Wr. Cullen et al., CHARACTERIZATION AND NONRIGID BEHAVIOR OF A CARBOXYLATE-BRIDGED RHODIUM DIMER, Canadian journal of chemistry, 72(5), 1994, pp. 1294-1301
s(mu-t-butylacetato)bis(norbornadiene)dirhodium(I) 1 is prepared by a
reaction between pivaloyl camphor and (norbornadiene)rhodium(I) chlori
de dimer. A molecular rearrangement takes place in which the pivaloyl
groups of the pivaloyl camphor starting material are incorporated into
the end product as bridging t-butylcarboxylate ligands. A variable te
mperature H-1 NMR study and corresponding dynamic computer fit of the
NMR data, and crystal structure are reported for the structurally nonr
igid dimer. Crystals of 1 are triclinic, a = 10.454(1), b = 10.817(1),
c = 12.424(1) Angstrom, alpha = 64.904(7), beta = 100.320(7), gamma =
109.382(8)degrees, Z = 2, space group P $($) over bar$$ 1. The struct
ure was solved by heavy atom methods and was refined by full-matrix le
ast-squares procedures to R = 0.070 and R(w) = 0.081 for 3093 reflecti
ons with I greater than or equal to 3 sigma(l).