A divergent, one-pot synthesis of functionalized polyynes has been developed. Beginning with the appropriately substituted dibromoolefinic precursor, a carbenoid Fritsch-Buttenberg-Wiechell (FBW) rearrangement is used to generate the lithium acetylide of a conjugated polyyne framework, and subsequent trapping with carbon-based electrophiles provides for in situ formation of a wide range of di- and triynes. The lithium acetylide formed from the FBW reaction can also undergo transmetalation to provide the corresponding zinc, copper, tin, or platinum acetylides, leading to the divergent formation of symmetrical and unsymmetrical conjugated acetylenes, as well as ynones.

Alkynes Q 0087One-Pot Formation and Derivatization of Di-and Triynes Based on the Fritsch-Buttenberg-Wiechell Rearrangement. -A convenient approach to synthetically important di-and triynes as well as tetra-and hexaynes is developed. Additionally, one-pot synthesis of platinum acetylide complexes is described. -(LUU, T.; MORISAKI, Y.; CUNNINGHAM, N.; TYKWINSKI*, R. R.; J. Org. Chem. 72 (2007) 25, 9622-9629; Dep. Chem., Univ. Alberta, Edmonton, Alberta T6G 2G2, Can.; Eng.) -Jannicke 17-058