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NHC-mediated photocatalytic para-selective C–H acylation of aryl alcohols: regioselectivity control via remote radical spiro cyclization

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Science China Chemistry 2025年

作者： Tinglei Zhang Lala Wang Xiaolin Peng Tianhui Liao Dongmei Chen Ting Tu Donghan Liu Ziye Cheng Shiqing Huang Shi-Chao Ren Xinglong Zhang Yonggui robin Chi State Key Laboratory of green Pesticide Key Laboratory of Green Pesticide and Agricultural Bioengineering Ministry of Education Guizhou University Qiannan Medical College for Nationalities School of Chemistry Chemical Engineering and Biotechnology Nanyang Technological University Department of Chemistry The Chinese University of Hong Kong Institute of High Performance Computing Agency for Science Technology and Research

Friedel-Crafts reaction and transition-metal catalysis represent primary methodologies for arene acylation; however, suffer from certain limitations, such as electronic effect-dependent reactivity, regioselectivity issues, the necessity of directing group, and relatively exceptionally limited exploration in meta-and para-acylations. N-heterocyclic carbene(NHC) catalysis has recently emerged as a promising alternative strategy for arene acylation, offering distinct regioselectivity profiles that are challenging to achieve through known methods. Herein, an NHC-mediated photo-catalytic para-selective C–H acylation of aryl alcohols is disclosed. The reaction employs a remote radical-induced temporary spiro cyclization strategy, proceeding via tandem radical dearomatization, radical acylation, rearomatization processes. Combined experimental and computational mechanistic studies support the proposed reaction pathway and observe an exclusive para-selectivity regardless of the nature of the substituents on the substrates. Despite the less satisfactory yields, the current method exhibits non-electronic nature-based reactivity and regioselectivity, enabling quick access to acylated arenes that are difficult or impossible for reported methods.

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Optimal control of a hybrid microgrid for hydrogenbased heat supply using deep reinforcement learning

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Clean Energy 2023年第5期7卷 940-951页

作者： robin Heckmann Faculty of Computer Science University of Library Studies and Information Technologies119Tsarigradsko shosse Blvd1784SofiaBulgaria

green hydrogen is considered one of the key technologies of the energy transition,as it can be used to store surpluses from renewable energies in times of high solar radiation or wind speed for use in dark *** paper examines the decarbonization potential of hydrogen for the heating ***,99%of hydrogen is produced from fossil fuels,because hydrogen derived from renew-able energy sources remains prohibitively expensive compared with its conventional ***,due to the expansion of renewable energy sources and the current energy crisis of conventional energy sources,hydrogen from renewable energy sources is becoming more and more *** optimize the efficiency of green hydrogen production and make it more price-competitive,the author simulates a hydrogen production plant consisting of a photovoltaic plant,a power grid,hydrogen storage,an electro-lyser,a natural gas purchase option,a district heating plant and *** the deep deterministic policy gradient algorithm from deep reinforcement learning,the plant is designed to optimize itself by simulating different production scenarios and deriving *** connected district heating plant is used to map how hydrogen can be optimally used for heat supply.A demonstrable outcome of this paper is that the utilization of deep deterministic policy gradient,over the course of a full year,can result in a com-petitive production of hydrogen derived from renewable or stored energy sources for the heating industry as a natural gas substitute.

关键词： hydrogen renewable energy hybrid microgrid deep reinforcement learning deep deterministic policy gradient

N-heterocyclic carbene-catalyzed arene formation reactions

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Science China Chemistry 2022年第2期65卷 210-223页

作者： Tingting Li Zhichao Jin Yonggui robin Chi State Key Laboratory Breeding Base of green Pesticide and Agricultural Bioengineering Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationGuizhou UniversityGuiyang 550025China Division of Chemistry&Biological Chemistry School of Physical&Mathematical SciencesNanyang Technological UniversitySingapore 637371Singapore

N-heterocyclic carbene-catalyzed reactions for the formation of aromatic compounds are *** reactions are subdivided into 4 types based on their activation modes.A brief summary on the achievements and the challenges remaining in Nheterocyclic carbene(NHC)-catalyzed arene construction processes is provided at the end of this *** outlook into the future research direction within this field is also given based on our own opinion and knowledge on the trends of the development of NHC organocatalysis.

关键词： N-heterocyclic carbene arene construction cycloaddition organocatalysis

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Chiral boryl radical catalyzed asymmetric radical cycloisomerization

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Science China Chemistry 2024年第7期67卷 2121-2123页

作者： Jiamiao Jin Shi-Chao Ren Yonggui robin Chi National Key Laboratory of green Pesticide Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationGuizhou UniversityGuiyang 550025China School of Chemistry Chemical Engineeringand BiotechnologyNanyang Technological UniversitySingapore 637371Singapore

Asymmetric catalytic organic synthesis is of profound importance in modern research and industries,providing optically enriched molecules with diverse structures and functions[1].Enzymes,transition metal complexes,and simple organic molecules have all been found as powerful catalysts that enable the bond breaking and forming events with excellent control over stereo-selectivity *** the realm of designed small molecule organic catalysts.

关键词： radical catalyzed asymmetric

COMPLETE STREETS&LIVABLE CENTERSWhy Location Matters

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Journal of green Building 2011年第3期6卷 21-32页

作者： robin Holzer Zakcq Lockrem Citizens’Transportation Coalition(CTC) Asakura robinson Co.

