Search

Alkenylboronates are highly versatile building blocks and valuable reagents in the synthesis of complex molecules. Compared with that of monosubstituted alkenylboronates, the synthesis of multisubstituted alkenylboronates is challenging. The copper‐catalyzed carboboration of alkynes is an operationally simple and straightforward method for synthesizing bis/trisubstituted alkenylboronates. In this work, a series of copper‐metallized N‐Heterocyclic Carbene (NHC) ligand porous polymer catalysts are designed and synthesized in accordance with the mechanism of carboboration. By using CuCl@POL‐NHC‐Ph as the optimal nanocatalyst, this study realizes the β‐regio‐ and stereoselective (syn‐addition) 1,2‐carboboration of alkynes (regioselectivity up to >99:1) with satisfactory yields and a wide range of substrates. This work not only overcomes the selectivity of carboboration but also provides a new strategy for the design of nanocatalysts and their application in organic synthesis. [ABSTRACT FROM AUTHOR]

During the chlor-alkali process, in operation since the nineteenth century, electrolysis of sodium chloride solutions generates chlorine and sodium hydroxide that are both important for chemical manufacturing1–4. As the process is very energy intensive, with 4% of globally produced electricity (about 150 TWh) going to the chlor-alkali industry5–8, even modest efficiency improvements can deliver substantial cost and energy savings. A particular focus in this regard is the demanding chlorine evolution reaction, for which the state-of-the-art electrocatalyst is still the dimensionally stable anode developed decades ago9–11. New catalysts for the chlorine evolution reaction have been reported12,13, but they still mainly consist of noble metal14–18. Here we show that an organocatalyst with an amide functional group enables the chlorine evolution reaction; and that in the presence of CO2, it achieves a current density of 10 kA m−2 and a selectivity of 99.6% at an overpotential of only 89 mV and thus rivals the dimensionally stable anode. We find that reversible binding of CO2 to the amide nitrogen facilitates formation of a radical species that plays a critical role in Cl2 generation, and that might also prove useful in the context of Cl− batteries and organic synthesis19–21. Although organocatalysts are typically not considered promising for demanding electrochemical applications, this work demonstrates their broader potential and the opportunities they offer for developing industrially relevant new processes and exploring new electrochemical mechanisms.A study shows that an organocatalyst with an amide functional group, and carbon dioxide, can efficiently and selectively produce chlorine, potentially offering a low-cost and less energy intensive alternative to the chlor-alkali process. [ABSTRACT FROM AUTHOR]

James T.C. Liu, who was an international authority on the politics and history of China, particularly on the Sung dynasty, died in Lawrenceville, NJ, on Sep 30, 1993, aged 74. He served as a teacher in Chinese studies in the University of Pittsburgh, Stanford University and Princeton University and inspired the establishment of the Inter-University Program for Chinese Language Studies in Taipei, Taiwan. Liu performed the role of a cultural ambassador and worked to enhance the cultural exchanges between China and the US. He established his reputation as an eminent authority on Sung history with the publication of his book 'Reform in Sung China: Wang An-shih and His New Policies.'

In the mol-ecule of the title compound, C(14)H(9)ClF(3)NO(2), the aromatic rings are oriented at a dihedral angle of 66.49 (3)°. Intra-molecular C-H⋯F and C-H⋯O inter-actions result in the formation of one planar five- and one non-planar six-membered ring. In the crystal structure, inter-molecular N-H⋯O hydrogen bonds link the mol-ecules into chains.