Thorium complexes pyridine oxide

Kiplinger and co-workers have also demonstrated dearomatization of pyridines with metals <05CC2591>. In the case reported, thorium complexes mediated ring opening and dearomatization of pyridine Al-oxides yielding the thorium oximate complexes. 

An unusual case of G-H activation with uranium(iv) and thorium(iv) bis(alkyl) complexes has been discovered for pyridine A-oxide. As shown in Scheme 60, addition of 1 equiv. of pyridine A-oxide to a toluene solution of the uranium(iv) bis(alkyl) complexes Gp 2UR2 (R = Me, GH2Ph) unexpectedly resulted in activation of an spz hybridized... 

C-H bond, with loss of alkane and formation of novel cyclometalated pyridine A-oxide complexes in greater than 70% yield. The same reactions could be carried out with the analogous thorium(iv) bis(alkyls).129... 

Table 35 Thorium Tetranitrate Complexes with Pyridine N-oxides. ...

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