Strips, Coils, and Bigger Belts

3 The Generality of the Substrate-Directed Approach 3.1 Strips, Coils, and Bigger Belts 

As part of a research program designed (i) to afford macropolycyclic belts of larger ring sizes and (ii) to construct novel acyclic oligomeric molecular strips, an extended bisdiene 57 was identified as a suitable building block to be used in repetitive Diels-Alder reactions. 

Kohnke, John P. Mathias and J. Fraser Stoddart 

Analogous macropolycyclizations starting from 59 have subsequently been performed with the methylene-bridged bisdiene 64 and the octadeuteriated 

Both macropolycyclizations (59 + 64 - 65) and (59 + 66 - 67) proceed in an equally facile manner to that described for the synthesis of the original [14]cyclacene derivative 63. Neither reaction of 64 or 66 with the 2 1 adduct 59 requires high pressure to effect the final ring closure. These facts reinforce the suggestion that the bicyclic bisdienes 64 and 66 with a bicyclo[2.2.1]heptane framework constitute a good stereoelectronic match for the reactive termini present in 59. The resonances 

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