Elements of group 1

Effect of Aliphatic Amine Bases on the Aggregation of Alkali Metal Salts of 3,5-Di-tert-butylsemiquinone (3,5-DBSQ)

“…The metal semiquinone solutions were prepared in three steps as shown in the Scheme : (1) alkali metal reduction of 3,5-DBBQ to the 3,5-di- tert -butyl-catecholate dianion (3,5-DBCat); (2) comproportionation of M 2 (3,5-DBCat) and 3,5-DBBQ to yield 2 equiv of M(3,5-DBSQ) isolated as blue solids; (3) addition of solvent and amine. Since Li + , Na + , and K + have coordination numbers ranging from 4 to 8, − a large molar excess of amine was used to ensure coordination saturation and to ensure a high equilibrium concentration of amine-coordinated metal ion, since ether solvents can displace amines 1 …”