Influence of Altering Chlorine Substitution Positions on Photovoltaic Property of Small Molecule Donors for All-Small-Molecule Organic Solar Cells

To deeply investigate the structure-property relationship in organic solar cells (OSCs), one widely used strategy is to design a series of organic photovoltaic materials with same chemical formular but different...

Predicting the substituent effects in the optical and electrochemical properties of N,N′-substituted isoindigos

Isoindigo, the structural isomer of the well-known dye indigo, has seen a major revival recently because of the increasing interest of its use as a potential drug core structure and for the development of organic photovoltaic materials. Highly beneficial for diverse applications are its facile synthesis, straightforward functionalisation and the broad absorption band in the visible range. Moreover, its intrinsic electron deficiency renders isoindigo a promising acceptor structure in bulk heterojunction architectures. Here we present new insights into the substituent effects of N-functionalised isoindigos, developing a reliable and fast in silico screening approach of a library of compounds. Using experimental UV–Vis and electrochemical data increased the accuracy of the TD-DFT method employed. This procedure allowed us to accurately predict the optical and electrochemical properties of N-functionalised isoindigos and the elucidation of the relationship between substituent effects and electronic properties. Graphic abstract

tert-Butyl Bis(4′-(Hexyloxy)-[1,1′-biphenyl]-4-yl)carbamate

New donor building blocks, i.e., triarylamino derivatives, are of great interest for the production of organic photovoltaic materials. In this communication, bis(4′-(hexyloxy)-[1,1′-biphenyl]-4-yl)amine was synthesized in a two-step process via hydrolysis of its tert-butyl carbamate derivative. tert-Butyl bis(4′-(hexyloxy)-[1,1′-biphenyl]-4-yl)carbamate was obtained by Suzuki cross-coupling reaction of tert-butyl bis(4-bromophenyl)carbamate and (4-(hexyloxy)phenyl)boronic acid in the presence of tetrakis(triphenylphosphine)palladium(0). The structure of newly synthesized compounds was established by means of elemental analysis, high resolution mass-spectrometry, 1H, 13C-NMR, IR and UV spectroscopy and mass-spectrometry.