Mixed Oligomers Based on Phospholes with Ethenyl or Ethynyl Units

Mixed Oligomers Based on Phospholes with Ethenyl or Ethynyl Units 

X-ray diffraction analysis of the model compound 58 revealed that the C-C linkages between the P-heterocycle and the C = C moieties are rather short [1.423(3)— 1.416(3) A] [47a]. These data suggest that the endocyclic dienic jc-system of the phosphole unit is efficiently conjugated with the two acetylenic substituents. 

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