Synthese d'olefines et de polyenes par doublement d'anions a-sulfonyles en presence de sels de nickel (XXII).
Polycondensation d'acides α-aminés par des systèmes iode-phosphites en présence de pyridine ou d'imidazole
✍ Scribed by Le Guilly, Lionel ;Brack, André ;Spach, Gérard
- Publisher
- Wiley (John Wiley & Sons)
- Year
- 1978
- Weight
- 307 KB
- Volume
- 179
- Category
- Article
- ISSN
- 0025-116X
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✦ Synopsis
Abstract
Polymerization of free α‐amino acids with a pair of reagents–an oxidizing agent (iodine) and a reducing agent (phosphonic acid esters)–was achieved in organic medium in the presence of pyridine or imidazole. A standard procedure leading to optically pure polypeptides with degrees of polymerization up to 50 could be established. Polymeric material was also obtained with a dipeptide as monomer. Some preliminary polymerizations with polyfunctional reagents such as poly(4‐vinylpyridine), cyclodiphosphites, or polyphosphites were performed.
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