ˈaɪsoʊpˌɛnteɪn səlˈuːʃənz ʌv bˈæɹɪlˌiːn ˌʌndɚɡˈoʊ fˌoʊɾoʊlˈɪɾɪk ˌaɪsoʊmɹəzˈeɪʃən wɛn ˈæsɪtˌoʊn ɪz ˈædᵻd æz ɐ fˌoʊɾoʊsˈɛnsɪtˌaɪzɚ tə pɹədˈuːs sˌɛmɪbˈʊlveɪlˌiːn.
Isopentane solutions of barrelene undergo photolytic isomerisation when acetone is added as a photosensitizer to produce semibullvalene.