Palladium-assisted rearrangement of HC(O)C 6 H 2 (OMe) 3 -3,4,5 to HC(O)C 6 H 2 (OMe) 3 -2,3,4. X-Ray structures of [PdR(PPh 3 )(bipy)](CF 3 SO 3 )[R = C 6 H(CHO)-6,(OMe) 3 -2,3,4 and C 6 H(CHO)-2,(OMe) 3 -3,4,5; bipy = 2,2′-bipyridyl]

The anionic complex [Pd2R2Cl2(µ-Cl)2]2–{1, R = C6H(CHO)-6,(OMe)3– 2,3,4} and the neutral [Pd2R′2(µ-Cl)2]{2, R′= C6H(CHO)-2,(OMe)3-3,4,5} are both obtained by reaction of HgR2 with appropriate palladium precursors; the isomerization of R to R′ was confirmed by X-ray studies of the derivatives [PdR(PPh3)(bipy)](CF3SO3)5 and [PdR′(PPh3)(bipy)](CF3SO3)5′.