ChemInform Abstract: Polylithiumorganic Compounds. Part 12. Reductive Scission of a Cyclopropane σ‐Bond During the Action of Elemental Lithium on Cyclopropylacetylenes. A cis‐1,2‐Dilithioalkene as Intermediate.

Abstract The cis‐dilithioalkene (III) is stable in solution at ‐30 °C (trapping experiments with MeOD, (MeO)2SO2, and CO2 (IV) to give, e.g., (V)); above ‐30 °C cyclopropane‐bond cleavage occurs to give a linear intermediate which undergoes elimination of CH2=CH2 followed by deprotonation yielding finally trilithio compound (VI).