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Chinese Journal of Structural Chemistry 1995年第4期14卷 272-276页

作者：杜大明孟继本等 DepartmentofChemistryandCentralLaboratory NankaiUn DepartmentofChemistryandCentr

The photocycloaddition of (4-methyl-7-coumarinyl) oxyacetic acid propanediol diester 1 (C_27H_24O_10) in chloroform produced a single product 2 characterized to be syn head-tail. Crystal structure of 2 has been determined by X-ray diffraction analysis. The crystal belongs to orthorhombic system, space group Pbca, with cell parameters a=10. 745(5), b= 13. 443(4), c=33. 358(9) A, V=4791 (5) A￣3, M_r=508. 49,Z= 8, D_c=1. 41 g/cm￣3, μ= 1. 015 cm￣-1, F(000)=1064. The final R=0. 065 for 1587 observed reflections. Compound 2 has a large ring resulted from [2+2] photocycloaddition. The four-member ring of 2 has poor coplanarity, the two diagonal atoms of four-member ring are above the least-squares plane, and another diagonal atom couple is below the least-squares plane, the deviations of two couples are approximately equal.

关键词： photocycloaddition coumarin derivative crystal structure

Construction of 3,9-diazatetraasteranes and 3,9-diazatetracyclododecanes by photocycloaddition reaction of 1,4-dihydropyridines:Experimental and theoretical investigation

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Chinese Chemical Letters 2023年第12期34卷 177-182页

作者： Runzhi Sun Xiuqing Song Shijie Wang Xiaokun Zhang Hong Yan Yeming Wang Faculty of Environment and Life Beijing University of TechnologyBejing 100124China Large-scale Instruments and Equipments Sharing Platform Beijing University of TechnologyBeijing 100124China Beijing Tide Pharmaceutical Co. Ltd.Beijing 100176China

A photocycloaddition reaction of ethyl 1,4-diaryl-1,4-dihydropyridine-3-carboxylate for the construction of 3,9-diazatetraasteranes(Pr)and 3,9-diazatetracyclododecanes(P2)is reported for the first *** types of reaction product clearly differ with solvent,regardless of the irradiation *** difference in Pi and P2 lies in the second step of the intramolecular[2+2]*** order to further investigate this phenomenon and gain a deeper understanding of the photochemical behavior of 1,4-dihydropyridines,DFT and TDDFT theoretical calculations are *** results provide a good explanation for the formation of 3,9-diazatetraasteranes and 3,9-diazatetracyclododecanes.

关键词： 1,4-Dihydropyridine photocycloaddition Theoretical investigation 3,9-Diazatetracyclododecanes

Supramolecular Template-Assisted Catalytic[2+2]photocycloaddition in Homogeneous Solution

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CCS Chemistry 2023年第3期5卷 633-640页

作者： Fang Wang Sha Bai Qing-Wen Zhu Zi-Hang Wei Ying-Feng Han Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education Xi’an Key Laboratory of Functional Supramolecular Structure and MaterialsCollege of Chemistry and Materials ScienceNorthwest UniversityXi’an 710127

Supramolecular interactions can help recognize and organize substrates around an enzyme’s active sites and subsequently assemble a new molecule in a certain *** by nature’s control of reactions,in this work we designed a template catalyst equipped with ditopic Au(I)–N-heterocyclic carbene(NHC)functional sites that direct olefin substrates into reactive geometries via collaboration of coordination-driven ***,this catalyst enables the realization of catalytic[2+2]photocycloadditions with as low as 2 mol%catalyst loading in homogeneous solution and the delivery of a series of cyclobutane derivatives with excellent conversions and *** success of gram-scale reactions further demonstrates the feasibility of this strategy,which lays a solid foundation for the large-scale preparation of cyclobutane derivatives in the future.

关键词： N-heterocyclic carbene supramolecular catalysis template synthesis photocycloaddition self-assembly

SYNTHESES OF AZETIDINES VIA photocycloaddition OF C=C TO C=N DOUBLE BONDS

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影像科学与光化学 1995年第3期 248-250页

作者： FENG JUN MING YANG-FU FAN MEI-GONG(Institute of Photographic Chemistry,the Chinese Academy of Sciemes,Beijing 100101,P.R.China)

