TREN derivatives

Macrobicyclic cascade cryptands have also been prepared such as the series of bis(tren) derived (tren = tris(2-aminoethyl) amine, see Section 4.4.3) compounds 5.9. The di-nickel(II) and di-copper(II) complexes of the cages with various spacers all bind a metal cation into each tren unit. These metal... 

Tritopic cyclen- and isocyclam- (isocyclam = 1,4,7,11-tetraazacyclotetradecane) based ligands 121 and 122 were prepared according to Scheme 17. Tosylated tren derivative (tren = tris(2-aminoethyl)amine) was cyclized under Richman-Atkins conditions to give the fully tosylated amines in relatively high yield considering the [1+3] reaction <2002JOC9107>. 

Add isophthalaldehyde (1.01 g, 7.5 mmol) to methanol (200 mL) in a 500 mL conical flask equipped with a stirrer bar. Stir to dissolve the solids. Add a solution of tren (0.73 g, 0.75 mL, 5.0 mmol) in methanol (20 mL) dropwise (ca. 15 min) to the clear solution which turns pale yellow during the addition. Once all the tren has been added reflux for 45 min then allow the solution to cool to room temperature. Transfer to a round-bottomed flask and reduce the volume to ca. 75 mL on the rotovap. Place the flask in an ice bath for 30 min then isolate the product, tren-derived cryptand (37), by filtration. 

Increasing steric bulk at tetradentate tripodal ligands prevented dimer formation and stabilized end-on Cu-02 complexes, one of which was crystallographically and spectroscopically characterized (cavity around the copper center was shaped by the ligand (TMG TREN) (Figure 4.13).42 This dramatic result provided additional support for earlier end-on superoxide formulations for the 1 1 copper-dioxygen complexes supported by tripodal ligands (such as TPA or TREN derivatives)... 

Shorter and modular synthesis of hemicryp-tophane-tren derivatives. Oig Lett 13 3706-3709... 

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