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A density functional theory (DFT) study has been performed to investigate the mechanism of ruthenium-catalyzed deoxygenative hydroboration of carboxylic acid. The reduction of the carbonyl motif is suggested to proceed via an intramolecular 1,3-hydride shift mechanism. The second HBpin coordination intermediate with the Ru center could facilitate the pinBOBpin reductive elimination and the PhCH2OBpin reductive elimination step. The energy span for the reaction is 25.2 kcal mol−1.

The reaction mechanisms of the hydrogenation of [(η5-C5H2-1,2,4-Me3)2Hf]2(NCO) (μ2-N) (1) were studied using density functional theory (DFT) method. The calculated results indicate that the first step is the addition of H2 to the Hf N double bond, the second step is the insertion of isocyanate into the bridging metal hydride. The metal centers with a low electronegativity benefits the hydrogenation of 1. Then the reaction mechanisms of allenes with 1 were also investigated. The calculated results imply that the allenes with larger hindrance tend to undergo 1,2 addition with 1, the allenes with smaller hindrance tend to undergo 2+2 cycloaddition with 1, which is in good agreement with experimental results.

The palladium-catalyzed oxidative borylation reaction of N-tosylhydrazones has been developed. The reaction features mild conditions, broad substrate scope, and good functional group tolerance. It thus represents a highly efficient and practical method for the synthesis of di-, tri-, and tetrasubstituted alkenylboronates from readily available N-tosylhydrazones. One-pot Suzuki coupling and other transformations highlight the synthetic utility of the approach. DFT calculations have revealed that palladium-carbene formation and subsequent boryl migratory insertion are the key steps in the catalytic cycle. The high stereoselectivity observed in the formation of trisubstituted alkenylboronates has been explained by distortion-interaction analysis and NBO analysis.

Shade avoidance syndrome enables shaded plants to grow and compete effectively against their neighbors. In Arabidopsis, the shade-induced de-phosphorylation of the transcription factor PIF7 (PHYTOCHROME-INTERACTING FACTOR 7) is the key event linking light perception to stem elongation. However, the mechanism through which phosphorylation regulates the activity of PIF7 is unclear. Here, we show that shade light induces the de-phosphorylation and nuclear accumulation of PIF7. Phosphorylation-resistant site mutations in PIF7 result in increased nuclear localization and shade-induced gene expression, and consequently augment hypocotyl elongation. PIF7 interacts with 14-3-3 proteins. Blocking the interaction between PIF7 and 14-3-3 proteins or reducing the expression of 14-3-3 proteins accelerates shade-induced nuclear localization and de-phosphorylation of PIF7, and enhances the shade phenotype. By contrast, the 14-3-3 overexpressing line displays an attenuated shade phenotype. These studies demonstrate a phosphorylation-dependent translocation of PIF7 when plants are in shade and a novel mechanism involving 14-3-3 proteins, mediated by the retention of PIF7 in the cytoplasm that suppresses the shade response.