Triethanolamine borate

U.S. Borax Research Corp., Anaheim, California, markets several borate esters under the trademark BORESTER. These include triethanolamine borate (BORESTER 20), tricresyl borate (m- and p-isomers) (BORESTER 8), and the biborate (4) (BORESTER 7). Whereas the chemical name for (4) is given in Table 1, it is commonly referred to as trihexylene glycol biborate [26545-48-2] and is prepared by the reaction of two moles of boric acid and three moles of hexylene glycol. 

For the most part boric acid esters are quantitated by hydrolysis in hot water followed by determination of the amount of boron by the mannitol titration (see Boron compounds, boric oxide, boric acid and borates). Separation of and measuring mixtures of borate esters can be difficult. Any water present causes hydrolysis and in mixtures, as a result of transesterification, it is possible to have a number of borate esters present. For some borate esters, such as triethanolamine borate, hydrolysis is sufftciendy slow that quantitation by hydrolysis and titration cannot be done. In these cases, a sodium carbonate fusion is necessary. 

Determination of Optimal pH for SC-PEG Reactivity. To triethanolamine-borate buffer (0.3 M, 1 mL) at the appropriate pH, a stock solution of N,a-acetyl-lysine (NAL) in water (50 mM, 0.1 mL) was added followed by a stock solution of SC-activated mPEG-5000 in CH3CN (50 mM active acyl, 0.1 mL). The resultant solution was vortexed and incubated at 28 °C for 1 h. A mixture of the same components but leaving out SC-PEG was used as a control. The TNBS assay version of Snyder and Sobocinski (18) was used to determine the unreacted NAL. 

Chelating agents such as triethanolamine borate also behave as latent catalysts at elevated temperatures. Other boron-containing compounds, cadmium or zinc bromide dieth-ylenetriamine, and salts of aluminum acetoacetic ester have also been suggested as curing agents for high-temperature epoxy adhesives. 

If di- or polyalkylation is a problem, the addition of triethanolamine borate to the reaction mixture will suppress overalkylation. Likewise, enolates formed in the presence of EtjB react smoothly to form mono-alkylation products, as illustrated in the following examples. ... 

Lithiumlithium triethylaluminum, sodium triethylboron, sodium triethanolamine borate,- potassium triethylboron and tri-n-butyltin cyclohexanone enolates have been successfully monoalkyl-ated. In Scheme 6 the behavior of the lithium enolate of cyclohexanone (11) and the lithium triethylaluminum enolate upon reaction with methyl iodide is compared. The latter enolate gives better results since no dimethylation products were detected, but clearly the cyclohexanone enolate (11) is much less prone to dialkylation than the cyclopentanone enolate (10). Scheme 6 also provides a comparison of the results of alkylation of the potassium enolate of cyclohexanone, where almost equal amounts of mono- and di-alkylation occurred, with the alkylation of the potassium tiiethylboron enolate where no polyalkylation occurred. The employment of more covalently bonded enolates offers an advantage in cyclohexanone monoalkylations but not nearly as much as in the cyclopentanone case. 

Regioselective alkylations at C-6 of 2-methylcyclohexanone have been accomplished via the alkylation of thermodynamically unstable trisubstituted lithium, lithium triethanolamine borate, potassium triethylboron, tri- -butyltin and benzyltrimethylammonium enolates (c/. 2). Alkylation is faster than equilibration for the more reactive alkylating agents. Although enolate equilibration has been shown to compete with butylation using n-butyl iodide under certain conditions, butylation of the enolate (2 M = Li) in liquid ammonia-THF gave a mixture of cis- and /ra/ij-2-methyl-6-butylcyclohexanone along with 2-methylcyclohexanone in an 83 17 ratio in 90% yield no 2,2-dialkylcyclohexanone was obtained in this reaction (Scheme 8). ... 

For most commercial applications, it is necessary to add some form of accelerator to the formulation to speed the rate of cure. Both acidic and basic accelerators can be used. Consequently, several latent accelerators have appeared on the commercial scene in recent years. Included among these are quaternary ammonium halides such as benzyltrimethylammonium chloride (9 ), stannous octoate ( ), zinc stearate (1 ), extra-coordinate siliconate salts(11), triethanolamine borate (12), triethanolamine titanate (13), and various other metal chelates (14). However, all of these materials have been rejected for one reason or another and... 

The residual dipolar coupling also manifests itself in NMR spectra of dipolar-coupled quadrupolar spin pairs.Wu and Yamada also observed residual dipolar coupling attributed to the N- B dipolar interaction in the NMR spectra of MAS samples of triethanolamine borate. More recently, the effect of the N- B, "B- B, and Mn- Mn residual dipolar interactions on the B and Mn NMR line shapes acquired through MQMAS were also demonstrated. ... 

The etherification between the epoxy and rubber oligomers can occur also at 353 K but requires such catalysts as chromium salts, diisopropylsalicylic acid, triphenylphosphine, betaine, triethanolamine, triethanolamine borate, benzyldiethylamine, or acetyltriethy-lene ammonium bromide. 

HEAT CAPACITIES AND THERMODYNAMIC PROPERTIES OF GLOBULAR MOLECULES. XII. TRANSITION AND FUSION OF TRIETHANOLAMINE BORATE. 

CAS 283-56-7 EINECS/ELINCS 206-003-5 Synonyms Boric acid, tris (2-aminoethyi) ester Ethanol, 2,2, 2"-nitrilotri-, cyclic borate 2,2, 2"-Nitriloethyl borate Triethanolamine borate... 

Triethanolamine Pure C. See Triethanolamine Triethanolamine abietoyl hydrolyzed animal protein. See TEA-abietoyl hydrolyzed collagen Triethanolamine alkylbenzene sulfonate. See TEA-dodecylbenzenesulfonate Triethanolamine borate. See TEA-borate Triethanolamine Cl2-15 alcohols sulfate. See TEA-C12-15alkyl sulfate Triethanolamine coconut acid. See TEA cocoate... 

Triethanolamine borate has the so-called triptych structure, the distorted tetrahedral boron atom forming three B-O bonds (all ca. 1.43 A) and one B-N bond (1.65 A) with the quadridentate ethanolamine ligand. The molecule has the expected approximate three-fold symmetry. 

DGEBA) composition were obtained. Improvements in char formation22 using triethanolamine borate as the curing agent were also found. 

Composition of phenolic resins containing triethanolamine borate are particularly useful for the manufacture of prepreg mats [109]. 

Aq. Na-tetraphenylhorate (Kalignost) added to aq. triethanolamine borate, then dil. acetic acid added to pH 6 triethanolamine tetraphenylborate. Y ca. 100%.—The stability of the ester is caused by a semipolar N -B-bond which is eliminated by addition of tetraphenylborate. R. Neu, Arch. Pharm. 29A, 721 (1961). 

C6H10B2I2S, 2,5 DiiodO 3,4 diethyl 1,2,5-thiadiborolene, 42B, 510 CgH,2BN03, triptych-Boroxazolidine (Triethanolamine borate), 38B, 407 39B, 470... 

M. W. Rathke and A. Lindert. The alkylation of ketone enolates in the presence of triethanolamine borate. Synth. Comm., 1978, 8, 9. 

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