Rylene Diimides Featuring Quadruple C─H···(O═C) Locking for High-Mobility Organic Semiconductors.

Abstract

Polycyclic aromatic hydrocarbons with large conjugated planes and low reorganization energy serve as an ideal molecular platform for organic semiconductors; however, precisely controlling their aggregated structures to achieve large transfer integrals and thus excellent charge transport efficiency remains a significant challenge. Herein, we design and synthesize a sila-annulated hexarylene diimide (2Si-HDI) featuring imide units at both peri-positions and two silole rings at the central bay-positions. Through the quadruple C─H···(O═C) locking between carbonyls of the diimide groups and the hydrogen atoms of the 1,1'-diethylsilyl groups at the silole rings, we realized the first 1D slipped π-π stacking of ultra-long rylenes (naphthalene unit ≥ 6), providing groundbreaking guidance for the well-ordered π-π self-assembly of large planar PAHs relevant to armchair graphene nanoribbons. The single-crystalline organic field-effect transistor properties of 2Si-HDI exhibit hole/electron mobilities up to 3.08/0.06 cm2 V-1 s-1. Theoretical calculations reveal hole/electron transfer integrals of 2Si-HDI as high as 110.08/78.08 meV along the π-π stacking direction, rationalizing its superior charge transport performance.