KO t-Bu-promoted selective ring-opening N-alkylation of 2-oxazolines to access 2-aminoethyl acetates and N-substituted thiazolidinones

Qiao Lin; Shiling Zhang; Bin Li

doi:10.3762/bjoc.16.44

KO t-Bu-promoted selective ring-opening N-alkylation of 2-oxazolines to access 2-aminoethyl acetates and N-substituted thiazolidinones

Beilstein J Org Chem. 2020 Mar 25:16:492-501. doi: 10.3762/bjoc.16.44. eCollection 2020.

Authors

Qiao Lin¹, Shiling Zhang¹, Bin Li¹

Affiliation

¹ School of Biotechnology and Health Sciences, Wuyi University, Jiangmen 529020, Guangdong Province, P.R. China.

Abstract

An efficient and simple KOt-Bu-promoted selective ring-opening N-alkylation of 2-methyl-2-oxazoline or 2-(methylthio)-4,5-dihydrothiazole with benzyl halides under basic conditions is described for the first time. The method provides a convenient and practical pathway for the synthesis of versatile 2-aminoethyl acetates and N-substituted thiazolidinones with good functional group tolerance and selectivity. KOt-Bu not only plays an important role to promote this ring-opening N-alkylation, but also acts as an oxygen donor.

Keywords: N-alkylation; oxazolines; potassium tert-butoxide; ring opening; thiazolidinones.

Grants and funding

We acknowledge the Support of the National Natural Science Foundation of China (No: 21702148), and the Foundation of Department of Education of Guangdong Province (No: 2018KTSCX230, 2017KZDXM085, and 2018KZDXM070).