METAL(I) AND METAL(II) DERIVATIVES OF DIETHYL (2-OXO-1-PHENYL) ETHYLPHOSPHONATE: SYNTHESIS, STRUCTURE AND REACTIVITY

Abstract

The synthesis and structures of sodium, potassium, calcium and magnesium derivatives of 2-diethoxyphosphonyl-2-phenylethen-1-01 1 (2, 3, 4 and 5 respectively) are described. The alkaline salts 2 and 3 are proven to be pure (E)-enolates, while the alkaline earth metal complexes 4 and 5 are diastereomeric mixtures of (Z) and (E) enolate. forms. The reactivity of the metal derivatives is studied in reactions of acylation, alkylation and carbonylolefination. Only O-acetylated (6) and O-benzylated (7) products are obtained as a mixture of diastereomers, where the derivatives of (E)-enol forms predominate. The reaction of carbonylolefination of 4 and benzaldehyde does not occur with the choosen conditions.

Key Words:

• Diethyl (2-OXO-1-Phenyl)ethylphosphonate
• Na- and K-salts; Ca- and Mg-complexes; (Z)- and (E)-acetyl derivatives
• (Z)- and (E)-benzyl derivatives; NMR (¹H, ¹³C, ³¹P)