Mineralization dichloromethane

Carboxylic acids are more acidic than alcohols and acetylene. Strong aqueous bases can completely deprotonate carboxylic acids, and salts of carboxylic acids are formed. Strong aqueous mineral acids readily convert the salt back to the carboxylic acids. Saits are soluble in water but insoluble in nonpolar solvents, e.g. hexane or dichloromethane. 

The simplest chlorinated alkanes, alkenes, and alcohols (e.g., chloromethane, dichloromethane, chloroethane, 1,2-dichloroethane, vinyl chlonde, and 2-chloroethanol) serve as substrates for aerobic growth foi some, bacteria, but the majority of halogenated solvents cannot support growth. Nevertheless these compounds are mineralized under aerobic conditions. 

It has been suggested [95] that the synthesis of structured porphyrins with controllable steric ambience is a strategic direction in the reproduction of enzyme protein cavities, which control the selectivity and stability of biochemical reactions such as cytochrome P-450. Such an approach to the synthesis of biomimics has considerable potential, especially in their application on mineral matrices silicon dioxide, alumina and zeolites. Data exist on the synthesis of a biomimic [96] with a complex porphyrin complex (5-pentafluorophenyl-10,15,20-tri(2,6-dichlorophenyl)porphyrin (FeMPFDCPP)) covalently linked to aminopropyl silicon dioxide, which is applied in oxidation of ds-cyclooctene, cyclohexene, cyclohexane and adamantane with participation of iodosylbenzene dissolved in dichloromethane. 

A solution of N-(4-pyridinyl)-lH-indol-l-amine (6 g) in 25 ml of dimethylformamide was slowly added to an ice-cooled suspension of NaH (1.3 g of 60% NaH dispersion in mineral oil was washed with hexanes, the liquid was decanted and the residual solid was dispersed in 5 ml of dimethylformamide). After anion formation, a solution of 1-bromopropane (4 g) in 5 ml of dimethylformamide was added. After one hour of stirring at ambient temperature, the reaction mixture was stirred with ice-water and extracted with dichloromethane. The organic extract was washed with water and saturated sodium chloride solution, was dried over anhydrous magnesium sulfate, filtered and concentrated to 8 g of oil. This oil was purified by HPLC (silica, ethyl acetate) and thereafter by column chromatography (alumina, ether) to give 6.4 g oil. This oil was converted to the maleate salt and recrystallized from methanol/ether to give 6.8 g of crystals, m.p. 115-116°C. 

Boc is a good labile group because it is stable at room temperature and easily removed with dilute solution of TFA either neat or in dichloromethane. Other mineral acids or Lewis acids have also been used, although less frequently. 

Dichloroethane Dichloromethane Dimethylformamide 1,4-Dioxane Mineral oils (untreated) Tetrachloroethylene Toluene... 

Sc(OTf)3 is more soluble in water than in organic solvents such as dichloromethane. The catalyst can be recovered almost quantitatively from the aqueous layer by simple extraction after the reaction was complete (Sch. 2), and it could be re-used. The recovered catalyst is also effective in the 2nd reaction, and the yield of the 2nd run is comparable with that of the 1st run (Eq. 1) [4], Because Sc(OTf)3 can be successfully recovered and re-used in many other reactions, it is expected to solve severe environmental problems caused by mineral acid- or Lewis acid-promoted reactions in the chemical industry. 

Solubihty freely soluble in chloroform and dichloromethane practically insoluble in ethanol (95%), mineral oil, and water. 

Polarised molecules such as higher molecular-weight hydrocarbons can be adsorbed via electrostatic forces. Organic or inorganic colloids (humic matter and clay minerals) are electrically charged and possess high adsorption capacities. Hydrocarbon gas molecules adsorbed in this way can be released by the addition of more competitive molecules (e.g., dichloromethane) to substitute in the occupied sites. 

Glass-sorbed pyrethroid was measured in the same way after washing off with dichloromethane three times. Control experiments without minerals allowed glass sorption to be independently measured. All experiments were made at least in duplicate. Average recovery was 90%. 

Under an inert atmosphere, prepare a suspension of sodium hydride (0.96 g, 20 mmol [50 per cent in mineral oil]) in dry THF (50 mL) in a 250 mL twonecked round-bottomed flask fitted with a reflux condenser and pressure equalized addition funnel. Stir for 30 min under an inert atmosphere. Slowly add a solution of 8-hydroxyquinoline (2.90 g, 20 mmol) in dry THF (50 mL) to this through the addition funnel. Make up a solution of triethylene glycol ditosylate, 2, (4.60 g, 10 mmol) in dry THF (50 mL), ensuring that no solids remain (filter if necessary) or the addition funnel may become blocked. Once the effervescence subsides following the formation of the sodium 8-hydroxyquinolinate salt, add the ditosylate solution and reflux for 24 h. After 24 h, allow the solution to cool to room temperature, filter off the precipitated sodium tosylate and remove the THF by rotary evaporation. Dissolve the residue in dichloromethane (30 mL) and wash with distilled water (3 x 30 mL). Dry the organic phase over anhydrous sodium sulphate, filter and remove dichloromethane by rotary evaporation to give the crude product, l,9-bis(8-quinolinyloxy)-3,6-dioxanonane (4) as a pale brown oil. Further purification may be afforded by column chromatography (silica, elute with acetone/dichloromethane). 

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