Patent · US Expired

Process for manufacturing chlorothianthrenes

US3989715A · kind A · utility

0Cited by
0References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 1, 1975
Grant dateNov 2, 1976
Priority date
Expiry dateAug 1, 1995

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07D339/08
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

Thianthrene in monochlorotoluene, is reacted with excess chlorine in the presence of a Lewis acid catalyst, to yield a mixture of chlorothianthrenes, the major component of which is 2,3,7,8-tetrachlorothianthrene. Recrystallization of the chlorothianthrene mixture from a suitable solvent, such as tetrahydrofuran yields 2,3,7,8-tetrachlorothianthrene of greater than 90 percent purity.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.