Patent · US Expired

1,3,4-Oxadiazoles

US4405793A · kind A · utility

7Cited by

1References

3Claims

0Family size

Assignee

Hoechst GmbH · DE

Inventors

Otto Fuchs · Frankfurt am Main, DE
Klaus Hunger · Kelkheim, DE
Dieter Weber · Leonberg, DE
Reinhard Zunker · Kelkheim, DE

Key dates

Filing date	Feb 1, 1979
Grant date	Sep 20, 1983
Priority date	—
Expiry date	Feb 1, 1999

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC09B35/34
WIPO fieldOrganic fine chemistry
WIPO sectorChemistry

Abstract

2,5-Bis-(4'-aminophenyl)-1,3,4-oxadiazoles which are chlorinated in the phenyl nuclei are obtained by condensing hydrazine or a hydrazine yielding agent with equal or different chlorinated benzoic acids or acylating acid derivatives having in para-position to the acid group an amino group or a group capable of being transformed into the amino group, and, thereafter, effecting ring closure of the so-obtained bis-hydrazide to yield the oxadiazole. The products are bis-diazo components, especially for pigments having a very high tinctorial strength, clear and pure shades, a good fastness to light, to heat and to solvents.

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