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Tris amine catalyst

They tried Ni catalysts with chelating amine and phosphine ligands in the reaction of phenylzinc bromide with A-benzoyloxymorpholine 2a and observed that in the presence of NiCl2(PPh3)2, n-alkyl, aryl and functionalized arylzinc chlorides can be aminated with A,A-disubstituted O-benzoylhydroxylamines in good yields (Schemes 20 and 21). Attempted amination of secondary and tertiary alkylzinc chlorides failed to yield the expected product. [Pg.314]

In this Sect, we report systematic DSC studies of (i) the constituents of boron tri-fluoride monoethylamine (BF3 NH2C2H5) catalyzed TGDDM-DDS epoxies and their mixtures (ii) the nature of the catalyzed cure reactions and (iii) the environmental sensitivity of the BF3 NH2CzH5 catalyst. DSC studies are also reported on the cure reaction characteristics and environmental sensitivity of commercial prepregs that contain BF3 amine catalysts. [Pg.15]

A linear tetradentate ligand, bpmen [N,N -dimethyl-N,N -bis(2-pyridylmethyl)-l,2-diaminoethane] was reported to allow stereospecific alkane hydroxylation [36, 40], The same holds true for the [Fen(TPA)(CH3CN)2]2+ [TPA = tris(2-pyridylmethyl) amine] catalyst family (Figure 3.3) [35],... [Pg.78]

In 2002, Ley reported the application of resin-bound reagents and polymers towards the synthesis of carpanone [57]. In the final steps towards carpanone, a resin-bound Co(salen) catalyst was used to give the desired intermediate along with the formation of a small amount of aldehyde by-product. To remove this byproduct, a resin-bound tris-amine scavenger was used, yielding the desired product in high purity (Scheme 8.42). [Pg.213]

Das D, Lee Y-M, Ohkubo K, Nam W, Karlin KD, Fukuzumi S (2013) Temperature-independent catalytic two-electron reduction of dioxygen by ferrocenes with a copper(II) tris[2-(2-pyridyl)ethyl]amine catalyst in the presence of perchloric acid. J Am Chem Soc 135(7) 2825-2834... [Pg.71]

This reaction between poly sulfide liquid polymers and epoxy resins is catalyzed or promoted by organic amine compounds. Although a considerable number have been evaluated, final selection has narrowed the list down to a few practical catalysts among which ate DMP-30 , Rohm and Haas) (tri-dimethylamino-methyl phenol), DET (diethylenetriamine), and BDA (benzyldimethylamine). The amine catalysts are used in a fairly high ratio, in most cases 10% based on weight of the epoxy resin. Because of the coreaction of primary amines such as DET, they are more properly classified as reactive hardeners. The general reaction of a polysulfide liquid polymer, an epoxy resin, and a primary amine hardener is ... [Pg.311]

The primary use for 2,4-di-/ f2 -butylphenol is in the production of substituted triaryl phosphites. 2,4-Di-/ f2 -butylphenol reacts with phosphoms trichloride typically using a trialkylamine or quaternary ammonium salt as the catalyst. Hydrogen chloride is formed and either complexed with the amine or Hberated as free hydrogen chloride gas forming the phosphite ester, tris(2,4-di-/ f2 -butylphenyl)phosphite [31570-04-4] (58). The phosphite-based on... [Pg.68]

The route to 3-bromothiophene utilises a variation of the halogen dance technology (17). Preferably, 2,5-dibromothiophene [3141-27-3] is added to a solution of sodamide in thiophene containing the catalyst tris(2-(2-methoxyethoxy)ethyl)amine (l DA-1) (33) at temperatures marginally below reflux. On completion, quenching exothermically Hberates ammonia gas the organic phase is separated, washed, and distilled, and foremnning thiophene is recycled. Material of 97—98% purity is isolated. [Pg.21]

Strong bases, such as potassium acetate, potassium 2-ethylhexoate, or amine—epoxide combinations are the most useful trimerization catalysts. Also, some special tertiary amines, such as 2,4,6-tns(A7,A7-dimethylarninomethyl)phenol (DMT-30) (6), l,3,5-tris(3-dimethylaminopropyl)hexahydro-j -triazine (7), and ammonium salts (Dabco TMR) (8) are good trimerization catalysts. [Pg.343]

