The primary objective of this study is to develop an immobilized catalyst for transphosphorylation, drawing inspiration from enzymatic processes. To accomplish this goal, a set of key objectives were set. Firstly, the synthesis of TACN (A) and guanidinium (B) ligands is paramount. Then, the next objective is to immobilize these ligands onto a solid resin, establishing a bioactive site through a copper-catalyzed azide-alkyne cycloaddition (CuAAC) "click reaction." Lastly, the study aims to evaluate the catalytic activity of these supported catalysts using the model substrate HPNPP. This assessment seeks to identify optimal conditions for catalytic activation and to elucidate potential cooperativity in the catalytic process.

The focus of this project lies in investigating the catalytic properties of the selected ligands when immobilized on solid resin as an alternative to gold nanoparticles. The investigation includes the characterization of molecules, monitoring reactions through NMR and IR spectroscopy, and evaluating catalytic activity using UV-vis spectroscopy.

TACN (A) was initially synthesized using a protective group, Boc, and this was employed to selectively perform a substitution reaction at the desired site. Subsequently, "click chemistry" was utilized to attach it to the resin. Finally, the protective group was cleaved under acidic conditions.

The synthesis of Guanidinium (B) was approached through three distinct routes. The first route involved a standard substitution reaction, followed by a Staudinger reduction reaction, ending in guanylation. In the second route, with the aim of enhancing efficiency and effectiveness, a different starting material was used and tosylation was performed before following the aforementioned steps. The third route employed a completely different route, employing Gabriel synthesis to obtain the amine, which was eventually subjected to guanylation. Similar to the TACN synthesis, the "click reaction" was employed to immobilize the ligands, and deprotection was achieved through acidic conditions.

We successfully showcased the immobilization of different functional groups onto the Merrifield resin's surface, resulting in the creation of a highly efficient transphosphodiesterase. This achievement holds promise for applications in synthesizing artificial enzymes characterized by great stability compared to their biological counterparts, along with the convenience of recovery and reusability. Our future research endeavors will focus on further enhancing this technology by exploring combinations of the two existing ligands and potentially introducing additional ligands in varying proportions, with the aim of developing artificial enzymes boasting even greater catalytic activities.