endo‐Rule for gold: A highly endo‐selective gold‐catalyzed cycloisomerization of 1,4‐diynes was developed. By employing electron‐rich phosphines and N‐heterocyclic carbenes as ligands, a number of 1,4‐diynes could be cyclized in a desymmetrizing fashion to form dihydrodioxepines and enantiomerically enriched tetrahydrooxazepines (see scheme).