CHEMmunicate: A chemical structure drawing game for building scientific communications skills and enhancing social interactions among first year undergraduate students

Students’ overall experience of university life and their assessment outcomes are partly determined by their engagement with teaching activities, which is in turn influenced by their sense of social cohesion with their peers. In addition to providing pastoral support, in our role as Senior Tutors, we encourage the formation of a more cohesive learning community among chemistry students post-COVID. With the aim of building better connections both between us and the new student cohort and between the students themselves, we have introduced new Senior Tutor Check-In sessions, which are built around a new chemical drawing game: CHEMmunicate. Across the first semester, we held 8 sessions with ca. 12–16 new first year chemistry undergraduate students in which two teams competed to draw chemical structures using yes/no questions (total: 200 participants over two separate cohorts). In this paper, we outline the rules of the game and provide tips for session leaders seeking to implement it at other institutions. Moreover, through analysis of student feedback from questionnaires and a focus group, we demonstrate how CHEMmunicate and the Senior Tutor Check-In sessions can prove beneficial in building student cohesion and enhancing students’ learning of organic chemistry

C–F Bond Insertion: An Emerging Strategy for Constructing Fluorinated Molecules

C–F Insertion reactions, where an organic fragment formally inserts into a carbon-fluorine bond in a substrate, are highly attractive, yet largely unexplored, methods to prepare valuable fluorinated molecules. The inherent strength of C–F bonds and the resulting need for a large thermodynamic driving force to initiate C–F cleavage often leads to sequestering of the released fluoride in an unreactive by-product. Recently, however, several groups have succeeded in overcoming this challenge, opening up the study of C–F insertion as an efficient and highly atom-economical approach to prepare fluorinated compounds. In this article, the recent breakthroughs are discussed focusing on the key conceptual advances that allowed for both C–F bond cleavage and subsequent incorporation of the released fluoride into the product

The biomechanics of amnion rupture: an X-ray diffraction study

Pre-term birth is the leading cause of perinatal and neonatal mortality, 40% of which are attributed to the pre-term premature rupture of amnion. Rupture of amnion is thought to be associated with a corresponding decrease in the extracellular collagen content and/or increase in collagenase activity. However, there is very little information concerning the detailed organisation of fibrillar collagen in amnion and how this might influence rupture. Here we identify a loss of lattice like arrangement in collagen organisation from areas near to the rupture site, and present a 9% increase in fibril spacing and a 50% decrease in fibrillar organisation using quantitative measurements gained by transmission electron microscopy and the novel application of synchrotron X-ray diffraction. These data provide an accurate insight into the biomechanical process of amnion rupture and highlight X-ray diffraction as a new and powerful tool in our understanding of this process

Direct synthesis of acyl fluorides from carboxylic acids using benzothiazolium reagents

2-(Trifluoromethylthio)benzothiazolium triflate (BT-SCF3) was used as deoxyfluorinating reagent for the synthesis of versatile acyl fluorides directly from the corresponding carboxylic acids. These acyl fluorides were reacted with amines in a one-pot protocol to form different amides, including dipeptides, under mild and operationally simple conditions in high yields. Mechanistic studies suggest that BT-SCF3 can generate acyl fluorides from carboxylic acids via two distinct pathways, which allows the deoxyfluorinating reagent to be employed in sub-stoichiometric amounts

C=O Methylenation mediated by organo-alkali metal reagents: metal identity and ligand effects

C=O Methylenation mediated by α-silyl organo-alkali metal reagents, namely Peterson methylenation, is a textbook organic reaction that has been widely employed in synthetic chemistry for over 50 years. The process is performed over two-steps, by isolating the β-silyl alcohol intermediate generated via nucleophilic addition and then subjecting it to elimination. The choices of alkali metal and external Lewis Base ligand play a critical role in the elimination step, but the reasons remain poorly understood. In this work, we have systematically investigated the metal identity and ligand effects in C=O methylenation reactions mediated by MCH2SiMe3 (M = Li; Na; K). We observed pronounced alkali metal cation and ligand effects on the methylenation performance, with K+ and tetrahydrofuran (THF) being optimal. Based upon these learnings, a straightforward new methylenation method has been designed involving carbonyl addition with LiCH2SiMe3, followed by in situ addition of KOtBu in THF, facilitating facile transmetallation-enabled elimination. This strategy enables the methylenation to be achieved in one pot, whilst circumventing the use of KCH2SiMe3. Excellent yields have been achieved for a range of ketones (including enolizable examples) and aldehydes. The method uses commercial solvents and reagents, and can be performed without any requirement for stringent drying or deoxygenation

A Reductive Mechanochemical Approach Enabling Direct Upcycling of Fluoride from Polytetrafluoroethylene (PTFE) into Fine Chemicals

Polytetrafluoroethylene (PTFE) is a highly versatile material that has found widespread application owing to its exceptionally high chemical resistance and thermal stability. However, these properties mean that PTFE disposal is an energy intensive process, producing fluorinated materials which pose serious concerns regarding toxicity and environmental persistence. Herein we report a straightforward mechanochemical approach for the reductive defluorination of PTFE generating an environmentally benign mixture of elemental carbon and sodium fluoride. The process employs cheap and readily available chunks of sodium metal, proceeding rapidly at room temperature, in the absence of any organic solvent to form sodium fluoride (NaF) in 98% yield. The fluoride generated in the process can be directly upcycled into fine chemicals through in situ mechanochemical fluorination reactions, delivering valuable sulfonyl fluoride and acyl fluoride products in excellent yields

High resolution nuclear magnetic resonance spectroscopy of highly-strained quantum dot nanostructures

Much new solid state technology for single-photon sources, detectors, photovoltaics and quantum computation relies on the fabrication of strained semiconductor nanostructures. Successful development of these devices depends strongly on techniques allowing structural analysis on the nanometer scale. However, commonly used microscopy methods are destructive, leading to the loss of the important link between the obtained structural information and the electronic and optical properties of the device. Alternative non-invasive techniques such as optically detected nuclear magnetic resonance (ODNMR) so far proved difficult in semiconductor nano-structures due to significant strain-induced quadrupole broadening of the NMR spectra. Here, we develop new high sensitivity techniques that move ODNMR to a new regime, allowing high resolution spectroscopy of as few as 100000 quadrupole nuclear spins. By applying these techniques to individual strained self-assembled quantum dots, we measure strain distribution and chemical composition in the volume occupied by the confined electron. Furthermore, strain-induced spectral broadening is found to lead to suppression of nuclear spin magnetization fluctuations thus extending spin coherence times. The new ODNMR methods have potential to be applied for non-invasive investigations of a wide range of materials beyond single nano-structures, as well as address the task of understanding and control of nuclear spins on the nanoscale, one of the central problems in quantum information processing