Thiophene → HCID 68972577, compound

Participants

Reaction Steps

A synthesis for 6,6-dimethyl-6,7-dihydro-5H-4,8-dioxa-2-thia-6-sila-azulene, a silicon-containing EC monomer generally related to 3,4-alkylenedioxythiophene, is shown in FIG. 7. First, 3,4-Dihydroxy-thiophene-2,5-dicarboxylic acid dimethyl ester, the thiophene derivative labeled A7 in FIG. 7 (hereinafter referred to as compound A7) is synthesized from commercially available chemicals according to prior art techniques (see K. Zong, L. Madrigal, L. B. Groenendaal, R. Reynolds, Chem. Comm., 2498, 2002). Note that the same initial step is employed in the synthesis of FIG. 5. Then, a solution of compound A5, dihydroxylmethyldimethylsilane (labeled B7 in FIG. 7), PPh3 (labeled C7 in FIG. 7), and DEAD (labeled D7 in FIG. 7) is refluxed in THF for about 15-24 hours (preferably under an inert atmosphere). A small amount of water is then added to quench the reaction. The reaction mixture is evaporated to dryness. The resulting material is loaded into a silica gel column and eluded by hexane and dichloromethane (2:1, 1:1, volume ratio) to yield 6,6-Dimethyl-6,7-dihydro-5H-4,8-dioxa-2-thia-6-sila-azulene-1,3-dicarboxylic acid dimethyl ester, the silicon-containing thiophene derivative labeled E7 in FIG. 7 (hereinafter referred to as compound E7).

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