Novel dibasic acid salts and their synthesis
US4965397A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 23, 1989 |
| Grant date | Oct 23, 1990 |
| Priority date | — |
| Expiry date | Jan 23, 2009 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P20/55
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The protecting group, Z, of protected alpha-amino acid esters of the formula EQU Z--NH--CH(R.sub.2)COOCH(R)COOR.sub.1 is removed in the presence of a dibasic acid such as oxalic acid. This results in the formation of a new type of salt of an amino acid ester which may be represented by the formula ##STR1## In the above Q is a divalent hydrocarbyl residue of a dibasic acid, R is a hydrogen atom or hydrocarbyl group, R.sub.1 is a hydrocarbyl group, R.sub.2 is a hydrogen atom or hydrocarbyl group, and p is zero or one, preferably zero. When p is zero, the salts are oxalate salts. When p is one, the salts are salts of other dibasic acids. The salts (II) are useful as reactants in the synthesis of amino-acid substituted phosphazene polymers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.