2,2 ,6",2"-Terpyridine, reaction with

The crude 2,2 -bipyridine obtained from the reaction of pyridine and degassed Raney nickel was found to contain 1.5% of 2 6, 2"-terpyridine, but no 2,2 2, 2" 6 ",2 "-quaterpyridine could be detected. Moreover, experiments with 2,2 -bipyridine and Raney nickel have failed to yield quaterpyridine, and the amount of terpyridine formed in experiments with mixtures of pyridine and 2,2 -bipyridine was found to be no higher than in the reaction with pyridine itself. " ... 

A general strategy developed for the synthesis of supramolecular block copolymers involves the preparation of macromolecular chains end-capped with a 2,2 6/,2//-terpyridine ligand which can be selectively complexed with RUCI3. Under these conditions only the mono-complex between the ter-pyridine group and Ru(III) is formed. Subsequent reaction with another 2,2 6/,2"-terpyridine terminated polymer under reductive conditions for the transformation of Ru(III) to Ru(II) leads to the formation of supramolecular block copolymers. Using this methodology the copolymer with PEO and PS blocks was prepared (Scheme 42) [ 107]. 

Briefly, norbornene-derivatized silica was first reacted with Mo(N-2,6-i-Pr2-C6H3)(CHCMe2Ph)(OCMe(CF3)2)2, followed by (4 -(norbom-2-en-5-ylmethylen-oxy)terpyridine). Loading with Cu (I) afforded the desired ATRP support [18, 22-24], Typical metal loadings were in the range of 15 mmolg. Polystyrene (PS) obtained with these supports under ATRP-conditions showed comparably low poly-dispersities (PDI = 1.55-1.77). The ATRP system consisted of a metal center with one terpyridyl and presumably three acetonitrile ligands, which were at least in part substituted by monomer. Consequently, in contrast to standard systems [25], the equilibrium in this type of reaction did not require conformational... 

The synthesis of the simple dinuclear racks 42-45, incorporating two bis-terpyridine ruthenium(II) co-ordination spheres, has been achieved by reaction of 2.5 equivalents of [Ru(2,2 6, 2 -terpyridine)Cl3] with the appropriate bis-tridentate species, followed by addition of hexafluorophosphate anion. X-Ray diffraction studies have allowed elucidation of the effect of the central R group on the overall shape of the respective molecular racks. Thus, when R = Me (43) there is a straightening of the structure relative to the presence of more bulky alkyl substituents. It... 

In another recent example, a terpyridine fragment has been appended to the lower rim of a fi-CD, and a subsequent reaction with Ru(ttp)Cl3 yielded the complex 47, [(/ -CD-ttp)Ru(ttp)][PF6]2. 

---