Vi. Minkin et al., SYNTHESIS AND STEREOCHEMICAL NONRIGIDITY OF ISOMERIC ZN(II) BIS-[N-ISOPROPYLOXY(MERCAPTO)NAPHTHALDIMINATES], Russian chemical bulletin, 44(11), 1995, pp. 2168-2171
Kinetics and reaction mechanisms governing inversion of the tetrahedra
l configuration at the metal center in the series of bis-chelate Zn(II
) complexes of 3,2-, 1,2-, and 2,1-oxy(mercapto)naphthaldimines, respe
ctively 4-6, have been studied with the use of dynamic H-1 NMR spectro
scopy. A polytopal rearrangement of the diagonal twist type has been f
ound to be an energetically preferable pathway of the inversion reacti
on for complexes 4 and 5 with a ZnN2O2 coordination site? whereas the
inversion reaction for complexes with a ZnN2S2 coordination site occur
s by an intramolecular dissociation-recombination pathway that involve
s cleavage of a Zn-N coordination bond. In the case of complexes 6, th
e inversion reaction is governed mainly by intramolecular degenerate l
igand exchange reactions.