H. Otaka, Junya Ikeda, Daisuke Tanaka
Jan 29, 2014
Citations
0
Influential Citations
20
Citations
Journal
Tetrahedron Letters
Abstract
Tetrabutylammonium hydroxide (TBAH) is an efficient and mild alternative to tetrabutylammonium fluoride (TBAF) for base catalyzed cyclizations of 1,2,4-oxadiazoles from O-acylamidoximes. For most 3,5-substituted 1,2,4-oxadiazoles the reactions were dramatically accelerated by addition of 0.1 equiv of TBAH at room temperature. This method was also more generally applicable allowing for a wider range of substrates. Additionally, due to the absence of fluoride, TBAH will not result in corrosion of reactor vessels and therefore is better suited for large-scale synthesis.