Transetherification of 2,4-dimethoxynitrobenzene by aromatic nucleophilic substitution

PLoS One. 2017 Aug 23;12(8):e0183575. doi: 10.1371/journal.pone.0183575. eCollection 2017.

Abstract

In view of the few reports concerning aromatic nucleophilic substitution reactions featuring an alkoxy group as a leaving group, the aromatic nucleophilic substitution of 2,4-dimethoxynitrobenzene was investigated with a bulky t-butoxide nucleophile under microwave irradiation. The transetherification of 2,4-dimethoxynitrobenezene with sodium t-butoxide under specific conditions, namely for 20 min at 110°C in 10% dimethoxyethane in toluene, afforded the desired product in 87% yield with exclusive ortho-selectivity. A variety of reaction conditions were screened to obtain the maximum yield. The aromatic nucleophilic substitution of 2,4-dimethoxynitrobenzene with t-butoxide should be carried out under controlled conditions in order to avoid the formation of byproducts, unlike that of dihalogenated activated benzenes. Among the formed byproducts, a major compound was elucidated as 2,4-dimethoxy-N-(5-methoxy-2-nitrophenyl)aniline by X-ray crystallography.

MeSH terms

  • Carbon-13 Magnetic Resonance Spectroscopy
  • Crystallography, X-Ray
  • Ethers / chemistry*
  • Nitrobenzenes / chemistry*
  • Proton Magnetic Resonance Spectroscopy
  • Spectrometry, Mass, Electrospray Ionization

Substances

  • Ethers
  • Nitrobenzenes

Grants and funding

This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIP) (NRF-2015R1A5A1008958). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.