Tri-N-butylamine

A review on TLC and PLC of amino adds, peptides, and proteins is presented in the works by Bhushan [24,25]. Chromatographic behavior of 24 amino acids on silica gel layers impregnated tiraryl phosphate and tri-n-butylamine in a two-component mobile phase (propanol water) of varying ratios has been studied by Sharma and coworkers [26], The effect of impregnation, mobile phase composition, and the effect of solubility on hRf of amino acids were discussed. The mechanism of migration was explained in terms of adsorption on impregnated silica gel G and the polarity of the mobile phase used. 

The required working time is 3 to 4 hours. All equipment is thoroughly dried prior to use and is flushed with an inert gas (argon or nitrogen). Commercial sodium hydroborate is used without purification. The dimethyl ether of diethylene glycol (diglyme) is refluxed over calcium hydride for 8 hours and subsequently distilled over lithium tetrahydroaluminate (lithium aluminum hydride). Commercial tri-n-butylamine is refluxed with acetic anhydride and distilled at atmospheric pressure. 

A maximum in the DP and a minimum in the specific conductivity, both at a ratio of [additive]/ [A1C13] ranging from 0.8 to 1.0 (in EtCl at -78.5°) were also reported for a large range of additives , comprising various alcohols, acetone, methyl benzoate, acetic acid, 1-dodecanethiol, and tri-n-butylamine [66]. For all these additives no details are given, so that it is not known whether the relevant curves have more than one turning point. 

The yields of arenesulphonic acids (-80%) via the reaction of activated haloarenes with potassium sulphite under phase-transfer catalytic conditions [62, 63] are no better than conventional non-catalytic methods, although reaction conditions are less severe. There is evidence that indicates the initial attack by the sulphite anion is at C-5. Surprisingly, tri-n-butylamine is a better catalyst, producing higher yields (>90%). 

Compared with primary and secondary amines, tertiary amines are virtually unreac-tive towards carbenes and it has been demonstrated that they behave as phase-transfer catalysts for the generation of dichlorocarbene from chloroform. For example, tri-n-butylamine and its hydrochloride salt have the same catalytic effect as tetra-n-butylammonium chloride in the generation of dichlorocarbene and its subsequent insertion into the C=C bond of cyclohexene [20]. However, tertiary amines are generally insufficiently basic to deprotonate chloroform and the presence of sodium hydroxide is normally required. The initial reaction of the tertiary amine with chloroform, therefore, appears to be the formation of the A -ylid. This species does not partition between the two phases and cannot be responsible for the insertion reaction of the carbene in the C=C bond. Instead, it has been proposed that it acts as a lipophilic base for the deprotonation of chloroform (Scheme 7.26) to form a dichloromethylammonium ion-pair, which transfers into the organic phase where it decomposes to produce the carbene [21]. 

Trifluoro methane sulfonate Triisopropanolamine Trimethylamine Tri-n-butylamine... 

Tri-n-butylamine hydrobromide [37026-85-0] M 308.3, m 75.2-75-9°. Crystd from ethyl acetate. 

TRI-n-BUTYLAMINE (Table V) Aniline Benzaldehyde Miscibilities with 160 substances 43 <25 151 151 15,296(pp.404-10)... 

The phase-transfer method has also been employed for the carbonylation of benzylic halides to carboxylic acids.477 The palladium(O) complexes [Pd(PPh3)4] (103), [Pd(diphos)2] (104) and [Pd(DBA)2] (105 DBA = dibenzylideneacetone) were used as catalysts. With (103) and (104) the carboxylic acid was the major product. Complex (105) gave little or none of the acid, the toluene and bibenzyl derivatives corresponding to the benzyl halide used being formed. Benzyl esters of the carboxylic acid were sometimes present as minor products. The reaction has been adapted to provide a new synthesis of anthranilic acid derivatives (equation 106).478 Tri-n-butylamine was used to neutralize the HBr formed. 

Benzyl chloride reacts easily with methyl acrylate in the presence of tri-n-butylamine and palladium acetate (1 mol %) as catalyst.51 The product is a mixture of (E)-methyl 4-phenyl-3-butenoate (67%) and (E)-methyl 4-phenyl-2-butenoate (9%), arising from elimination-addition reactions of the palladium hydride group which largely isomerize the initial elimination product. 

Table 3. Hammett reaction constants q for the copolymerization of p-N02, p-C02CH3, p-Cl, p-H, p-CHj, and p-OCH3 substituted phenylglycidyl ethers with hexahydrophthalic anhydride initiated with tri-n-butylamine ...

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