Total Syntheses of Cinchona Alkaloids via Photoredox-Catalyzed Deoxygenative Arylation.

Metallaphotoredox-enabled deoxygenative arylation of alcohols is a recently developed robust synthetic strategy for sp2-sp3 coupling by MacMillan. Inspired by this method, we report herein its first utilization in natural product total synthesis through realizing the coupling of 4-bromo-quinoline or 4-bromo-6-methoxyquinoline with quincorine or quincoridine, respectively. The alcohols were de novo synthesized in racemic form by a key step of the intramolecular Diels-Alder reaction or in an enantioselective manner by Ir/amine dual-catalyzed allylation. All members of the cinchona alkaloids could be prepared efficiently.

[Double-column Die-punch fractures of distal radius treated with butterfly plate fixation via Henry approach].

OBJECTIVE: To explore clinical effect of open reduction and internal fixation with Henry's approach butterfly plate in treating double-column Die-punch fractures of distal radius. METHODS: From January 2018 to June 2021, 26 patients with double-column Die-column distal radius were treated with open reduction and internal fixation through Henry's surgical approach and using distal radius volar column plate(butterfly plate), including 14 males and 12 females, aged from 20 to 75 years old with an average age of (44.2±3.4) years old. Postopertaive complications were observed, Gartland-Werley score at 12 months after opertaion was used to evaluate wrist joint function. RESULTS: All 26 patients were followed up from 10 to 18 months with an average of(13.4±0.8) months. All fractures were obtained fracture union, the time ranged from 8.5 to 15.8 weeks with an average of (11.4±0.5) weeks. All incisions healed at stageⅠwithout infection, nerve injury and internal fixation failure occurred. Postoperative Gartland-Werley score at 12 months was (3.65±0.36), and 16 patients got excellent result, 8 good and 2 moderate. CONCLUSION: Open reduction and internal fixation with butterfly plate for the treatment of double-column Die-punch fractures of the distal radius through volar Henry approach could obtain satisfactory clinical outcomes.

Cathodized copper porphyrin metal-organic framework nanosheets for selective formate and acetate production from CO2 electroreduction.

An efficient and selective Cu catalyst for CO2 electroreduction is highly desirable since current catalysts suffer from poor selectivity towards a series of products, such as alkenes, alcohols, and carboxylic acids. Here, we used copper(ii) paddle wheel cluster-based porphyrinic metal-organic framework (MOF) nanosheets for electrocatalytic CO2 reduction and compared them with CuO, Cu2O, Cu, a porphyrin-Cu(ii) complex and a CuO/complex composite. Among them, the cathodized Cu-MOF nanosheets exhibit significant activity for formate production with a faradaic efficiency (FE) of 68.4% at a potential of -1.55 V versus Ag/Ag+. Moreover, the C-C coupling product acetate is generated from the same catalyst together with formate at a wide voltage range of -1.40 V to -1.65 V with the total liquid product FE from 38.8% to 85.2%. High selectivity and activity are closely related to the cathodized restructuring of Cu-MOF nanosheets. With the combination of X-ray diffraction, X-ray photoelectron spectroscopy, high resolution transmission electron microscopy and Fourier transform infrared spectroscopy, we find that Cu(ii) carboxylate nodes possibly change to CuO, Cu2O and Cu4O3, which significantly catalyze CO2 to formate and acetate with synergistic enhancement from the porphyrin-Cu(ii) complex. This intriguing phenomenon provides a new opportunity for the rational design of high-performance Cu catalysts from pre-designed MOFs.