The synthesis of small boron oxide nanoparticles (NPs) is reported. A sonochemical approach in the presence of a capping agent was employed to produce approximately 4-5-nm-sized BO NPs, including the B isotopically enriched form. The morphology and composition of the NPs were established using transmission electron microscopy and diffraction, respectively. X-ray photoelectron and Fourier transform infrared spectroscopies provided information about surface functionalization of the BO NPs, which can be further modified through a facile, one-step ligand-exchange process. The toxicity of the synthesized NPs was investigated in Chinese hamster ovarian cells, indicating that these systems were nontoxic up to 1.7 mM concentrations.

We demonstrate that the bench-stable closo-hexaborate cluster dianions can engage in a nucleophilic substitution reaction with a wide array of organic and main-group electrophiles without the use of metal catalysts. The resulting molecules containing B-C bonds can be further converted to tricoordinate boron species widely used in organic synthesis. This strategy showcases a unique substitution and deconstruction reaction sequence with a sterically unprotected nucleophile to afford boronic acid pinacol esters without the use of metal catalysis.

Carborane RAFT agents are introduced as tunable multi-purpose tools acting as 1H NMR spectroscopic handles, Raman probes, and recognition units.

Bromination of the luminescent borane, anti-B18H22, via electrophilic substitution using AlCl3 and Br2, yields the monosubstituted derivative 4-Br-anti-B18H21 as an air-stable crystalline solid.

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This study details the design and implementation of an online materials chemistry general education (GE) course during the COVID-19 pandemic. While many pedagogical techniques involving active learning have been established in STEM major courses, their use within STEM general education courses for non-majors are not as well-established. The recently developed GE course at UCLA (termed Chemistry 3: Material World) utilized high-impact practices to introduce students to the scientific process and impart skills of critical thinking and scientific communication through its flexible activities and assignments. Emphasis was placed on collaborative learning, problem-solving, and interpreting scientific information from published reports. Additionally, content focused on social justice and community engagement was introduced throughout several topics (e.g., underrepresentation in science, war on drugs, nuclear proliferation, pollution, and global climate change) to showcase that chemistry is intricately related to bigger societal challenges. This article details our efforts in achieving the course learning outcomes and shares tangible results regarding the assessment of our teaching strategies from student feedback and reflections. We envision that this work will assist faculty in designing inclusive chemistry GE courses that focus on process versus content and adopting our teaching strategies in both in-person and online classrooms.

Host-guest interactions represent a growing research area with recent work demonstrating an ability to chemically manipulate both host molecules as well as guest molecules to vary the type and strength of bonding. Much less is known about the interactions of guest molecules and hybrid materials containing similar chemical features to typical macrocyclic hosts. This work uses in vitro and in vivo kinetic analyses to investigate the interaction of closo-dodecahydrododecaborate derivatives with ferumoxytol, an iron oxide nanoparticle with a carboxylated dextran coating. We find that several boron cluster derivatives can become encapsulated into ferumoxytol and the lack of pH dependence in these interactions suggests that ion pairing, hydrophobic/hydrophilic, or hydrogen bonding are not the driving force for encapsulation in this system. Biodistribution experiments in BALB/c mice show that this system is nontoxic at the reported dosage and demonstrate that encapsulation of dodecaborate-based clusters in ferumoxytol can alter the biodistribution of guest molecules.

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