AbstractThe hitherto unknown stereochemistry of N,N,N′,N′‐tetrasubstituted 2‐arylthioacrylamides1has been determined by X‐ray crystal analysis and systematic NMR‐investigations. Provided that the 2‐aryl group lacks ortho substituents, compounds1exist predominantly as Z‐isomers. In contrast, the major isomer has an E‐s‐trans configuration if the 2‐aryl group is ortho‐substituted. Substitution of the 3‐amino group of1by glycinates, giving 3‐aminothioacrylamides2, generally preserves t