Synthesis of Substituted Norbornadienes

Three-Input Molecular Keypad Lock Based on a Norbornadiene–Quadricyclane Photoswitch

“… 31 Synthesis of norbornadiene derivatives has been explored in the past for their importance as synthetic intermediates, and for other applications. 32 Recently, the research area has seen a resurgence, thanks to the contributions of modern coupling reactions and advanced computational tools. 33 − 39 Most often, the unsubstituted norbornadiene is not ideal for these purposes.…”

“…Norbornadiene is a bicyclic organic compound which upon irradiation with UV light is converted to the highly strained and saturated quadricyclane isomer. − Back-isomerization to the norbornadiene form has been observed thermally, electrochemically, catalytically, and photonically. ,− Norbornadienes have been widely studied over the years for solar thermal energy storage applications. − They have also been studied as molecular electronic components . Synthesis of norbornadiene derivatives has been explored in the past for their importance as synthetic intermediates, and for other applications . Recently, the research area has seen a resurgence, thanks to the contributions of modern coupling reactions and advanced computational tools. − Most often, the unsubstituted norbornadiene is not ideal for these purposes.…”

“…The presented NBD derivative has already many advantages compared to those of previously reported systems, such as the ease of synthesis and the demonstrated robustness over many cycles . Moreover, NBDs synthesis and physical and chemical behaviors and properties are widely studied and quite well understood, ,,,, implying the facilitation of carefully designing molecular systems with the desired properties and predictable physicochemical behavior. Some limitations and challenges can be identified.…”

“…The function is easily rationalized from the underlying isomerization and protonation/deprotonation scheme. The advantage of using NBD derivatives is that NBD chemical modifications have been abundantly explored in the past and more recently, ,,,, which allows us to access a wide library of compounds and synthetic methods. For these reasons there are certainly great opportunities for improved design aiming at more streamlined keypad locks, or complex multiswitch systems allowing for even more sophisticated logic functions to be performed.…”