The Reaction of Enamino Ketone-Metal Complexes with p-Substituted Benzoyl Chioride

Abstract

Bis(4-anilino-3-penten-2-onato)copper(II) [1] reacted with p-substituted benzoyl chloride (R, a : NO₂, b : Cl, c : H, d : CH₃, and e : OCH₃) and pyridine (2.3 molar ratios to [1] in benzene at 8±2°C for an hour to give C-aroylated product, 4-anilino-3-(p-substituted, benzoyl)-3-penten-2-one [3] (41-86% yield), and 4-substituted benzanilide [4] (-10%). Bis(4-anilino-3-penten-2-onato)nickel(II) [2] was allowed to react similarly with them in the absence of pyridine to give [3] (53-85%) and [4] (-11%). The more the electron attractive substituent at benzene ring, the higher was the yield of [3] (Table 1). The stereochemical structures of all of [3] were (E)-isomers on the basis of the IR and PMR spectral data shown in Table 2 and of the comparison of spectroscopic data with the C-acetylated product, 3-acety-4-anilino-3-penten-2-one [5] (ν_C=O) of the free acetyl group : 1669 cm^-1, ν_C=O of the intramolecular hydrogen-bonded acetyl group : 1592 cm^-1, δ_NH : 1569 cm^-1, and proton signal of NH group : 13.72 ppm (broad)).