Crystal structure and solvent-dependent behaviours of 3-amino-1,6-diethyl-2,5,7-trimethyl-4,4-diphenyl-3a,4a-diaza-4-bora-s-indacene

Acta Crystallographica Section E: Crystallographic Communications

Rameez Chaviwala¹  Hongbin Yan¹  Lijing Yang¹  Razvan Simionescu¹  Brett Drew¹  Ravi Shekar Yalagala¹  Alan J. Lough² 

[1] Department of Chemistry, Brock University, 1812 Sir Isaac Brock Way, St Catharines, Ontario, L2S 3A1, Canada;Department of Chemistry, University of Toronto, 80 St George Street, Toronto, Ontario, M5S 3H6, Canada;

关键词: crystal structure;    BODIPY;    excitation and emission;    fluorescence;    NMR spectroscopy;    solvent dependence;   

DOI  :  10.1107/S2056989017002213

来源: DOAJ

【 摘 要 】

In the title compound (3-amino-4,4-diphenyl-BODIPY), C28H32BN3, the central six-membered ring has a flattened sofa conformation, with one of the N atoms deviating by 0.142 (4) Å from the mean plane of the other five atoms, which have an r.m.s. deviation of 0.015 Å. The dihedral angle between the two essentially planar outer five-membered rings is 8.0 (2)°. In the crystal, molecules are linked via weak N—H...π interactions, forming chains along [010]. The compound displays solvent-dependent behaviours in both NMR and fluorescence spectroscopy. In the 1H NMR spectra, the aliphatic resonance signals virtually coalesce in solvents such as chloroform, dichloromethane and dibromoethane; however, they are fully resolved in solvents such as dimethyl sulfoxide (DMSO), methanol and toluene. The excitation and fluorescence intensities in chloroform decreased significantly over time, while in DMSO the decrease is not so profound. In toluene, the excitation and fluorescent intensities are not time-dependent. This behaviour is presumably attributed to the assembly of 3-amino-4,4-diphenyl-BODIPY in solution that leads to the formation of noncovalent structures, while in polar or aromatic solvents, the formation of these assemblies is disrupted, leading to resolution of signals in the NMR spectra.

【 授权许可】

Unknown