield ethane, and so on. 

A mixture of 22 parts of 1 -ethyl-1,4-dihydro-5H-tetrazol-5-one,45 parts of 1 -bromo-2-chloro-ethane,26 parts of sodium carbonate,0.3 part of potassium iodide and 240 partsof 4-methyl-2 pentanone is stirred and refluxed overnight with water-separator. The reaction mixture is cooled, water is added and the layers are separated. The aqueous phase is extracted three times with dichloromethane. The combined organic phases are dried, filtered and evaporated. The residue is purified by column-chromatography over silica gel using trichloromethane as eluent. The pure fractions are collected and the eluent is evaporated, yielding 28.4 parts (80%) of 1-(2-chloroethyi)-4-ethyl-1,4-dihydro-5H-tetrazol-5-one as a residue. 

Heal content, 110. 116 change (luring a reaction, 110 of a substance, 109 Heat of combustion of diamond, 122 graphite, 122 hydrazine, 47 hydrogen, 40 methane, 123 Heat of formation, 113 Heat of reaction, 135 between elements, table, 112 oxidation of HC1, 160 oxidation of sulfur dioxide, 161 predicting, 112 Heat of reaction to form ammonia, 112 Br atoms, 290 carbon dioxide, 112 carbon monoxide, 112 Cl atoms, 290 CO + Hi, 110 ethane, 112 F atoms, 290 H atoms, 274 hydrogen chloride, 160 hydrogen iodide, 112 iron(Ill) oxide, 162 Li atoms, 290 Li + Br, 290 Li + F, 290 Na + Cl, 290 NHs products, 114 Na atoms, 290 NO, 112 NOj, 112... 

Whilst some organic compounds can be investigated in aqueous solution, it is frequently necessary to add an organic solvent to improve the solubility suitable water-miscible solvents include ethanol, methanol, ethane-1,2-diol, dioxan, acetonitrile and acetic (ethanoic) acid. In some cases a purely organic solvent must be used and anhydrous materials such as acetic acid, formamide and diethylamine have been employed suitable supporting electrolytes in these solvents include lithium perchlorate and tetra-alkylammonium salts R4NX (R = ethyl or butyl X = iodide or perchlorate). 

Somewhat similar observations have been made in the reaction of alkyl halides with sodium mirrors (the Wurtz reaction) in which alkyl coupling occurs. Thus, ethane formed on treatment of methyl iodide with sodium in a field of 20 G shows n.m.r. emission (Garst and Cox, 1970). The phase is consistent with polarization via T j-S mixing,... 

Dioxane reacts with trimethylsilyl iodide 17 to give 96% 1,2-bis-iodoethane, 53% l,2-bis(trimethylsilyloxy)ethane, and 32% HMDSO 7 ]5, 29]. 1,3-Dioxolane 840 furnishes, via 841, iodomethyl-2-iodoethyl ether 842 and HMDSO 7 ]5, 30] (Scheme 6.13). 2-Substituted 1,3-dioxolanes 843 are converted by trimethylsilyl iodide 17, via a series of postulated intermediates, into 1,2-diiodoethane, the ester 844, the alkyl iodide 845, and HMDSO 7 [5] (cf also Chapter 5, Scheme 5.67). 

The reaction of benzotriazoles with aryl halides catalyzed by a mixture of Pd(dppe)Cl2 (DPPE = bis-(diphenylphosphino)ethane) or Pd(dppf)Cl2, copper(I)iodide or copper(II)carboxylates, and a phase-transfer catalyst has been shown to proceed in good yield in DMF solvent.104 Both copper and palladium were required for these reactions to occur at the N-l position in high yields. Similar results for the coupling of amines with aryliodonium salts in aqueous solvent were observed.105... 

The principal competing reactions to ruthenium-catalyzed acetic acid homologation appear to be water-gas shift to C02, hydrocarbon formation (primarily ethane and propane in this case) plus smaller amounts of esterification and the formation of ethyl acetate (see Experimental Section). Unreacted methyl iodide is rarely detected in these crude liquid products. The propionic acid plus higher acid product fractions may be isolated from the used ruthenium catalyst and unreacted acetic acid by distillation in vacuo. 

