The design of etheric and thioetheric building blocks for polymer synthesis.

A new approach to the design of monomeric and oligomeric ether and thioethers is presented in this article. Nucleophilic aromatic substitution (S N Ar) of cyclopentadienyliron complexes of chloroarenes with a number of aliphatic and aromatic dihydroxy or disulfide nucleophiles, led to the formation of the diiron complexes (2a-g) in very good yields. Some of these sulfur complexes were further oxidized to produce the sulfone complexes (4a-c). Functionalization of the diiron complexes with terminal chloro groups (2a, 2c and4a) was also achieved using S N Ar reactions. The cyclopentadienyliron moieties were removed easily by photolytic demetallation to give the free monomeric and oligomeric ether, thioether and sulfone compounds in yields ranging from 70 to 93%.