1,6-Diaminoperylene bisimide with a highly twisted perylene core

Abstract

1,6-Diaminoperylene bisimide (1) was synthesized and characterized by single-crystal X-ray diffraction. To the best of our knowledge, this is the first time that the structure of 1,6-disubstituted perylene bisimide has been reported. The crystal belongs to triclinic, space group P-1, with a = 10.3966(10), b = 15.3398(16), c = 16.8495(17) Å, α = 79.490(4)∘, β = 87.055(3)∘, γ = 79.423(3)∘, and Z = 2. Compound 1 possesses two intramolecular C–H ⋯N hydrogen bonds, which generate two S(6) ring motifs. The central perylene core of 1 is twisted with dihedral angles of 19.48(2) ∘ and 19.50(2) ∘; this twist configuration induces the axial chirality in this family of perylene bisimide chromophores. Density functional theory (DFT) calculations also show that the core twist angles of 1,6-diaminoperylene bisimide are larger than those of 1,7-diaminoperylene bisimide, which may account for the fact that the 1,7-regioisomer has a more extended effective conjugation length than the 1,6-regioisomer. 1,6-Diaminoperylene bisimide (1) was synthesized and characterized by single crystal X-ray diffraction. The central perylene core of 1 is twisted with dihedral angles of 19.48(2)° and 19.50(2)°; this twist configuration induces the axial chirality in this family of perylene bisimide chromophores.