When a small electric bias is applied to a single-molecule junction, current will flow through the molecule via a tunneling mechanism. In molecules with a cyclic or helical structure there may be circ...

The reversible photoisomerization of 1,2-dihydro-1,2-azaborinines (BN benzenes) to their Dewar isomers (2-aza-3-borabicyclo[2.2.0]hex-5-enes) provides a promising platform for molecular solar thermal ...

To unlock the potential of molecular engineering for practical quantum sensing and computing, it is essential to create and control pure magnetic states in molecular systems. Singlet fission (SF) in o...

Over the past decades, carbon allotropes have been extensively studied and applied to various technological applications due to their unique electronic and optical properties. Contemporary research ha...

Fluorescence imaging is crucial for studying biology. Triplet state quenchers (TSQs), especially cyclooctatetraene (COT), can dramatically improve fluorophore performance, particularly when linked int...

As announced in Budget 2024, the scholarship and fellowship programs administered by the three federal research funding agencies – the Canadian Institutes of Health Research (CIHR), the Natural Sciences and Engineering Research Council (NSERC), and the Social Sciences and Humanities Research Council (SSHRC) – have been streamlined into a new harmonized talent program called the Canada Research Training Awards Suite (CRTAS) that will open for applications in summer 2025.

Automerization is defined as a rearrangement reaction that yields a degenerate form of the starting material. We now report that cyclohexeno[3,4]cyclodeca-1,5-diyne-3-ene rearranges to its automer, via a D2h-symmetric p-benzyne intermediate. The NMR evidence is that when the enediyne is heated to 75 °C in DMSO with either LiI or NaNO3 as possible nucleophile, the enediyne is consumed only in the presence of LiI, whereas it remains “unchanged” in the presence of NaNO3.

High-field dynamic nuclear polarization nuclear magnetic resonance (DNP NMR) spectroscopy transfers polarization from unpaired electrons in polarizing agents to nuclei of interest to boost NMR sensitivity. Verdazyl biradicals are a promising choice as polarizing agents because they have been found to generate narrower electron paramagnetic resonance (EPR) signals compared to nitroxide biradicals; an advantageous characteristic for high-field DNP when operating above 400 MHz/263 GHz. The use of verdazyl radicals as DNP polarizing agents has been very limited to date, yet, recent numerical simulations have predicted that verdazyl-nitroxide hybrid biradicals could be more effective polarizing agents than nitroxide-nitroxide biradicals. Herein, the syntheses of a series of verdazyl mono- and biradicals, as well as verdazyl-nitroxide biradicals are described. These radicals were examined in high-field DNP NMR experiments (600 MHz/395 GHz), by measuring 1H signal enhancements directly and through 13C{1H} cross-polarization experiments. X-band EPR, 1H DNP field profiles, and experiments to determine the nuclear build-up times were performed for verdazyl-nitroxide biradicals VerTEMPol and VerTEKol. These hybrid biradicals provide enhancements of up to 100-fold increased signal intensities (i.e., representing >104-fold time savings), approximately four times higher than that of the nitroxide biradical TEKPol, a commonly used polarizing agent in the field.

Chiral nanographenes are an intriguing class of polycyclic aromatic hydrocarbon structures, where combining the unique properties of inherently chiral…

A Sn-mediated mechanochemical reductive aromatization of 1,4-dihydroxy- and 1,4-dimethoxy-cyclohexadienes has been used to form 12 acenes, including derivatives of benzene, anthracene, tetracene, pent...