Synthesis of 15- and 18-membered polythiamacrocylic ligands

✍ Scribed by V. V. Pavlishchuk; P. E. Strizhak

• Book ID: 104783433
• Publisher: Springer US
• Year: 1989
• Tongue: English
• Weight: 216 KB
• Volume: 25
• Category: Article
• ISSN: 0009-3122
• DOI: 10.1007/bf00482505

✦ Synopsis

Reaction of 1,8-dimercapto-3,6-dithioactane with oxa-, aza-, and thiadihaloderivatives under high dilution conditions in the presence of cesium carbonate, which acts as a template for the condensation reaction, produces 15-and 18-membered polythiamacrocyclic ligands in yields greater than 50%.

Polythia-, thiaoxa-, and thiaazamacrocyclic ligands are promising complexing agents, extractants, and detoxicants for a number of transition metals [1][2][3]. Metal complexes of them model the active centers of some enzymes, in particular, the so-called copper-containing blue proteins.

However, synthetic routes to preparation of these compounds has not been as extensively developed as in the case of the polyoxa-and polyazamacrocyclic ligands. The majority of synthetic methods for sulfur-containing macrocycles allows the target product to be obtained only with small yields, except for the Kellog method [4]. Use of this method increases the yields of tetrathia-and oxathiamacrocyclic ligands to 60-80%. The cyclization method proposed in [4] consists of the reaction of dithiols containing esters or thioesters with dibromoderivatives in the presence of cesium carbonate, which acts as a template: