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Science China Chemistry 2020年第1期63卷 11-15页

作者： Wei Ou pei-Qiang huang Department of Chemistry Fujian Provincial Key Laboratory of Chemical Biology College of Chemistry and Chemical Engineering Xiamen University

Aldehydes are perhaps the most versatile compounds that enable many C-C bond forming reactions,which are not amenable for other subclasses of carbonyl *** report the first use of amides as surrogates of aldehydes for C-C bond formation,namely,the direct Knoevenagel-type condensation based on *** one-pot method consists of controlled reduction of an amide with LDBIPA[LiAlH(iBu)2(OiPr)],Lewis acid-mediated release of a reactive iminium ion intermediate,nucleophilic addition,and in situ elimination of *** reaction shows good functional group *** also demonstrated that the Schwartz reagent could be used as an alternative of *** employment of nitromethane and a silyl enol ether as the nucleophiles opens an avenue for the unprecedented amide-based nitro-aldol condensation reaction and aldol condensation reaction,respectively.

关键词： amides Knoevenagel condensation C–C bond formation one-pot reaction amide transformation

Efficient Degradation of Cellulose in Its Homogeneously Aqueous Solution over 3D Metal-Organic Framework/Graphene Hydrogel Catalyst

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Chinese Journal of Chemical Physics 2016年第6期29卷 742-748,I0002页

作者： pei huang Li-feng Yan DepartmentofChemicalPhysics iCHEMUniversityoFScienceandTechnologyofChinaHefei230026China

Catalytic degradation of cellulose to chemicals is an attracting topic today for the conver- sion of biomass, and the development of novel catalysts is a key point. Since metal-organic frameworks （MOFs） possess uniform, continuous, and permeable channels, they are valu- able candidate as catalysts. Here, a new 3D MOF/graphene catalyst was prepared by in situ growth of the zeolitic imidazolate frameworks （ZIF-8） nanoparticles inside the pore of an as-formed 3D reduced graphene oxide （rGO） hydrogel. The ZIF-8/rGO nanocomposite owns both micropores and mesopores with large specific surface area and plenty of acids sites, which is an idea catalyst for biomass degradation. Cellulose was dissolved in allmline aqueous solution at first, and then it was degraded efficiently over the new catalyst under hydrothermal condition. The conversion reaches 100% while the main products are formic acid with a maximum yield of 93.66%. In addition, the catalyst can be reused with high activity.

关键词： Graphene Metal-Organic framework Cellulose Catalyst Formic acid

Approach to conceptual data integration for multidimensional data analysis in e-commerce

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Journal of Systems Engineering and Electronics 2006年第3期17卷 635-641页

作者： Zhang Zhe huang pei School of Management Fudan Univ. Shanghai 200433P. R. China School of Management Shanghai Jiaotong Univ. Shanghai 200052 P. R. China

In e-commerce the multidimensional data analysis based on the Web data needs integrating various data sources such as XML data and relational data on the conceptual level. A conceptual data description approach to multidimensional data model the UML galaxy diagram is presented in order to conduct multidimensional data analysis for multiple subjects. The approach is illuminated using a case of 2_roots UML galaxy diagram that takes marketing analysis of TV products involved one retailer and several suppliers into consideration.

关键词： conceptual data integration multidimensional data analysis e-commerce

Precise integration method for a class of singular two-point boundary value problems

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Acta Mechanica Sinica 2013年第2期29卷 233-240页

作者： Wen-Zhi Zhang pei-Yan huang School of Civil and Transportation Engineering South China University of Technology

In this paper we present a precise integration method based on high order multiple perturbation method and reduction method for solving a class of singular twopoint boundary value ***,by employing the method of variable coefficient dimensional expanding,the non-homogeneous ordinary differential equations（ODEs） are transformed into homogeneous *** the interval is divided evenly,and the transfer matrix in every subinterval is worked out using the high order multiple perturbation method,and a set of algebraic equations is given in the form of matrix by the precise integration relation for each segment,which is worked out by the reduction *** numerical examples are elaboratedd to validate the present method.

关键词： Singular two point boundary value problem Precise integration method High order multiple perturbation method Reduction method

Ketone Synthesis by Direct, Orthogonal Chemoselective Hydroacylation of Alkenes with Amides: Use of Alkenes as Surrogates of Alkyl Carbanions

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Chinese Journal of Chemistry 2019年第8期37卷 811-816页

作者： Hui Geng pei-Qiang huang Department of Chemistry Fujian Provincial Key Laboratory of Chemical BiologyCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamenFujian 361005China

Summary of main observation and conclusion Direct functionalization of alkenes and direct transformation of carboxamides are two exciting areas that have attracted considerable attention in recent *** report herein that secondary amides,the least reactive derivatives of carbonyl compounds,upon activated with triflic anhydride,can serve as effective hydroacylating reagents in partner with alkenes to yield ketones at ambient *** method was applied to the one-step synthesis of racemic *** this method,alkenes serve as surrogates of organometallic reagents,which allows the orthogonal chemoselective *** ready availability of many olefins such as camphene and norbornene permits one-step ketone synthesis that would require several steps by conventional methods.

