title: meso-Thiaporphyrinoids revisited: missing of sulfur by small metals.
abstract: Facile synthesis of meso-aryl-substituted 5,15-dithiaporphyrins and 10-thiacorroles has been achieved by sulfidation of α,α'-dichlorodipyrrin metal complexes with sodium sulfide in DMF. Thiacorrole metal complexes exhibit distinct aromaticity due to 18 π-conjugation including the lone pair on sulfur, whereas dithiaporphyrins are nonaromatic judging from (1)H NMR spectra, X-ray analysis, and absorption spectra. We have found that Ni(II) and Al(III) dithiaporphyrin complexes undergo smooth thermal sulfur extrusion reaction to give the corresponding thiacorrole complexes, whereas free base, Zn(II), Pd(II), and Pt(II) dithiaporphyrin complexes did not exhibit the similar reactivity. The DFT calculations have elucidated a reaction pathway involving an episulfide intermediate, which can explain the markedly different reactivity among dithiaporphyrin metal complexes.
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Kamiya
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kondo
authors.forename: Takafumi
authors.initials: T
authors.lastname: Sakida
authors.forename: Shigeru
authors.initials: S
authors.lastname: Yamaguchi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Shinokubo