Aryl derivatives oligomer synthesis

Discotic liquid crystals of phenylacetylene macrocycles 29 were first reported by Zhang and Moore in 1994 [136]. Their synthesis involves the stepwise build-up of phenylacetylene hexamers [137] followed by a macrocyclization step [138]. The key reactions of the synthesis (Scheme 33) are the palladium-catalysed coupling of aryl iodides and acetylenes, and the selective deprotection steps allowing the ends of the growing oligomer to be distinguished. The synthesis shown is just one of the many possible sequences that can be used to prepare the macrocycles. The mesophase behaviour of the discotic derivatives prepared to date is shown in Table 35 [136]. In some ways... 

Kurata, Kawase, and Oda s group developed a new one-pot fulvene synthesis the method uses the reaction of AiAf-dimethylformamide (DMF) or NJ -dimethyl chlorocarbamate (ClCONMe2) with aryl lithium reagents to provide fulvene derivatives without the isolation of rather unstable precursor ketones (Scheme 6.28a). As shown in Scheme 6.28a, CP anion and the corresponding ketone are generated in situ [61]. The procedure provides a fulvene oligomer 115 without isolation of the precursor ketone 116 (Scheme 6.28b) [62]. 

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