A Practical Synthesis of Multi-Site Functionalized Norbornadiene for Molecular Solar Thermal Energy Storage

Abstract Norbornadienes (NBDs) are promising candidates for molecular solar thermal energy storage (MOST) due to their reversible photoisomerization. A central aspect for future application is the scalable synthesis of NBD derivatives with high solubility. Herein, we report an efficient synthesis and purification of multi-substituted NBDs, achieving diverse substitution patterns and appreciable solubility. The streamlined process for synthesizing and purifying NBDs delivers high yields and purity, which addresses previously significant challenges in NBD-based energy systems. Our findings advance sustainable approaches for MOST through improved NBD stability and usability.