ＳＹＮＴＨＥＳＥＳＯＦＡＺＥＴＩＤＩＮＥＳＶＩＡＰＨＯＴＯＣＹＣＬＯＡＤＤＩＴＩＯＮＯＦＣ＝ＣＴＯＣ＝ＮＤＯＵＢＬＥＢＯＮＤＳ￥ＳＹＮＴＨＥＳＥＳＯＦＡＺＥＴＩＤＩＮＥＳＶＩＡＰＨＯＴＯＣＹＣＬＯＡＤＤＩＴＩＯＮＯＦ... 详细信息

ＳＹＮＴＨＥＳＥＳＯＦＡＺＥＴＩＤＩＮＥＳＶＩＡＰＨＯＴＯＣＹＣＬＯＡＤＤＩＴＩＯＮＯＦＣ＝ＣＴＯＣ＝ＮＤＯＵＢＬＥＢＯＮＤＳ￥ＳＹＮＴＨＥＳＥＳＯＦＡＺＥＴＩＤＩＮＥＳＶＩＡＰＨＯＴＯＣＹＣＬＯＡＤＤＩＴＩＯＮＯＦＣ＝ＣＴＯＣ＝ＮＤＯＵＢＬＥＢＯＮ...

关键词： azauracil photocycloaddition regioselectivity

Theoretical Studies on photocycloaddition Reactions of Oxazolines: Mechanism and Enantioselective Selectivities

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Theoretical Studies on Photocycloaddition Reactions of Oxazo...

Asymmetric reversible structural switching of a diene coordination polymer promoted by UV-visible light

第十三届全国量子化学会议

作者： Chun-Xiang Li Wei-Hai Fang Ganglong Cui Key Laboratory of Theoretical and Computational Photochemistry Ministry of EducationCollege of ChemistryBeijing Normal University

Oxazolines are found to exhibit enantioselective [4+2] and [4+4] photocycloaddition reactions in synthesizing polyheterocyclic ketones;but, the atomistic reaction mechanism remains unclear. In this work, we have employed high-level electronic structure methods such as DFT,CASSCF, and CASPT2 to explore [4+2] and [4+4] photocyclization reaction pathways of a typical oxazoline as well as its relevant photophysics. We have found that oxazoline first undergo excited-state intramolecular proton transfer(ESIPT) to generate four related excited-state *** have also found that in the T state, [4+2] photocycloaddition reaction has the lowest barrier(1.4kcal/mol) in exo-out conformer(thus dominate);while, exo-in conformer hold the dominant position in [4+4] photocycloaddition reaction with a barrier of 1.7 kcal/mol. In the T state, the C atom of the oxole moiety first attacks the N6 atom of the aniline moiety, followed by a T-> S intersystem crossing process to the S state. Subsequently, the second C-C bond is formed in the S state. Our present computational results not only rationalize available experiments but also provide new mechanistic insights.

关键词： Enantioselective ESIPT photocycloaddition

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Science China Chemistry 2024年第2期67卷 536-541页

作者： Yong Wang Qiaoqiao Zhang Yong-Yong Cao Qi Liu Brendan F.Abrahams Jian-Ping Lang College of Chemistry Chemical Engineering and MaterialsSoochow UniversitySuzhou215123China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032China College of Biological Chemical Science and EngineeringJiaxing UniversityJiaxing314001China School of Chemistry University of MelbourneVictoria3010Australia

In natural and artificial systems,reversible reactions are commonly asymmetric with respect to the time scale and nature of the stimuli which drive the forward and backward *** applications for which switching behavior is required,it is desirable that the reversible reaction goes as close to symmetric as possible;however,such systems are ***,we report an example of ultraviolet(UV)-visible light-regulated asymmetric reversible structural switching involving a diene-based coordination polymer,CP1 and its monocyclobutane product,*** is possible to cycle at least ten times through a forward [2+2] photocycloaddition reaction and the reverse,photocleavage reaction.A single cycle can be completed within a few *** transformation is accompanied by fast and distinct fluorescence changes,arising from optimisation of the reaction *** functional theory calculations allow rationalisation of the asymmetric reversible transformation between CP1 and CP1a rather than between CP1 and its dicyclobutane product *** work provides a clear illustration of reversible structural switching which approaches symmetric behaviour with respect to reaction rate and *** insights gained from this work also assist in the design of fast,reversible switching materials.

关键词： asymmetrical reversible structural switching coordination polymer photocycloaddition UV-visible light-controlled fluorescence switching

Synthesis of novel chalcone derivatives and their stabilization effect of spiropyran in PMMA films

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Chinese Chemical Letters 2011年第9期22卷 1025-1028页

作者： Zheng Kai Si Qing Zhang Min Zhao Xue Yuan Yuan Zhu Liang Ming Qiao Rong Sheng Yan Gang Liu School of Chemistry and Chemical Engineering Shanghai Jiaotong University Shanghai 200240 China

Three novel bis-chalcone derivatives with different alkyldioxy spacers were synthesized and dispersed into polymethyl methacrylate （PMMA） chloroform solution with 6-nitro-1＇-ethyl-3＇,3＇-dimethylspiro-2H-1-benzopyran-2,U-indoline （ESP） to prepare photochromic PMMA films in a facile way. After irradiation with 365 nm UV light, the photocrosslinking reaction between chalcone units was proved to retard the decolorization of merocyanine form of the photochromic spiropyran effectively, as results of the steric hindrance produced by photocycloaddition of chalcone groups. It has been found that the bis-chalcone molecule with the shortest spacer has the most effective stabilizing effect on retardation of decoloration of spiropyran. reserved.