INTRODUCTION In recent years,Houston has made great strides in green building,moving into the top ten nationally on both LEED certified and Energy Star rated *** the same time,fewer steps have been taken to address transportation,which accounts for one third of *** gas emissions.3 To achieve greater sustainability,architects,planners,and developers must take the space between buildings into greater account.

关键词： LEED ND complete streets livable centers activity centers density sustainable buildings sustainable transportation walkscore mapnificent greenTRIP greenhouse gas emissions walkability bikeability pedestrian access public transit

Alpine Taxa Exhibit Differing Responses to Climate Warming in the Snowy Mountains of Australia

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Journal of Mountain Science 2010年第2期7卷 167-175页

作者： K.green National Parks and Wildlife Service Snowy Mountains RegionPO Box 2228Jindabyne NSW 2627Australia

The phenologies of plants and animals in snow-covered landscapes are expected to accelerate with global ***,there are few studies that have examined a range of unrelated taxa in alpine environments to determine whether there is commonality in the proximate causes,synchrony in timing,or the direction of any *** for five alpine animal species and two alpine plant species,chosen primarily for their visibility,were examined to determine their temporal response to regional climate *** the 30-year period studied,they showed an array of different phenological *** flowering appeared linked to date of snow melt,whereas animal responses *** having accelerated phenologies,two migratory bird species exhibited contrary changes;one to low-altitude warming regardless of snow conditions in the alpine zone (flame robin) and the other to state of the snowpack regardless of low-altitude temperatures (Richard's pipit).By contrast,the migratory bogong moth arrived significantly later over the years with no apparent explanatory climatic *** bogong moths are not responding to earlier snow melt,insectivorous predators on the ground *** could lead to a serious mismatch in timing at different trophic levels,putting pressure on endangered *** of locally wintering insect species,March flies and Macleay's swallowtails,were not significantly related to measured climatic parameters over the study period.A consequence of the disparate responses to climate warming recorded here is the questionable value of 'indicator species' to examine the impact of climate warming on alpine ecosystems.

关键词： Bogong moth Climate change Migration Mismatch Phenology

Construction of Multi-Substituted Benzenes via NHC-Catalyzed Reactions of Carboxylic Esters

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Chinese Journal of Chemistry 2018年第4期36卷 333-337页

作者： Jichang Wu Chengli Mou Yonggui robin Chi Laboratory Breeding Base of green Pesticide and Agricultural Bioengi- neering Key Laboratory of Green Pesticide and Agricultural Bioengi- neering Ministry of Education Guizhou University Huaxi District Gui- yang Guizhou 550025 China School of Pharmacy Guiyang College of Traditional Chinese Medicine Huaxi District Guiyang Guizhou 550025 China

A carbene-catalyzed ester activation reaction for the synthesis of multi-substituted benzenes is developed. Tetra-substituted benzene com- pounds are efficiently synthesized through this methodology. Compared with aldehyde substrates used in previous reports, the ester substrates used here are much more readily available and inexpensive. In addition, the TEMPO oxidant used here is more inexpensive than the quinones commonly used in related carbene-catalyzed reactions.

关键词： N-heterocyclic carbene carboxylic ester benzene synthesis organocatalysis TEMPO oxidation

N-Heterocyclic Carbene Organocatalysis: Activation Modes and Typical Reactive Intermediates

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Chinese Journal of Chemistry 2020年第10期38卷 1167-1202页

作者： Xingkuan Chen Hongling Wang Zhichao Jin Yonggui robin Chi Department of Chemistry Jinan UniversityGuangzhouGuangdong 510632China Laboratory Breeding Base of green Pesticide and Agricultural Bioengineering Key Laboratory of Green Pesticide and Agricultural BioengineeringMinisry of EducationGuizhou UniversityHuaxi DistrictGuiyangGuizhou 550025China Division of Chemistry&Biological Chemistr School of Physical&Mathematical SciencesNanyang Technological UniversitySingopore 637371Singapore

N-Heterocyclic carbene(NHC)organocatalysis has been developed as an important approach in modern organic *** activation modes within NHC organocatalysis have been established with countless transformations being realized in both efficient and selective *** would like to provide an overview on the key progresses achieved within this field in the past two *** numerous excellent reviews have been documented within this area,we will mainly focus on the scientific development of this research field based on the basic reaction modes and typical reaction intermediates.

关键词： synthesis. catalysis Heterocyclic

Carbene-catalyzed activation of cyclopropylcarbaldehydes for mannich reaction andδ-lactam formation:remote enantioselecitvity control and dynamic kinetic asymmetric transformation

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Science China Chemistry 2021年第6期64卷 985-990页

作者： Jie Lv Jun Xu Xuling Pan Zhichao Jin Yonggui robin Chi State Key Laboratory Breeding Base of green Pesticide and Agricultural Bioengineering Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationGuizhou UniversityGuiyang 550025China School of Pharmacy Guizhou University of Traditional Chinese MedicineGuiyang 550025China Division of Chemistry&Biological Chemistry School of Physical&Mathematical SciencesNanyang Technological UniversitySingapore 637371Singapore

An N-heterocyclic carbene(NHC)-catalyzed enantioselective Mannich reaction of the remoteγ-carbon of cyclopropylcarbaldehydes is disclosed for the first ***-and enantiomerically enriched multicyclicδ-lactam compound is afforded as the main product from 8 possible stereo-specific isomers through dynamic kinetic asymmetric transformation(DYKAT)*** chiral functional molecules can be afforded from the lactam products through simple protocols with retentions of the optical purities.

关键词： N-heterocyclic carbene organocatalysis dynamic kinetic asymmetric transformation 1-cyclopropylcarbaldehydes asymmetric reactions