Hein’s complex

As an example of rearrangements induced by a reaction on the metal, the rearrangement of tri-tr-phenylchromium (1) to bis(biphenyl)chromium(0) (3) and benzenebiphenylchromium(O) (2) (Hein s complexes) can be discussed (1,12). The tr complex (1) is prepared by the reaction of three equivalents of phenylmagnesium bromide with one equivalent of tris-tetrahydro-furanchromium(III) chloride. 

---