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

• Published in: Journal of chemical sciences (Bangalore, India) India), 2017-02, Vol.129 (2), p.149-156
• Main Authors: CHANG, CHE-WEI, CHIEN, FANG-YUN, HU, JIUN-WEI, TSAI, HSING-YANG, CHEN, KEW-YU
• Format: Article
• Language: English
• Subjects: Chemical bonds; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Chromophores; Conjugation; Density functional theory; Hydrogen bonds; Rapid Communication; Single crystals
• ISSN: 0974-3626; 0973-7103
• DOI: 10.1007/s12039-017-1221-6

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. Graphical Abstract 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.