An approach to synthesize a two-dimensional polymer (2DP) using a preorganized host-guest network at the liquid/solid interface is presented. As a host network, we used a self-assembled monolayer of a dehydrobenzoannulene derivative having aminophenyl groups at three alkoxy chain ends and, as a guest, a hexakis(phenylethynyl)benzene derivative having six formyl groups, aiming to connect the host to the guest embedded in the host matrix by imine bond formation. STM observations of host-guest mixtures with trifluoroacetic acid at the 1-phenyloctane/highly oriented pyrolytic graphite interface revealed that the guest was observed as a spoke-like feature in the nanowells. Based on the STM image analysis, short distances between the diagonal phenyl groups in the nanowells are detected, indicating that the imine bonds are formed. However, the small abundance and random distribution of the short phenyl-phenyl distance indicate that the periodically ordered 2DP structure is not formed, probably because the network cannot tolerate the structural change due to partial bond formation.
- Host-guest systems
- Scanning probe microscopy