AbstractWe report the synthesis and optoelectronic properties of TIPS‐peri‐pentacenopentacene (TIPS‐PPP), a vertical extension of TIPS‐pentacene (TIPS‐PEN) and a low‐band‐gap material with remarkable stability. We found the synthetic conditions to avoid the competition between 1,2‐ and 1,4‐addition of lithium acetylide on the large aromatic dione. The high stability of TIPS‐PPP is due to the peri‐fusion which increases the aromaticity by generating two localized aromatic sextets that are flanked with 2 diene fragments, similar to two fused‐anthracenes. Like TIPS‐PEN, TIPS‐PPP shows the archetypal 2D brickwall motif in crystals with a larger transfer integral and smaller reorganization energy. The high mobility of up to 1 cm² V⁻¹ s⁻¹ was obtained in an organic field‐effect transistor fabricated by a wet process. Also, TIPS‐PPP was used as a near‐infrared (NIR) emitter for NIR organic‐light‐emitting‐diode devices resulting in a high external quantum efficiency at 800 nm.