Preparation of alkyl-extended, alcohol-extended or amine-extended piperazines
US4927931A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 1, 1988 |
| Grant date | May 22, 1990 |
| Priority date | — |
| Expiry date | Nov 1, 2008 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D295/13
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A process for preparing alkyl-extended, alcohol-extended or amine-extended piperazines or mixtures thereof comprising contacting a difunctional aliphatic alcohol with a reactant amine, wherein at least one of the aliphatic alcohol or the reactant amine contains a piperazine moiety, in the presence of a catalyst containing a Group VB metal oxide or a Group VB metal phosphate, or mixtures thereof. For example, monoethanolamine reacts with piperazine in the presence of a catalyst of niobic acid supported on hydrated alumina to yield predominantly N-(2-aminoethyl)piperazine. Also, N-hydroxyethylpiperazine reacts with piperazine in the presence of a catalyst of niobium phosphate to yield predominantly 1,2-bis(piperazinyl)ethane.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.