Amines, dibutyl

Man erhalt auf diese Weise z.B. aus Benzyl-methyl-amin Dibenzyl-methyl-amm (24%) und aus Butyl-methyl-amin Dibutyl-methyl-amin ( 60%). In anderen Fallen sind die Ausbeuten z.T. wesentlich schlechter. 

Chlorine, dry Chlorine, water Chromium chloride Chromium sulfate, solution Copper sulfate, solution Decyl acrylate Diamylamine Dibutyl amine Dibutyl phthalate Dichloroether Diethylene glycol Dipropylene glycol... 

Refluxing linoleic acid and a primary or secondary alkyl amine with -toluenesulfonic acid in toluene for 8—18 h also yields the substituted amides (32—34). The reaction of methyl esters with primary or secondary amines to make substituted amides is catalyzed with sodium methoxide. Reactions are rapid at 30°C under anhydrous conditions (35). Acid chlorides can also be used. Ai,A/-dibutyloleamide [5831-80-17 has been prepared from oleoyl chloride and dibutyl amine (36). 

In recent years there has been some substitution of TDI by MDI derivatives. One-shot polyether processes became feasible with the advent of sufficiently powerful catalysts. For many years tertiary amines had been used with both polyesters and the newer polyethers. Examples included alkyl morpholines and triethylamine. Catalysts such as triethylenediamine ( Dabco ) and 4-dimethyla-minopyridine were rather more powerful but not satisfactory on their own. In the late 1950s organo-tin catalysts such as dibutyl tin dilaurate and stannous octoate were found to be powerful catalysts for the chain extension reactions. It was found that by use of varying combinations of a tin catayst with a tertiary amine... 

Catalysts such as dibutyl tin dilaurate or tertiary amines are added to promote the urethane reaction and/or subsequent moisture cure. Dimorpholine diethyl ether is particularly effective at promoting moisture cure without promoting allophanate side reactions at the application temperature (which leads to instability in the hot melt pot) [29]. 

Tetraamination of 2,4,5,6-tetrafluoropyrimidine with dibutyl-amine involves the high reactivity of fluorine as a leaving group rather than activation by the 2,4,6-fluorines. The latter cannot account for the reactivity of the 5-fluorine since the 2,4,6-substituents undoubtedly all react first. Apparently, deactivation by the three dibutylamino groups so introduced (cf. 174) is diminished by steric hindrance to the necessary co-planarity with the ring. 

In the course of this study, the authors determined /Lvalues for dibenzyl, methyl phenyl, methyl p-nitrophenyl, di-p-tolyl, di-isopropyl and tetramethylene sulphoxides and for diethyl, dipropyl and dibutyl sulphites. The /Lscales are applied to the various reactions or the spectral measurements. The /Lscales have been divided into either family-dependent (FD) types, which means two or more compounds can share the same /Lscale, family-independent (FI) types. Consequently, a variety of /Lscales are now available for various families of the bases, including 29 aldehydes and ketones, 17 carboxylic amides and ureas, 14 carboxylic acids esters, 4 acyl halides, 5 nitriles, 10 ethers, 16 phosphine oxides, 12 sulphinyl compounds, 15 pyridines and pyrimidines, 16 sp3 hybridized amines and 10 alcohols. The enthalpies of formation of the hydrogen bond of 4-fluorophenol with both sulphoxides and phosphine oxides and related derivatives fit the empirical equation 18, where the standard deviation is y = 0.983. Several averaged scales are shown in Table 1588. 

Reactions of sulfoxides containing a- and /9-hydrogen atoms, for example n-dibutyl sulfoxide 1170, with trimethylsilyl iodide 17 in the presence of tertiary amines such as diisopropylethylamine (DIPEA) give, e.g., the vinylsulfide 1171 as an 1 1 E/Z mixture in 75% yield and HMDSO 7 [16] (Scheme 8.4). Analogously, the vinyl sulfoxide 1172 or the vinyl sulfoxide 1174 furnish the 1,3-dienyl sulfides 1173 and 1175 in 91 and 85% yield, respectively, and HMDSO 7 [16]. 

Esters, for example, dialkyl polypropyleneglycol adipate and dibutyl adipate, also find use as defoamers in the removal of H2S and CO2 from natural gas by bubbling it through an amine solution [659]. Use of the aforementioned components increases the efficiency of foam destruction. 

Amine-activated zinc dibutyl dithiocarbamate, accelerator. 

The foams can be obtained by the action of a diiscyanate on a polyol and water. The reaction with water forms carbon dioxide and the reaction with polyol forms a urethane polymer. Catalysts play a crucial role in the process. Tin octeate and dibutyl tin dilaurate are preferred catalysts along with tertiary amines. 

The direct potentiometric determination (using a cation-selective membrane electrode) of procaine and some physiologically active amines in pharmaceuticals has been reported [70]. The sensing membrane was formed from PVC plasticized with dibutyl phthalate, and contained 0.1 mM trioctyloxybenzene-sulfonic acid in dibutyl phthalate. The reference solution was a mixture of 1 mM solution of the organic base and hydrochloric acid. Response was found to be linear over a wide concentration range, and the method was highly selective. 

H 1. ohne Amin H3C —COOH/ Dibutyl-ethyl-amin 80 7... 

Many organic reagents have been used successfully in Pu separation processes. The reagents include tri- -butyl phosphate (TBP) methyl isobutyl ketone thenoyl trifluoroacetone (TTA) ethers, eg, diethyl ether, di- -butyl ether, tetraethylene glycol dibutyl ether trilaurylamine (TLA) tnoctyl amine (TOA) di- -butyl phosphate (DBP) hexyl-di(2-ethylhexyl) phosphate (HDEHP) and many others. Of these, TBP is by far the most widely used (30,95). 

Recently, Feng [274] reported a continuous process for the transesterification of EC with methanol in a flow reactor over a dibutyl amine catalyst immobilized on a MCM-41 molecular sieve (n-Bu2N-MCM-41). The catalyst performed well and afforded 25.5% and 41.7% EC conversions at 283 and 323 K, respectively, and also exhibited a good stability. Arai and coworkers [275, 276] subsequently performed the preparation of DMC in two steps (Scheme 7.18). 

Dibutylamine. Into a 1-litre round-bottomed flask furnished with a reflux condenser place a solution of 34 g (18.5 ml) of concentrated sulphuric acid in 100 ml of water add 33 g (0.2 mol) of dibutyl cyanamide and a few fragments of porous porcelain. Reflux gently for 6 hours. Cool the resulting homogeneous solution and pour in a cold solution of 52 g of sodium hydroxide in 95 ml of water down the side of the flask so that most of it settles at the bottom without mixing with the solution in the flask. Connect the flask with a condenser for downward distillation and shake it to mix the two layers the free amine separates. Heat the flask, when the amine with some water distils continue the distillation until no amine separates from a test portion of the distillate. Estimate the weight of water in the distillate and add about half this... 

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