(Z)-9-(2-Propen-1-ylidene)-2-(trifluoromethyl)-9H-thioxanthene is an intermediate used in the synthesis of (E/Z)-Flupentixol-d4 Dihydrochloride (F597982), which is a neuroleptic agent related structurally to thiothixene. Antipsychotic; neuroleptic agent; dopamine receptor antagonist.