Synthesis of phthalocyanines by microwave irradiation
US6491796B1 · kind B1 · utility
Assignees
Inventors
Key dates
| Filing date | Jun 26, 2001 |
| Grant date | Dec 10, 2002 |
| Priority date | — |
| Expiry date | Jun 26, 2021 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09B47/085
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
This invention provides a novel process for preparing soluble phthalocyanines by microwave irradiation in the absence of any organic solvent. Three different starting materials, i.e. t-butylphthalic anhydride, t-butyl phthalonitrile and metal-free H2Pc (tetra-t-butylphthalocyanine) have been adopted, respectively. The starting material with proper metal compound, such as chloride or acetate were irradiated in a commercial microwave oven for a period of 1 to 30 minutes at a power of 200˜900 W. This process is noted to reduce drastically reaction time of MPc formation from 8˜24 hours to 10˜30 minutes due to its unique heating by microwave irradiation. Sandwiched type MPc2 (such as Lu Pc2) can be produced only through metal replacement from metal-free phthalocyanine by microwave irradiation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.