Synthesis of Hydrophobically Modified Isoxazolidines for Their Potential Use as Corrosion Inhibitors

A. M. El-Shareefa¹, R. F. Al-Ghamdia¹ and S. A. Ali²

¹Chemistry Department, aDammam Girl's College, Dammam- 31113 (Saudi Arabia) ² King Fahd University of Petroleum and Minerals, Dhahran- 31261 (Saudi Arabia)

Several new isoxazolidines having varying degree of steric environment and hydrophobic alkyl chains are prepared efficiently using single-step nitrone cycloaddition reactions. The resultant 2,5-disubstituted isoxazolidines containing methyl, isopropyl and t-butyl groups at N(2) and alkyl groups C6H13, C10H21, C12H25, C14H29 and C16H33 at C(5) positions are characterized by NMR spectral analyses. At lower temperature (-30°C) the NMR spectra revealed the presence of two distinct interconverting forms of the isoxazolidines due to slow nitrogen inversion process. One of the isoxazolidines was quaternized with I-bromotetradecane and propargyl chloride. The isoxazolidine on ring opening reaction with zinc in acetic acid afforded an 1,3-aminoalcohol. Preliminary study indicated the excellent corrosion inhibition of mild steel in acidic medium by the synthesized compounds.

Isoxazolidine; Corrosion inhibitors; Cycloaddition; Nitrone