in benzene-d6 byproducts: Ag; Zr-compd., Ag-compd. and solvent combined in an NMR-tube, immediate reaction, large excess of Zr-compd.; not isolated, monitored by H-NMR;

in benzene-d6 byproducts: Ag; Zr-compd., Ag-compd. and solvent combined in an NMR-tube, immediate reaction; not isolated, monitored by H-NMR;