J. Petrova et al., DIETHYL 1-SUBSTITUTED 2-OXO-ETHYLPHOSPHONATES AND THE LITHIUM-SALTS AND ZINC COMPLEX OF THEIR ENOL TAUTOMERS, Phosphorus, sulfur and silicon and the related elements, 81(1-4), 1993, pp. 89-94
The lithium salts of diethyl-(1-methyl-2-oxoethyl)phosphonate 1 and di
ethyl-(2-oxo-1-phenyl-ethyl)phosphonate 2 (3 and 4 respectively) as we
ll as the zinc complex of ester 2 (5) are synthesized and characterize
d. The lithium salt 3 exists as a mixture of (Z)- and (E)-forms, while
the lithium salt 4 and zinc complex 5 have (Z)-chelate structure.