关键词： Photochromism Chalcone Spiropyran photocycloaddition Slabilization effect

Yonarolide A, an unprecedented furanobutenolide-containing norcembranoid derivative formed by photoinduced intramolecular[2+2] cycloaddition

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Chinese Chemical Letters 2023年第2期34卷 420-424页

作者： Yeqing Du Ligong Yao Xuwen Li Yuewei Guo School of Chinese Materia Medica Nanjing University of Chinese MedicineNanjing 210023China State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China Drug Discovery Shandong Laboratory Bohai Rim Advanced Research Institute for Drug DiscoveryYantai 264117China

Eight polycyclic furanobutenolide-containing norcembrane diterpenoids featuring C19 frameworks(1–8)were rapidly recognized and isolated from the Hainan soft coral Sinularia sp. by the HSQC-based small molecule accurate recognition technology. Yonarolide A(1a), featuring an unprecedented 5/6/4/4/7 pentacyclic ring skeleton, was surprisingly obtained as a transformed product by leaving compound 1 under indoor natural light, and was further proved to be a [2 + 2] cycloaddition product of 1 by photochemical reaction. The absolute stereochemistry of 1a and the three known norcembrane diterpenoids 1, 4, and7 were determined by using X-ray diffraction(XRD) analyses. Further, with the aid of XRD analysis, the structure of scabrolide B(2), which was previously reported of possessing 5/6/7 tricyclic skeleton, was firmly revised as 2a with the rare inelegane skeleton featured by the highly oxygenated 5/7/6 tricyclic carbocycle.

关键词： Soft coral Sinularia Norcembranoid photocycloaddition SMART method

THE CRYSTALLOGRAPHIC STRUCTURE OF THE PHOTOOXIDIZED PRODUCT OF HYPOCRELLIN A AND THE STUDY OF THE PHOTODYNAMIC ACTION MECHANISM

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Science China Chemistry 1990年第6期33卷 649-655页

作者：梁丽竺迺珏蒋丽金 Institute of Biophysics Academia Sinica Beijing 100080 PRC Institute of Chemistry Academia Sinica Beijing 100080 PRC Institute of photographic Chemistry Academia Sinica Beijing 100012 PRC

In attempting to study the phototherapeutic action and the photosensitized oxygenation mechanism, we have determined the crystal structure of the main oxidized product of hypocrellin A (HA). It was crystallized in monoclinic system with space group P2_1. The cell data are: a=10.030(3), b=8.877(3), c=15.764(5), β=104.50(2)°, Z=2. The crystal structure has been determined by direct method and refined to a final R of 0.055 based on the 1408 observed reflections with l>2.5σ(Ⅰ). The photooxidized product is composed of a heptacyclic aliphatic hydrocarbon connecting with two α-naphthoquinone derivatives as its skeletal molecule. No peroxidic linkage has been found. On the basis of the crystal structure determined, we have deduced part of the process of formation of the oxide, ⅰ. e. firstly, the peroxide was formed by photocycloaddition of oxygen molecule to Hypocrellin A, then thermodissociation took place to form a stable oxide.

关键词： Hypocrellin A photosensitizer Hypocrellin A oxide (2+2) photocycloaddition X-ray crystal structure.

Reactions of Benzo[b]cyclobuta[d]pyran-3-one Derivatives with Sulfur Ylide

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复旦学报(自然科学版) 2005年第5期 285-286页

作者： Masayuki Yamashita,Yadav Navnath D.,Masaki Nagahama,Tomoki Inaba,Ikuo Kawasaki,Shunsaku Ohta Kyoto Pharmaceutical University Misasagi-Nakauchicho 5 Yamashinaku Kyoto 607-8414 Japan Kyoto Pharmaceutical University Misasagi-Nakauchicho 5 Yamashinaku Kyoto 607-8414 Japan Kyoto Pharmaceutical University Misasagi-Nakauchicho 5 Yamashinaku Kyoto 607-8414 Japan Kyoto Pharmaceutical University Misasagi-Nakauchicho 5 Yamashinaku Kyoto 607-8414 Japan Kyoto Pharmaceutical University Misasagi-Nakauchicho 5 Yamashinaku Kyoto 607-8414 Japan Kyoto Pharmaceutical University Misasagi-Nakauchicho 5 Yamashinaku Kyoto 607-8414 Japan