Synthesis, Characterization and Optical Properties of Conjugated Boronate-Linked Materials and Their Applications in Optical Sensing of Lewis Bases

Organoboron compounds, with Lewis acidic boron centers, have been emerged as an important class of materials, especially in the area of chemical sensors. Herein, boranes and boronate esters in the sensing perspective were overviewed in Chapter 1. Examples of synthesis and sensing applications of boron-containing conjugated polymers were highlighted. Boronate ester formation provides the advantages of facile synthesis, tunable optical properties, enhanced stability and planar geometry. Thus, boronate esters, especially dioxaboroles, were proposed to use as alternatives of boranes to design better sensors for Lewis bases. Based on the previous investigation of fluorenyl bis- and poly- dioxaboroles by our group, the binding mechanism of dioxaborole based sensors for Lewis bases were discussed in Chapter 2. The binding between dioxaboroles and fluoride was tunable, sensitive, reversible and cross-reactive. The selected fluorenyl bis(dioxaborole)s were employed in cross-reactive sensor arrays for anion differentiation in Chapter 3. Inspired by the extensive research of donor-π-acceptor (D-π-A) boranes, triphenylamino group was attached to borole moiety to form two families of D-π-A boronate esters. Synthesis, characterization, structure and opto/electronic property relationship and sensing applications were investigated in Chapter 4 and 5. Based on the previous work of boronate ester-linked materials in sensors, the future directions were predicted in Chapter 6. The new fluorenyl boroles, D-π-A boroles, cruciform and metal-chelated boronate esters were explored