Method for preparation of an intermediate dye product
US6458967B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 22, 2001 |
| Grant date | Oct 1, 2002 |
| Priority date | — |
| Expiry date | Jun 22, 2021 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D345/00
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The present invention provides a novel method for the synthesis of an intermediate dye product having the following formula: whereinL is S, Te, or Se;R1 and R2 are either the same or different aryl or alkyl compounds;R3 is hydrogen or a short chain alkyl group; andZ is an anion.The process to formulate this intermediate compound entails reacting an R1-acetylene compound with an R2-acetylene compound (compounds A) into an enol ether compound with the R1 and/or R2 constituents (compound D). And from compound D, it forms into an intermediate dye compound having an L-based cyclic ring with the R1 and/or R2 constituents (compound F). With compound F the desired dye can be made with a greater overall yield for mass production.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.