o-Phenylenediamine

• CAS: 95-54-5
• Catalog Number: ALC-FP-95545
• Category: Featured Products
• Molecular Weight: 108.14
• Molecular Formula: C6H8N2
• Boiling Point: 256 - 258 ºC
• Melting Point: 102 ºC
• Appearance: White granular crystal
• Sample Lot No.: 20230503
• Water Content: 0.12% (Karl Fisher)

Case Study

O-Phenylenediamine for the Enhancement of PVDF/LiI/I₂ Polymer Electrolytes in Dye-Sensitized Solar Cells

Sathya K, et al. Materials Science and Engineering: B, 2026, 324, 118907.

In this study, o-phenylenediamine was incorporated into PVDF/LiI/I₂-based polymer electrolytes to evaluate its effect on structural and electrochemical properties for DSSC applications. Solid polymer electrolytes were prepared via solution casting: 0.3 g PVDF, 0.03 g LiI, and 0.006 g I₂ were dissolved in 20 mL DMF, followed by the addition of o-phenylenediamine at 0-50 wt% relative to LiI. The mixture was stirred at 80 °C until homogeneous and cast into glass petri dishes, then dried under vacuum at 60 °C for 12 h to form electrolyte films. SEM and XRD analyses revealed reduced crystallinity and uniform spherical particle formation at 40 wt% doping. This composition exhibited the highest ionic conductivity (4.44 × 10⁻⁵ S cm⁻¹) and, when applied in DSSCs, achieved a peak power conversion efficiency of 3.1%. These results demonstrate the practical utility of o-phenylenediamine in tuning polymer electrolytes for photovoltaic applications.

O-Phenylenediamine in Continuous Flow Synthesis of Benzimidazoles: Experimental Application for Telescoped Monoacylation and Cyclization

Xu Q, et al. Organic Chemistry Frontiers, 2025, 13(3), 917-924.

The continuous flow synthesis of benzimidazoles leveraging O-phenylenediamine demonstrates a highly efficient telescoped approach integrating in-line monoacylation and acid-catalyzed cyclization under short residence times. In practice, equimolar O-phenylenediamines and diverse carboxylic acids are combined in a continuous flow reactor using HBTU activation to promote selective monoacylation of one amine function. The intermediate N-acyl-o-phenylenediamine stream, without isolation, is subsequently passed through an acidic coil reactor (acetic acid) to effect intramolecular cyclization to the corresponding benzimidazole scaffold. Flow conditions - defined reagent introduction, steady heating, and a 20-minute total residence time - enable high conversion across 32 substrate combinations. The process is amenable to gram-scale preparation of pharmaceutical intermediates, exemplified by key precursors for ravidasvir and ledipasvir, confirming both scalability and operational robustness. This methodology highlights O-phenylenediamine's critical role in continuous manufacturing of heterocyclic targets.

O-Phenylenediamine for Green Synthesis of 2-Substituted Benzimidazoles via α-Keto Acid Condensation

Luo Z, et al. RSC Advances, 2025, 15(44), 36803-36807.

O-Phenylenediamine serves as a key bifunctional nucleophile in a green and operationally simple synthesis of benzimidazoles through condensation with α-keto acids under amino acid catalysis. In this method, o-phenylenediamine reacts directly with structurally diverse α-keto acids in water, using a naturally occurring amino acid as an organocatalyst. The reaction proceeds efficiently at room temperature in an open flask under air, eliminating the need for metal catalysts, inert atmosphere, or dehydrating reagents. Mechanistically, initial imine formation between o-phenylenediamine and the carbonyl group of the α-keto acid is followed by intramolecular cyclization and oxidative aromatization to afford 2-substituted benzimidazoles. The experimental protocol highlights the excellent reactivity of o-phenylenediamine under mild aqueous conditions, demonstrating its practical applicability in sustainable heterocycle synthesis with high functional group tolerance and simplified workup.