Intermolecular Ritter-type C–H amination of unactivated sp3 carbons has been developed. This new reaction proceeds under mild conditions using readily available reagents and an inexpensive source of nitrogen (acetonitrile). A broad scope of substrates can be aminated with this method since many functional groups are tolerated. This reaction also allows for the direct, innate C–H amination of a variety of hydrocarbons such as cyclohexane without the need of prefunctionalization or installation of a directing group.

The defense system of a plant can be primed for increased defense, resulting in an augmented stress resistance and/or tolerance. Priming can be triggered by biotic and abiotic stimuli, as well as by chemicals such as β-aminobutyric acid (BABA), a nonprotein amino acid considered so far a xenobiotic. Since the perception mechanism of BABA has been recently identified in Arabidopsis thaliana, in the present study we explored the possibility that plants do synthesize BABA. After developing a reliable method to detect and quantify BABA in plant tissues, and unequivocally separate it from its two isomers α- and γ-aminobutyric acid, we measured BABA levels in stressed and nonstressed A. thaliana plants, and in different plant species. We show that BABA is a natural product of plants and that the endogenous levels of BABA increase rapidly after infection with necrotrophic, biotrophic and hemibiotrophic pathogens, as well as after salt stress and submergence. Our results place the rise in endogenous BABA levels to a point of convergence in plant stress response and provide biological significance to the presence of a receptor in plants. These findings can explain the extremely widespread efficacy of BABA and open the way to unravel the early steps of priming.

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The copper-photocatalyzed borylation of aryl, heteroaryl, vinyl and alkyl halides( Ia nd Br) was reported. The reaction proceededu sing an ew heteroleptic Cu complex under irradiation with blue LEDs, givingt he corresponding boronic-acid esters in good to excellent yields. The reactionw as extended to continuous-flowc onditions to allow an easy scale-up. The mechanism of the reaction was studied and am echanism based on ar eductive quenching (Cu I /Cu I */Cu 0 )w as suggested.

An improved version of the BIRD-HMBC experiment is proposed. In comparison to the original version, the filtering (suppression of (1) J(CH) signals) is accomplished using a double tuned G-BIRD filter positioned in the middle of the long-range correlations evolution period. Compensation of offset dependence by replacing the rectangular 180 degree pulses with the broadband inversion pulses (BIPs), with superior inversion performance and improved tolerance to B(1) field inhomogeneity, significantly improves the sensitivity of the original BIRD-HMBC experiment. For usual one-bond coupling constants ranges (115-180 Hz), optimal results are easily obtained by adjusting the delays, delta, of the BIRD elements to an average J value. For larger ranges (e.g. 110-260 Hz), the use of a double tuned G-BIRD filter allows excellent suppression degrees for all types of one-bond constants present in a molecule, superior to the original scheme and other purging schemes. These attributes make the improved version of the BIRD-HMBC experiment a valuable and robust tool for rapid spectral analysis and rapid checks of molecular skeletons with a minimum spectrometer time.