Acetic acid can be synthesized from methane using an aqueous-phase homogeneous system comprising RhCI as catalyst, CO and 02.17 Side-products included methanol and formic acid, although yields of acetic acid increased upon addition of either Pd/C or iodide ions. The active species is thought to be a CH3-Rh(l) derivative, formed from the C-H activation of methane. The activation of ethane was also achieved, although selectivities were lower, with products including acetic and propionic acids and ethanol (Equation (9)). 

Diethyl malonate reacts with iodine under basic soliddiquid conditions (procedure 6.4.20 omitting the alkene) to produce tetraethyl ethane-1,1,2,2-tetracarboxylate (Scheme 6.28) [110] the ethenetetracarboxylate is also formed, presumably from the reaction of the initially formed iodomalonate with its carbanion and subsequent elimination of hydrogen iodide. 

CHLOROETHANOL ETHYL FLUORIDE ETHYL IODIDE ETHYLENEIMINE ACETAMIDE N-METHYLFORMAMIDE NITROETHANE ETHYL-NITRATE ETHANE... 

General methods for the preparation of /raws-stilbenes have been covered previously. 4,4 -Dimethoxystilbene has been prepared from deoxyanisoin and -propylmagnesium iodide, by treatment of thiophenol with 2-bromo-l,l-di-/>-methoxyphenyl-ethane, and by the action of nitrous acid on the corresponding... 

Malmsten. l,2-Bis(2-ch1oroethoxy)ethane (21.3 g, 0.114 mol) and sodium iodide (37.0 g, 0.247 mol) in acetone (55 ml) were heated at reflux while stirring magnetically during three days. The reaction mixture was allowed to cool, it was filtered, and the filtrate was evaporated under reduced pressure. The residue was dissolved in methylene chloride (200 ml), washed with aqueous 10% sodium thiosulfate solution (2 x 100 ml), dried over magnesium sulfate, and evaporated under reduced pressure. The residual... 

Zur Reduktion von 3,4-Di-2-pyrimidyl-furazan-2-oxid mit Phosphor(III)-iodid/Iodwasserstoff zu 1,2-Diamino-1,2-di-2-pyrimidyl-ethan s. S. 667. 

It was reported that the iodine-zinc exchange process induced by treatment of alkyl iodides with EbZn could be catalyzed by Cul, leading to shorter reaction times and reduction of the amount of Et2Zn38. The use of palladium or nickel catalysts turned out to be also extremely efficient but produced an organozinc iodide instead of a dialkylzinc, with evolution of ethane and ethylene34 (equation 20). 

The gas phase photodecomposition of higher alkyl iodides has received relatively little attention and the contribution made by hot alkyl radicals is uncertain. Schindler and Wijnen6 have compared the rate of production of ethane during the photolysis of pure ethyl iodide, with that in the presence of HI and I2. They assume that in the presence of HI, all the ethyl radicals produced in the primary process form ethane, whereas in the presence of I2 ethane is produced only through reaction of hot ethyl radicals with the parent molecule. Since the rate of production of ethane in the presence of HI is approximately fifty times greater than in the presence of I2, they estimate that <2% of the ethyl radicals produced in the primary process react as hot radicals. 

Methyl iodide (0.2 mL, 3.2 mmol) is added to an ice-cold solution of PdMe2(tmeda) (0.67 g, 2.7 mmol) in acetone (5 mL) in a 100-mL, round-bottomed flask. A yellow precipitate is immediately formed, accompanied by ethane evolution. The suspension is stirred at this temperature for 15 min, after which hexane (80 mL) is added. The bright yellow powder is collected by filtration, washed with hexane (2x10 mL), and dried in vacuo (0.91 g, 94%). The product may be recrystallized via dissolution in dichloromethane (3.5 mL), filtration, and slow addition of hexane (25 mL) to induce slow crystallization. The suspension is then concentrated to 5 mL and the product collected and washed with hexane (10 mL) (0.59 g, 79%). H NMR in CDC13 <52.80-2.45 (m, CH2), 2.63 (s, NMe2), 2.62 (s, NMe2), 0.45 (s, PdMe). 

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