2‐Propyl‐2‐pentenoic acid was prepared. Its stereochemistry was determined using the A.S.I.S.‐effect. The dehalogenation by N,N‐diethylaniline of some N‐substituted 2‐bromo‐2,2‐dipropyl‐acetamides gave the corresponding unsaturated amides. The configurations of these compounds are discussed on the basis of NMR data obtained with and without complexation with tris(dipivaloylmethano)europium [Eu (DPM)3]