Triazole‐diones and naphthoquinone are shown to add in a photochemical [4+2] reaction to the strongly twisted title diene 1. With 1, 4‐naphthoquione, the process is also accompanied by a [2+2] cycloaddition. When the pure atropisomer (−)‐1 is irradiated in presence of 2, 3‐dichloro‐ 1, 4‐naphthoquinone (9), the axial chirality of the diene is preserved. Moreover, it is found to exert complete control over the chirality induced in the resulting spiro‐dihydropyrane 10. Absolute configuration are determined by X‐ray crystallography. In absence of a photo‐dienophile, the axially chiral, dextrorotatory 6‐phenyldibenzo[a,ccyclootene] ((++)‐11) undergoes a stereospecific electrocyclization to give levorotatory 4b,6a‐dihydro‐5‐phenylcyclobuta[l]phenanthrene ((−)‐13). Thus, only one out of two possible, disrotatory modes of ring closure is preferred.