NMR spectra and configuration of some methylallylic anions

Abstract
The NMR spectra of trans‐ (A) and cis‐3‐methyl‐trans‐l‐phenylallyl anion (B), of cis‐l‐methylpentadienyl anion and of cis‐l‐methyl‐5‐oxapentadienyl anion are described. A is obtained by abstraction of a proton from l‐phenyl‐trans‐2‐butene at low temperature. At 0° it largely isomerizes to B. Several aspects of the configuration of these anions are discussed.