An ad-hoc, yet widely adopted approach to investigate complex molecular objects in motion using importance-sampling schemes involves two steps, namely (i) mapping the multidimensional free-energy landscape that characterizes the movements in the molecular object at hand and (ii) finding the most probable transition path connecting basins of the free-energy hyperplane. To achieve this goal, we turn to an importance-sampling algorithm, coined well-tempered metadynamics-extended adaptive biasing force (WTM-eABF), aimed at mapping rugged free-energy landscapes, combined with a path-searching algorithm, which we call multidimensional lowest energy (MULE), to identify the underlying minimum free-energy pathway in the collective-variable space of interest. First, the well-tempered feature of the importance-sampling scheme confers to the latter an asymptotic convergence, while the overall algorithm inherits the advantage of high sampling efficiency of its predecessor, meta-eABF, making its performance less sensitive to user-defined parameters. Second, the Dijkstra algorithm implemented in MULE is able to identify with utmost efficiency a pathway that satisfies minimum free energy of activation among all the possible routes in the multidimensional free-energy landscape. Numerical simulations of three molecular assemblies indicate that association of WTM-eABF and MULE constitutes a reliable, efficient and robust approach for exploring coupled movements in complex molecular objects. On account of its ease of use and intrinsic performance, we expect WTM-eABF and MULE to become a tool of choice for both experts and nonexperts interested in the thermodynamics and the kinetics of processes relevant to chemistry and biology.

Because organoboron compounds readily undergo a diverse array of transformations and are widely used in various fields, the development of C-Bbond-forming reactions have attracted considerable attention. Herein we report a new method for forming C-B bonds by means of Cucatalyzed ring-opening/borylation reactions of cyclopropenes. This method provides efficient access to a new type of stable allylborane-Lewis base adduct, which is a versatile synthon. The configuration of the products can be well controlled with this method, and some of the configurations we obtained are inaccessible by means of other catalytic methods for generating allylborons. Mechanistic studies indicated that the reactions proceed via insertion of an alkenyl Cu carbene-generated in situ by cyclopropene ring opening-into the B-H bond; the ring-opening step determines both the rate and the stereochemistry.

A simple and efficient strategy of constructing ferrocene-based thioether ligands through metalfree reductive coupling of thiols with N-tosylhydrazones bearing a ferrocenyl group has been developed. This method features metal-free, good functional group tolerance, and readily available starting materials. Moreover, the compound 3k as a novel chemosensor has shown excellent recognition towards Hg 2+ ion via optical and electrochemical signals. Quantification of the absorption titration analysis shows that the detection limit was 9.56 × 10-7 M for 3k-Hg 2+ .

The allylnickel-catalyzed living coordination polymerization of allenylferrocene was compounded, two allenylferrocene derivatives (L-1 and D-1) bearing chiral amide pendants were designed and synthesized. The living coordination polymerization of L-1 and D-1 were afforded by the allynickel(II) complexes, which gave the polymer with controlled molecular weights and narrow molecular weight distribution in high yields. Three polyallenylferrocenes exhibited electrochemical properties. The helical structure was stable in the aprotic solvents observed through the circular dichroism spectra.