The cathodic reduction of dibenzofuran (2), 2‐chlorodibenzofuran (4), and 3‐chlorodibenzofuran (1) in deuterated methanol is investigated. The Birch‐type reduction product 1,4‐dibenzofuran (3) is formed from 1 via 2, whereas 2‐chloro‐1,4‐dihydrodibenzofuran (5) is obtained as by‐product besides 3 from 4 as starting compound. Deuterium is only incorporated into the reduction products if CH3OD or CD3OD but not if CD3OH are used. This observation is strongly indicative of a polar mechanism involving protonation rather than a radical mechanism with hydrogen atom abstraction to be operative.

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