Process for preparing bis (3,5-dioxopiperazinyl) alkanes or alkenes
US4963679A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 17, 1988 |
| Grant date | Oct 16, 1990 |
| Priority date | — |
| Expiry date | Feb 17, 2008 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D241/08
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A process for preparing a compound of the formula (I) ##STR1## wherein R.sub.1 and R.sub.2 are individually selected from the group consisting of hydrogen and methyl or R.sub.1 and R.sub.2 together represent an ethylene bridge group comprising: PA0 reacting a diamine of the formula (II) EQU H.sub.2 N--CHR.sub.1 --CHR.sub.2 --NH.sub.2 (II) PA0 where R.sub.1 and R.sub.2 are defined as above with formaldehyde and an alkaline metal cyanide at a pH in the range of about 0 to 2 to produce a tetranitrile of the formula (III): EQU (NCCH.sub.2).sub.2 N--CHR.sub.1 --CHR.sub.2 --N(CH.sub.2 CN).sub.2(III) PA0 hydrating said tetranitrile to yield an acid addition salt of a tetraamide of the formula (IV): EQU (H.sub.2 NOCCH.sub.2).sub.2 N--CHR.sub.1 --CHR.sub.2 --N(CH.sub.2 CONH.sub.2).sub.2 .2HX (IV) PA0 where R.sub.1 and R.sub.2 are defined as in formula (I) and X is an acid anion such as fluoride, chloride, bromide or sulfate but preferably chloride; and PA0 reacting said acid addition salt of said tetraamide in a cyclization reaction to yield said compound of the formula (I).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.