Chiral single-stranded metallohelix: metal-mediated folding of linear oligooxime ligand

A linear tetraoxime ligand H4L bearing chiral (S)-2-hydroxylpropyl groups at both ends was synthesized. Complexation between H4L with Zn2+ and Mn+ (=Ca2+, Y3+, La3+) afforded helical trinuclear complex [LZn2M]n+. The helical sense was the most effectively induced when Ca2+ was used as the central metal Mn+.