Bis(η-heteroarene) titanium complexes derived from 2,4,6-tri-tert-butylpyridine and 2,4,6-tri-tert-butylphosphorin: Conformational preference in solution and redox activity

The complexes (Ti(NC5H2tBu3-2,4,6)2] 1, and [Ti(PC5H2tBu3-2,4,6)2] 2, have been synthesised in moderate yields via the co-condensation reaction between titanium vapour and [NC5H2tBu3-2,4,6] 3, or [PC5H2tBu3-2,4,6] 4 respectively. The conformation adopted by the molecules in solution has been investigated by NMR and is discussed in comparison with other first row transition metal bis(heteroarene) complexes. Both 1 and 2 are found to exist entirely in the synclinal conformation. The reaction of 1 and 2 with potassium results in formation of the potassium salts K+[Ti(NC5H2tBu3)2−] 5, and K+[Ti(PC5H2tBu3)2−] 6 respectively.