All lene Oxides and Aziridines. Alkyleneamines react readily with epoxides, such as ethylene oxide [75-21-8] (EO) or propylene oxide [75-56-9] (PO), to form mixtures of hydroxyalkyl derivatives. Product distribution is controlled by the amine to epoxide mole ratio. If EDA, which has four reactive amine hydrogens, reacts at an EDA to EO mole ratio which is greater than 1 4, a mixture of mono-, di-, tri,-, and tetrahydroxyethyl derivatives of EDA are formed. A 10 1 EDA EO feed mole ratio gives predominandy 2-hydroxyethylethylenediamine [111-41-1], the remainder is a mixture of bis-(2-hydroxyethyl)ethylenediamines (7). If the reactive NH to epoxide feed mole ratio is less than one and, additionally, a strong basic catalyst is used, then oxyalkyl derivatives, like those shown for EDA and excess PO result (8,9). [Pg.41]

Amorphous (most likely atactic) 3,4-polyisoprene of 94—100% 3,4-microstmcture was prepared with a (C2H 3A1—Ti(0—/ -C Hy) catalyst (11). Crystalline 3,4-polyisoprene containing about 70% 3,4-units and about 30% i7j -l,4-microstmcture was prepared using a catalyst derived from iron acetyl acetonate, trialkyl aluminum, and an amine in benzene (37). However, this polyisoprene contained gel and was obtained in poor yield. Essentially gel-free crystallizable 3,4-polyisoprene of 70—85% 3,4-microstmcture with the remainder being cis-1,4 microstmcture was prepared in conversions of greater than 95% with a water-modified tri alkyl aluminum, ferric acetyl acetonate, and 1,10-phenanthroline catalyst (38). The 3,4-polyisoprene is stereoregular and beheved to be syndiotactic or isotactic. [Pg.4]

In this case furoin crystallized from the ethanolic solution upon cooling. The following somewhat simpler procedure may also be used. A solution of 13.4 g (0.05 mol) of catalyst, 96.1 g (1.0 moll of 2-furaldehyde, 300 mL of absolute ethanol, and 30.3 g (0.3 mol) of tri ethyl amine is stirred at room temperature for 12 hr. The product (84.5 g, 88%) crystallizes directly from solution and is isolated by filtration. [Pg.177]

With the success in Lewis acid-catalyzed thiol conjugate addition reactions mentioned above, we further tried to apply the J ,J -DBFOX/Ph-nickel(II) aqua complex catalyst to the catalyzed asymmetric conjugate addition reactions of hydroxyl-amines [88, 89]. However, after some preliminary examinations, we found that... [Pg.288]

Apart from tertiary amines, the reaction may be catalyzed by phosphines, e.g. tri- -butylphosphine or by diethylaluminium iodide." When a chiral catalyst, such as quinuclidin-3-ol 8 is used in enantiomerically enriched form, an asymmetric Baylis-Hillman reaction is possible. In the reaction of ethyl vinyl ketone with an aromatic aldehyde in the presence of one enantiomer of a chiral 3-(hydroxybenzyl)-pyrrolizidine as base, the coupling product has been obtained in enantiomeric excess of up to 70%, e.g. 11 from 9 - -10 ... [Pg.29]

To improve the yield of mono- and dimethylamines, a shape selective catalyst has been tried. Carhogenic sieves are microporous materials (similar to zeolites), which have catalytic as well as shape selective properties. Comhining the amorphous aluminum silicate catalyst (used for producing the amines) with carhogenic sieves gave higher yeilds of the more valuable MMA and DMA. ... [Pg.161]

The reaction occurs at approximately 80-130°C using the proper catalyst. Many catalysts have been tried for this reaction, and there is an indication that the best catalyst types are those of the tertiary amine and quaternary ammonium functionalized resins. This route produces ethylene glycol of a high purity and avoids selectivity problems associated with the hydrolysis of ethylene oxide. [Pg.194]

In the single-stage production of polyurethanes, di-, tri-, or polyisocyanates are mixed directly with molecules containing two or more reactive hydrogen atoms, such as diols, diamines, and dicarboxylic acids. We typically increase the reaction rate by adding amine or organotin based catalysts. The reaction normally occurs rapidly, evolving much heat. In order to ensure... [Pg.387]


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Amination catalyst

Amines Tris amine

Catalysts amine

Phase transfer catalysts using tris amine

Phase-transfer catalysts Tris amine

Tri amines

Tris amin

Tris amine

Tris catalysts

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