One-terminal Wires

Scheme 10.7 depicts the synthesis of an OPE3 one-terminal wire compound by repeated Sonogashira cross-couplings [13c]. The synthesis takes advantage of the more reactive iodide as compared with the bromide, which allows for stepwise scaffolding. Thus, two concomitant Pd-catalyzed cross-couplings of 23 produced 24. The terminal alkyne obtained after desilylation was subsequently cross-coupled with 1 to afford 25. 

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