Synthesis of Thieno[3,4-b]quinoxaline and Derivatives
摘要:
The highly reactive o-quinonoid heterocycles thieno[3,4-b]quinoxaline (1a) and its 6,7-dimethyl derivative (1b) have been synthesized by a base-catalyzed Pummerer reaction and isolated in crystalline form. In contrast, the 1,3-dibromothieno[3,4-b]quinoxaline (8) could be characterized in solution but not isolated in pure farm. The readily prepared 1,3-dihydrothieno[3,4-b]quinoxaline (5a) underwent a direct Knoevenagel condensation with thiophene-2-carboxaldehyde to give the stilbenoid 14a. Sulfide 5a was also converted in a two-step process to the stable 1,3-diformylthieno[3,4-b]quinoxaline 11a.
SOLID ELECTROLYTIC CAPACITOR AND PROCESS FOR THE PRODUCTION THEREOF
申请人:Showa Denko K K
公开号:EP0971382A1
公开(公告)日:2000-01-12
A solid electrolytic capacitor includes a valve acting metal having microfine pores, a dielectric film formed on a surface of the valve acting metal, and a solid electrolyte layer provided on the dielectric film, in which at least a portion of the solid electrolyte layer is of a lamellar structure. In particular, a solid electrolytic capacitor includes an electrically conducting polymer having a specified condensed ring structure containing (1) a solid electrolyte layer containing a sulfoquinone anion having a sulfo anion group and a quinone structure and other anion, and (2) a solid electrolyte layer containing an anthracenesulfonate ion and other anion.