A Straightforward Synthesis of Chlorine‐Bearing Donor–Acceptor Alternating Copolymers with Deep Frontier Orbital Levels

Abstract

Donor–acceptor alternating copolymers with chlorine atoms on the backbone are synthesized via a straightforward Stille polycondensation. Thiophene and chlorine‐substituted 2,3‐diphenylquinoxaline are chosen as the donor and acceptor moieties, respectively. Compared with the corresponding non‐substituted and fluorine‐substituted analogues, which are also synthesized for systematical studies, the chlorine‐bearing copolymer exhibits the deepest lowest unoccupied molecular orbital (LUMO). The highest occupied molecular orbital (HOMO) level of the chlorine‐bearing copolymer can be modified by applying different donor moieties. Additionally, these chlorine‐bearing copolymers show low self‐absorption and large Stokes Shift.

Benzothiadiazole Halogenation Impact in Conjugated Polymers, a Comprehensive Study

“…Such an amplification of the halogen electron-withdrawing effect when using chlorine atoms as compared to fluorine atoms has been already reported by Huang et al and Yang and coworkers in particular. 25,29…”

Chlorination strategy on polymer donors toward efficient solar conversions

“…Bulk heterojunction (BHJ) polymer solar cells (PSCs), comprising conjugated polymer as electron donor and fullerene or nonfullrene derivatives as electron acceptor, have been drawing extensive attentions because of their advantages of low cost, large-area solution processability, light weight, mechanical flexibility and the great potential for commercial applications [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] . Especially the nonfullerence polymer solar cells have shown a new direction for photovoltaic study due to the rapid development in PCE [21][22][23][24] .…”

Synthesis of D‐π‐A‐π type benzodithiophene‐quinoxaline copolymers by direct arylation and their application in organic solar cells

“…Chemical reactions were carried out under argon atmosphere. Intermediates 4,8‐bis‐((2‐ethylhexyl)‐oxy)benzo[1,2‐ b :4,5‐ b ′]dithiophene‐2,6‐di‐yl)bis‐(trimethylstannane) ( 1a ), 4,8‐bis(5‐(2‐ethylhexyl)‐thiophen‐2‐yl)benzo[1,2‐ b :4,5‐ b ′]dithiophene‐2,6‐diyl)bis(trimethylstannane) ( 1b ), 2,6‐dibromo‐4,8‐bis((2‐ethylhexyl)oxy)benzo[1,2‐ b :4,5‐ b ′]di‐thiophene ( 1c ), 2,6‐dibromo‐4,8‐bis(5‐(2‐ethylhexyl)thiophene‐2‐yl)benzo[1,2‐ b :4,5‐ b ′]dithiophene ( 1d ), 5,8‐bis(5‐bromo‐thiophen‐2‐yl)‐6,7‐difluoro‐2,3‐bis(3‐(octyloxy)‐phenyl)‐quinoxaline ( 2a ), and 6,7‐difluoro‐2,3‐bis(3‐(octyloxy)phenyl)‐5,8‐di(thio‐phene‐2‐yl)quinoxaline ( 2b ) were prepared according to procedures described in the literature. The synthesis of 2c is described in the Supporting Information.…”