5-Stearyloxyisophthalic acid

• CAS: 143294-86-4
• Catalog Number: ACM143294864
• Category: Main Products
• Molecular Weight: 434.62
• Molecular Formula: C₂₆H₄₂O₅
• IUPAC Name: 5-octadecoxybenzene-1,3-dicarboxylicacid
• Canonical SMILES: CCCCCCCCCCCCCCCCCCOC1=CC(=CC(=C1)C(=O)O)C(=O)O
• InChI Key: JAJBICIOMQKJMS-UHFFFAOYSA-N
• Melting Point: 157-161ºC(lit.)
• Appearance: White crystalline powder
• Exact Mass: 434.30300
• WGK Germany: 3

Case Study

5-(Octadecyloxy)Isophthalic Acid Assisted Adsorption of Cu-TCPP on Pyrolytic Graphite

Nicholls, Dylan, et al. The Journal of Physical Chemistry C, 2010, 114(35), 14983-14985.

In this study, 5-(octadecyloxy) isophthalic acid (5-OIA) was chosen as the secondary molecule. This unique diacid features two carboxylic acid groups located at the 3- and 5-positions of its phenyl ring headgroup. The presence of these two sites for hydrogen bonding at one end of the molecular chain allows 5-OIA to create intriguing supramolecular structures on highly ordered pyrolytic graphite (HOPG).
The layer of 5-OIA facilitates the immobilization of copper (II) meso-tetrakis (4-carboxyphenyl) porphyrin (Cu-TCPP) molecules on the HOPG surface. Alongside typical 2D domains, both individual Cu-TCPP molecules and chains of Cu-TCPP molecules have been identified.
A significant point to note is the differing interactions between Cu-TCPP molecules in chains and those in 2D domains with the 5-OIA layer underneath. Cu-TCPP molecules forming chains tend to adsorb at the boundaries of the 5-OIA domains or on the phenyl groups of the 5-OIA molecules. This suggests that chains of Cu-TCPP have a strong tendency to align with certain areas of the 5-OIA layer. This behavior may be attributed to the fact that not all carboxyl groups of the Cu-TCPP in chains are engaged in bonding, allowing the unused groups, which can form hydrogen bonds, to interact with the 5-OIA molecules. Conversely, Cu-TCPP molecules in 2D domains utilize all of their carboxyl groups, which confers rigidity upon the domain and diminishes its interaction with the underlying 5-OIA layer.

Supramolecular Self-Assembly of 5-(Octadecyloxy) Isophthalic Acid on Arylated Graphite

Bragança, Ana M., et al. Chemical Science, 2016, 7(12), 7028-7033.

This work uses a unique approach to control the density of defects on the graphite surface and study their effects on monolayer nucleation and growth of a model molecular system. The defects are generated by covalently grafting aryl radicals on the substrate, and their effects on 2-D crystal formation are probed using 5-octadecyloxy-isophthalic acid (ISA-OC18).
· ISA-OC18 was chosen as the model system for this study. The concentration of ISA-OC18 in the octanoic acid solution was set to 0.2 mM. Self-assembly on bare HOPG at room temperature (20 °C) produces domains of about 1500-4000 nm2 in size, which are easily distinguishable on large-scale STM images (200 nm × 200 nm). All domains belong to the same polymorph consisting of H-bonded two-row isophthalic acid moieties and layered staggered alkoxy chains.
· After adsorption, ISA-OC18 molecules aggregate on the grafted surface, covering the areas between the pins. Due to the randomness of the grafting process, various combinations of pin and ISA-OC18 orientations can be seen.
· As the number of randomly distributed defects rises, the capacity for 2-D crystals to develop around these defect sites diminishes. Compared to ISA-OC18 self-assembly on bare HOPG at 20 °C, low grafting has no significant effect on the size distribution of ISA-OC18 domains, but highly grafted samples contain much smaller domains.