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Enantiomers of chiral ester derivatives containing an amide group, and possessing one or two stereogenic centers were prepared from L‐ and D‐α‐amino acids, and glycine with (S)‐ and (R)‐mandelic acid for probing their chiral recognition as a new class of chiral guests by 1H NMR spectroscopy, since chiral ester derivatives have been rarely used as chiral substrates for chiral recognition by 1H NMR technology. The results indicated that these chiral ester derivatives have been successfully differentiated in the presence of tetraaza macrocyclic chiral solvating agents (TAMCSAs) 1 a–1 c. In order to better understand their chiral discriminating behavior, Job plots, association constants (Ka), and theoretical calculations of (S,S)‐G1 and (R,R)‐G1, as a representative example, were performed, respectively. In order to evaluate their practical application, the 1H NMR spectra of G1 and G9 with various optical purities were measured (up to 98 % ee). In this work, a practical strategy has been effectively established for chiral recognition of chiral ester derivatives containing an amide group and possessing one or two chiral centers in the presence of tetraaza macrocyclic chiral solvating agents 1 a–1 c by means of 1H NMR spectroscopy. [ABSTRACT FROM AUTHOR]

In this study, we investigate the influence of molecular geometry of the donor polymers and the perylene diimide dimers (di-PDIs) on the bulk heterojunction (BHJ) morphology in the nonfullerene polymer solar cells (PSCs). The results reveal that the pseudo 2D conjugated poly[4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b;4,5-b′]dithiophene-2,6-diyl-alt-(4-(2-ethylhexyl)-3-fluorothieno[3,4-b]thiophene-)-2-carboxylate-2-6-diyl)] (PTB7-Th) has better miscibility with both bay-linked di-PDI (B-di-PDI) and hydrazine-linked di-PDI (H-di-PDI) compared to its 1D analog, poly[[4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl]] (PTB7), to facilitate more efficient exciton dissociation in the BHJ films. However, the face-on oriented π-π stacking of PTB7-Th is severely disrupted by the B-di-PDI due to its more flexible structure. On the contrary, the face-on oriented π-π stacking is only slightly disrupted by the H-di-PDI, which has a more rigid structure to provide suitable percolation pathways for charge transport. As a result, a very high power conversion efficiency (PCE) of 6.41% is achieved in the PTB7-Th:H-di-PDI derived device. This study shows that it is critical to pair suitable polymer donor and di-PDI-based acceptor to obtain proper BHJ morphology for achieving high PCE in the nonfullerene PSCs. [ABSTRACT FROM AUTHOR]