关键词： Alkenes Amides Alkyl Carbanions

Catalytic diastereoselective and enantioconvergent C(sp^3)–C(sp^3) cross-coupling of racemic partners

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Science China Chemistry 2020年第7期63卷 871-872页

作者： Ai-E Wang pei-Qiang huang Department of Chemistry and Fujian Provincial Key Laboratory of Chemical Biology College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China

Carbon-carbon bond formation is the core of organic *** metal-catalyzed cross-coupling reaction between organohalides and organometallic reagents is one of the most important and straightforward methods for construction of C-C *** catalytic cross coupling between two sp^2-carbon centers,e.g.,aryl-aryl crosscouplings,has become a routine transformation in laboratories and industrial processes for synthesis of drugs and fine ***-catalyzed cross-coupling between two sp'-carbon centers(Figure 1(a)).

关键词： synthesis. coupling centers

Overview of Computational Modeling in Nano/Micro Scaled Thin Films Mechanical Properties and Its Applications

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Computer Modeling in Engineering & Sciences 2019年第8期120卷 239-260页

作者： Chang-Chun Lee pei-Chen huang Department of Power Mechanical Engineering National Tsing Hua UniversityNo.101Section 2Kuang-Fu RoadHsinchu 30013Taiwan

This research reviews the application of computational mechanics on the properties of nano/micro scaled thin films,in which the application of different computational methods is *** concept and fundamental theories of concerned applications,material behavior estimations,interfacial delamination behavior,strain engineering,and multilevel modeling are thoroughly ***,an example of an interfacial adhesion estimation is presented to systematically estimate the related mechanical reliability issue in the microelectronic *** presented results show that the peeled mode fracture is the dominant delamination behavior of layered material system,with high stiffness along the bonding ***,the shear mode fracture being dominated as the polymer cover plate with low moduli is *** occurrence of crack advance is also significantly influenced by the interfacial crack length and applied ***,this paper could serve as a guideline of several engineering cases with the assistance of computational mechanics.

关键词： Computational mechanics mechanical responses nano/micro thin films

Concise,enantioselective total syntheses of both the proposed and revised structures of (-)-versiquinazoline H

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Chinese Chemical Letters 2020年第1期31卷 61-63页

作者： Jiang-Feng Wu pei-Qiang huang Department of Chemistry Fujian Provincial Key Laboratory of Chemical BiologyCollege of Chemistry and Chemical EngineeringXiamen University

The enantioselective total synthesis of the putative structure of versiquinazoline H and three diastereomers has been achieved,which allowed the revision of the stereochemistry of this natural *** six-step total synthesis relied on the evolution of the strategy that we previously developed,which features a DMDO-triggered tandem *** modification of the lactamization step resulted in a significant improvement of yield that ensured the efficient total synthesis.

关键词： Alkaloids Total synthesis Tandem reaction Structural revision Protecting group-free

Enantioselective total syntheses of marine natural products(+)-cylindricines C,D,E and their diastereomers

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Organic Chemistry Frontiers 2022年第1期9卷 58-63页

作者： Ying-Hong huang Zhan-Jiang Liu pei-Qiang huang Department of Chemistry Fujian Provincial Key Laboratory of Chemical BiologyCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamenFujian 361005P.R.China

A seven-step total synthesis of(+)-cylindricine D and epi-cylindricine D is *** efficiency relies on the highly diastereoselective reductive bis-functionalization of N,O-protected(S)-pyroglutaminol by our recently improved protocol to build the N-α-tert-alkylamine motif,and a telescoped one-step fourreaction protocol to build the fused bicyclic ring system.(+)-Cylindricine C and its 2-epimer were synthesized by essentially the same sequence in eight *** of the latter then delivered(+)-cylindricine E and its 2-epimer,respectively.

关键词： latter steps essentially

Cross-Coupling of Secondary Amides with Tertiary Amides: The Use of Tertiary Amides as Surrogates of Alkyl Carbanions for Ketone Synthesis

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Chinese Journal of Chemistry 2019年第9期37卷 887-891页

作者： Shu-Ren Wang pei-Qiang huang Department of Chemistry Fujian Provincial Key Laboratory of Chemical BiologyCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamenFujian 361005China

In recent years,exciting progress has been made in the field of direct transformation of amides,nevertheless,the condensation between two amides remains rare and restricted to homo-coupling ***,we report the cross-coupling of secondary amides with tertiary amides,which provides a synthesis of ketones under mild conditions,and features the use of tertiary amides as surrogates of alkyl *** method relies on the coupling of enamines,generated from tertiary amides by catalytic partial reduction of tertiary amides with Vaska's catalyst,with nitrilium ions,formed in situ from secondary amides via activation with trifluoromethanesulfonic anhydride,and on the subsequent deformylation.

关键词： Secondary Amides Tertiary Amides Alkyl Carbanions