N4,N4'-Bis(4-ethenylphenyl)-N4,N4'-di-1-naphthalenyl-[1,1'-biphenyl]-4,4'-diamine
[CAS# 1010396-31-2]

Identification

• Classification: Pharmaceutical intermediate >> OLED material intermediate
• Name: N4,N4'-Bis(4-ethenylphenyl)-N4,N4'-di-1-naphthalenyl-[1,1'-biphenyl]-4,4'-diamine
• Synonyms: VNPB; N,N'-Bis(naphthalen-1-yl)-N,N'-bis(4-vinyl-phenyl)benzidine
• Molecular Formula: C₄₈H₃₆N₂
• Molecular Weight: 640.81
• CAS Registry Number: 1010396-31-2
• SMILES: C=CC1=CC=C(C=C1)N(C2=CC=C(C=C2)C3=CC=C(C=C3)N(C4=CC=C(C=C4)C=C)C5=CC=CC6=CC=CC=C65)C7=CC=CC8=CC=CC=C87

Properties

• Solubility: Insoluble (1.5E^-9 g/L) (25 °C), Calc.^*
• Density: 1.192±0.06 g/cm³ (20 °C 760 Torr), Calc.^*
• Index of Refraction: 1.737, Calc.^*
• Boiling Point: 825.3±65.0 °C (760 mmHg), Calc.^*
• Flash Point: 359.9±22.1 °C, Calc.^*

^* Calculated using Advanced Chemistry Development (ACD/Labs) Software.

Safety Data

• Hazard Symbols: GHS07 Warning
• Risk Statements: H302-H315-H319
• Safety Statements: P501-P270-P264-P280-P302+P352-P337+P313-P305+P351+P338-P362+P364-P332+P313-P301+P312+P330

Discovery and Applications

N4,N4'-Bis(4-ethenylphenyl)-N4,N4'-di-1-naphthalenyl-[1,1'-biphenyl]-4,4'-diamine, commonly referred to as a derivative of tetraaryldiamine compounds, has garnered attention for its significant applications in organic electronics. The molecule was first synthesized in the context of developing advanced hole-transport materials for organic light-emitting diodes (OLEDs). Researchers in the late 20th century identified the potential of such triarylamine derivatives due to their excellent charge transport properties and thermal stability. This compound is characterized by its biphenyl core, flanked by naphthalenyl and ethenyl-substituted phenyl groups, contributing to its rigidity and extended conjugation.

The synthesis of N4,N4'-Bis(4-ethenylphenyl)-N4,N4'-di-1-naphthalenyl-[1,1'-biphenyl]-4,4'-diamine typically involves palladium-catalyzed coupling reactions. The key steps include the use of Buchwald-Hartwig amination to form the biphenyl-diamine structure, followed by Suzuki-Miyaura coupling to attach the naphthalenyl groups. The final step involves a Heck reaction to introduce the ethenyl groups onto the phenyl rings. These methods provide a high yield and allow for structural modifications to optimize electronic properties for specific applications.

One of the primary applications of this compound is in the field of OLEDs, where it serves as a hole-transport material (HTM). Its high thermal and morphological stability ensures efficient charge transport, which is essential for the longevity and performance of OLED devices. This compound also finds use in organic photovoltaic (OPV) cells and other optoelectronic devices, where it enhances charge mobility and device efficiency. The extended conjugated system and bulky side groups reduce intermolecular interactions, minimizing aggregation and improving film-forming properties.

In addition to electronics, this compound has potential in developing sensors and electrochromic devices due to its redox activity. Researchers are exploring its use in new-generation flexible displays and lighting systems, where stability and efficiency are critical. Its versatility in electronic applications highlights the importance of molecular design in advancing organic electronic materials.

References

2021. Cross-linked hole transport layers for high-efficiency perovskite tandem solar cells. Science China Chemistry, 64(12).
DOI: 10.1007/s11426-021-1059-1