The Four Isomeric 1,3,5‐Undecatrienes. Synthesis and configurational assignment

Abstract

Abstract The four geometrical isomers of 1,3,5‐undecatriene, 1a–d have been prepared (stereospecifically and non‐stereospecifically), using either (1) the Wittig reaction, (2) thermal sigmatropic hydrogen shifts, (3) partial reduction of triple bonds by zinc, or (4) organocopper reagents. The thermal behaviour of the four 1,3,5‐undecatrienes has been investigated and the products formed have been characterized. The spectra of 1a–d, and of related compounds, have been discussed in order to corroborate their configurational assignment.