A Stable Triplet‐Ground‐State Conjugated Diradical Based on a Diindenopyrazine Skeleton

High-spin conjugated radicals have great potential in magnetic materials and organic spintronics. However, to obtain high-spin conjugated radicals is still quite challenging due to their poor stability. Herein, we report the successful synthesis and isolation of a stable triplet conjugated diradical, 10,12-diaryldiindeno[1,2-b :2',1'-e ]pyrazine (m-DIP). With the m-xylylene analogue skeleton containing electron-deficient sp2-nitrogen atoms, m-DIP displays significant aromatic character within pyrazine ring and its spin density mainly delocalizes on the meta-pyrazine unit, making it a triplet ground state conjugated diradical. Our work provides an effective "spin density tuning" strategy for stable high-spin conjugated radicals.