TREN amine

A clathrochelate binucleating trom ligand was synthesized via two-step condensation of the tripodal tren amine with 2-oxy-5-methylisophthalaldehyde (Scheme 86) [192]. 

At constant concentrations of Al(OH)3,3D pyrochlore is always obtained at small HF and amine contents this feature is consistent with the hydroxylation and the inorganic nature of this pyrochlore Al2[Fo.5(OH)o.5]6 H2O. With tren amine, the crystallization domain of pyrochlore is shifted towards higher Al(OH)3/HF ratios when [Al ] increases though the [HF + F ] concentration increases in the solution. 

Fe(6-Mepy)3tren](PF6)2- Within the series of iron(II) complexes of the type [Fe(6-Mepy)3 (py) tren](PFg)2 containing the hexadentate ligand tris[4-(6-R)-2-pyridyl]-3-aza-3-butenyl]amine, R = H or CH3, the compounds with X = 1, 2 show a similar HS <- LS transition in solution as well as in the solid state [170]. In solution, spin-state conversion rates have been obtained as shown in Table 3. The complex with x = 0 is pure HS in solution, whereas in the solid state a gradual transition is observed extending over the range... 

Tris(2-aminoethyl)amine (tren) and hexamethyl tren form pentacoordinate complexes with a bound water. The enthalpies of ionization have been determined.242 These results dispute the data from the systems that led to the view that solvent structure mediates the pAia of zinc bound water in zinc hydrolytic enzymes. The effect was shown to be entirely enthalpic. 

Chapman et al. [131] reported the synthesis of poly(ethylene oxide) (PEO) supported dendritic f-BOC-poly(a, c-L-lysines). These dendritic polymers termed as hydramphiphiles formed foams possessing good temporal stability in aqueous solution. Scrimin et al. [132] synthesized a three-directional polypeptide having uses in membrane permeability modulation. Decapeptide fragments were linked to TREN [tris(2-aminoethyl)amine] core. 

Severin and coworkers reported (146) the reaction of tris(2-aminoethyl)amine and 4-formylphenylboronic acid with penta-erythritol to give, via multicomponent assembly, the boronic acid based macrobicyclic cage 35 (Fig. 25). The cage has the form of an ellipsoid with a diameter of 20.5 A and binds two Cud) ions in a fashion similar to the smaller tren-based cryptands. The reversible formation of boronic esters has also been employed to build other hollow structures such as nanotubes (147) and porous covalent organic frameworks (148,149). 

The branched tetradentate ligand tris(2-aminoethyl)amine (tren) forms rather stable metal complexes with most transition metal ions. It is a very hard and basic ligand and consequently its iron(II) complexes are all high-spin. Later we will discuss hexadentate derivatives of this ligand which form crossover complexes (see Sect. 3.2). 

An associative character was also found in the study of the water exchange on [Cu(tmpa)(H20)]2+ (with tmpa = tris(2-pyridylmethyl) amine) (88). The exchange rate constant of 8.6 X 106 s1 at 298 K is only three times larger than in the tren case a AV of -3.0 0.1 cm3 mol1 shows that the process is associatively activated. 

Co(tren)(AAO)]2+ starting complex Amine AA OMe Reaction time Temp (°C) [Co(tren)(AA-AA OMe)] product % Epimerization... 

Figure 15 Examples of artificial collagen model peptide knots, (a) Regioselective artificial cystine knot, (b) dilysine scaffold,(c) c/s,c/s-1,3,5-trimethylcyclohexane-1,3,5-tricarboxylic acid Kemp tri acid , (d) TREN-(suc-OH)3, (Tris(2-aminoethyl)amine) succinic acid, (e) Fe + [2,2 -bipyridyl-peptide]3, " (f) monoalkyl chains, " (g) Boc-/3-Ala-TRIS-(OH)3 knot, and (h) N-terminal GFGEEG link. ...

N3N, TREN Tris(2-(trimethylsilylamido)ethyl)amine, ((CH3)3SiNCH2CH2)3N... 

F. HEXAKIS CYANO(TRIS(2-AMINOETHYL)AMINE)COPPER(II) -CHROMIUM(III) NONAPERCHLORATE HYDRATE, [ Cu(tren)(CN) 6Cr][C104]9 H2O... 

C6Hi4Cl2N202Pt, Platinum(ll), cw-dichlorobis-(propanoneoxime)-, 34 82 C6Hi4Cl2N202Pt, Platinumfll), trani-dichloro-bis(propanoneoxime)-, 34 83 C6H18N4, tren, Tris(2-aminoethyl)amine, complex with copper(II), 34 138 CfiNNaOsW, Tungstate(O), pentacarbonylcyano-, sodium, 34 162... 

The p3-bridged carbonato complex posseses a pseudo-3-fold molecular symmetry. Each of the Cu atoms is five coordinate with the four nitrogen atoms of tren and one oxygen atom of the carbonate ligand (C). The coordination polyhedron of the Cu atom can be described as almost (TBP), the copper ions being slightly out of the plane (0.15 A) of the three primary amine groups (Fig. 5). 

---