NMR Spectroscopic Structural Determination of Organozinc Reagents: Evidence for “Highly Coordinated” Zincates

The structures of ¹³ C-labeled methylzinc reagents have been studied by NMR spectroscopy. Analysis of the spectra gives information on the number of chemically equivalent methyl groups that are attached to the metal centers. Shown is the structure of trimethylzincate with the spin couplings that form the basis of the spin system used in the calculation.