Synthesis, Characterization and Evaluation of Some Meldrum's Acid Derivatives as Lubricant Additives

Abstract

Aminomethylene Meldrum’s acid derivatives were synthesized by a three-component, one-pot reaction of Meldrum's acid with triethyl orthoformate and different aromatic amines. The prepared compounds were characterized using Fourier transform infrared (FT-IR), nuclear magnetic resonance (1H NMR and 13C NMR) and evaluated as anti-corrosion and anti-rust additives by blending with base lubricating oil, according to the American Society of Testing and Materials (ASTM-D130 and ASTM-D665). The blends of the synthesized compounds with the base lubricating oil showed better anti-rust and anti-corrosion effects than the base oil Blank).

One-Pot Reactions of Triethyl Orthoformate with Amines

“…A series of five 5-arylidene Meldrum's acid derivatives 86 were synthesized in 13-68% yield via Knoevenagel condensation from aryl amine 18, by Pungot et al [77]. More recently, other derivatives of 5-aminomethylene Meldrum's acid 86 have also been successfully synthesized by Al-Messri [78] with different aromatic amines 18, TEOF 1 and Meldrum's acid 85. The reaction proceeded through a Knoevenagel condensation of TEOF 1 with Meldrum's acid 85 to produce an intermediate such as Michael's acceptor, followed by the regioselective addition of Michael's with the exocyclic amino moiety of the amino compound 18 to obtain the corresponding acyclic adducts 86.…”