Donors and Acceptors Based on Triangular Dehydrobenzo[12]annulenes: Formation of a Triple-Layered Rosette Structure by a Charge-Transfer Complex

We present here the results of studies of the synthesis and properties of donors and acceptors based on triangular dehydrobenzo[12]annulene ([12]DBA) system as a π core. These studies were aimed at controlling the supramolecular crystal structure. Toward this end, the tricyano[12]DBA 2 and dodecafluoro[12]DBA (3) were synthesized as acceptors (A) and the tris(dialkylamino)[12]DBAs 4a−d as donors (D), and their electronic properties were determined by electronic absorption spectroscopy and electrochemical measurements. The main focus, though, was the formation of supramolecular structures in crystals. These compounds form distinct packing patterns as a result of the different intermolecular interactions. Tricyano[12]DBA 2 forms a two-dimensional (2D) sheet structure via hydrogen-bonding interactions, whereas a tilted-stack structure was found for 3 because of the lack of significant intermolecular interactions. Tris(dibutylamino)[12]DBA 4b exhibits a ladder-type 2D structure, probably because of van der Waals interactions between the butyl groups. The most significant finding is that charge-transfer interactions between donor 4a and acceptor 3 combined with their triangular molecular shapes and lateral CH···F hydrogen bonding result in the formation of a 2D rosette structure consisting of two different trimeric (DAD- and ADA-type) sandwich structures with 1:2 and 2:1 A/D ratios, respectively.

本研究旨在探讨基于三角去氢苯并[12]蒽醌([12]DBA)体系的供体与受体的合成及其性质，该体系作为π核。研究旨在控制超分子晶体结构。为此，合成了三氰基[12]DBA 2和十二氟[12]DBA(3)作为受体制剂(A)，以及三(二烷基氨基)[12]DBAs 4a-d作为供体制剂(D)，并利用电子吸收光谱和电化学测量确定了它们的电子性质。然而，研究的重点在于晶体中超分子结构的形成。这些化合物由于不同的分子间相互作用而形成独特的堆积模式。三氰基[12]DBA 2通过氢键相互作用形成二维(2D)片状结构，而由于缺乏显著的分子间相互作用，3呈现倾斜堆叠结构。三(二丁基氨基)[12]DBA 4b表现出梯形2D结构，这可能是由于丁基基团之间的范德华相互作用。最引人注目的是，供体4a与受体3之间的电荷转移相互作用，结合它们三角形的分子形状和横向CH···F氢键，导致形成由两种不同三聚体(DAD型和ADA型)夹心结构组成的2D玫瑰花状结构，其A/D比例为1:2和2:1。