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Chemical Research in Chinese Universities 2014年第6期30卷 1051-1056页

作者： LU Taotao NIE Junqi CHEN Zuxing YANG Guichun LU Cuifen Hubei Collaborative Innovation Center for Advanced Organochemical Materials Key Laboratory for the Synthesis and Application of Organic Functional Molecules Ministry of Education Hubei University Wuhan 430062 P. R. China

The asymmetric alkylation reactions induced by non-cross-linked polystyrene supported cyclosulfamide chiral auxiliary occurred in moderate to good yields with a very high stereoselectivity（e.e.〉99%）. Compared to non-supported cyclosulfamide chiral auxiliary, this chiral auxiliary can be recovered by simple precipitation and filtration, and could be reused at least four cycles without appreciable reduction in the yield or stereoselectivity.

关键词： Polystyrene Cyclosulfarnide chiral auxiliary Alkylation reaction

Optically Active chiral auxiliary Benzyloxyphenylglycinol for Preparation of Oxazolidine and Its Derivatives

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Chemical Research in Chinese Universities 2005年第4期21卷 476-479页

作者： FUYing-huan CHENJin WUTong-hao BAIXu TheCenterforCombinatorialChemistryandDrugDiscovery JilinUniversityChangchun130012P.R.China

To investigate the recovery of amino alcohols as chiral auxiliaries, optically active p-benzyloxyphenylglycinol and its corresponding oxazolidine of 1-naphthylcarboxaldehyde were prepared. Grignard additions to the oxazolidine followed by electrophilic quench and acidic hydrolysis afforded an aldehyde(compound 8)(later it was reduced to an alcohol, compound 9) in an excellent enantiomeric excess and a good recovery of the chiral amino alcohol. This research provides a model study of chiral amino alcohols in solid phase asymmetric synthesis.

关键词： chiral auxiliary p-Benzyloxyphenylglycinol Grignard addition Oxazolidine Asymmetric synthesis

Diastereoselective synthesis of(1S)-trans-cyclopropane-1,2-dicarboxylic acid derivatives using 1,2 4,5-di-O-isopropylidene-D-fructopyranose as the chiral auxiliary

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Journal of Chinese Pharmaceutical Sciences 2009年第1期18卷 30-32页

作者：李云锋孟祥豹李庆李中军北京大学天然药物及仿生药物国家重点实验室药学院化学生物学系北京100191

A new procedure for the highly diastereoselective synthesis of （1S）-trans-cyclopropane derivatives using a fructose derivative as the chiral auxiliary was developed. Chloroacetylated 1,2;4,5-di-O-isopropylidene-D-fructopyranose was reacted with a tertiary amine to form the ammonium salt, which was treated with cesium carbonate to give the cyclopropane derivative through ylide intermediate. The described procedure provides an efficient method to synthesize optically pure dior poly-substituded cyclopropanes.

关键词： chiral auxiliary Sugar Asymmetric synthesis Cyclopropanation

Scalable Cu(Ⅱ)-mediated intramolecular dehydrogenative phenol-phenol coupling:Concise synthesis of enantiopure axially chiral homo-and hetero-diphenols

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Chinese Chemical Letters 2021年第1期32卷 380-384页

作者： Yuefei Gu Tianyang Wang Ming Gao Zhu-Jun Yao State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

An intramolecular dehydrogenative homo-and hetero-coupling of phenols has been successfully developed for quick preparation of enantiopure axial diphenols under mild Cu(Ⅱ)-mediated conditions,using((4 S,5 S)-2,2-dimethyl-1,3-dioxolane-4,5-diyl)dimethanol as the chiral *** commercially available(R)-α-met hylbenzy la mine was identified as the best amine ligand for Cu(Ⅱ) in the reactions.A variety of homo/hetero bis-dihydroxylbenzoate substrates were examined,affording the corresponding axially chiral diphenols with satis factory to excellent diastereomeric ratios,and a representative scalable preparation was also attempted.A formal synthesis of natural product(+)-deoxyschizandrin has been achieved in this work using one axially chiral diphenol as the synthetic intermediate.

关键词： Axially chirality Dehydrogenative phenol-phenol coupling Cu(Ⅱ)-mediated oxidation chiral auxiliary Diastereoselectivity

Diastereoselective Epoxidation of N-Enoylsultams with Different chiral Sultams as Auxiliaries

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Chinese Journal of Chemistry 2006年第5期24卷 681-688页

作者：张殊佳陈永康李慧明黄维扬 ROGATCHOV, Viktor METZ, Peter College of Environment and Chemical Engineering Dalian University Dalian Liaoning 116622 China Department of Chemistry Hong Kong Baptist University Kowloon Tong Hong Kong China Institut für Organische Chemie Technische Universitat Dresden D-01069 Dresden Germany

Asymmetric epoxidation of N-enoylsultams （1, 3-15） incorporating a variety of chiral sultams as the chiral induction elements with UHP/TFAA has been studied. Both diastereomeric isomers of epoxides （2, 16-28） were... 详细信息

关键词： asymmetric epoxidation chiral auxiliary enoylsultam synthesis

Scope and Limitations of Optical Pure Hydantoins as chiral Auxiliaries in Asymmetric Mannich Reactions

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Chemical Research in Chinese Universities 2016年第2期32卷 219-225页

作者： CHEN Feng LU Cuifen NIE Junqi CHEN Zuxing YANG Guichun Hubei Collaborative Innovation Center for Advanced Organochemical Materials & Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules Hubei University Wuhan 430062 P. R. China

The Mannich reaction of various 5-substituted and N-acyl substituted chiral hydantoins with a series of aldimines smoothly occurred with full stereochemical control. These Mannich adducts have been cleaved by alcoholysis to afford several synthetically useful chiral building blocks like β-amino esters and β-lactams in good yields and in enantiopure form.

关键词： Scope Limitation Hydantoin chiral auxiliary Mannich reaction

A Concise,Practical chiral Resolution Approach of Racemic (E)-4,4-Dimethyl-1-(4-nitrophenyl) pent-1-en-3-ol to Its both Enantiomers via Strategy of Diastereomeric Ester Formation and Crystallization Using both N-Boc-D- and N-Boc-L-phenylglycines as chiral Auxiliaries

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Chemical Research in Chinese Universities 2024年第6期40卷 1096-1105页

作者： JIANG Shanshan YUAN Jia QIN Yanlan LUO Ying JIN Zhengsheng ZHAO Guilong TI Huihui School of Chinese Materia Medica Guangdong Pharmaceutical UniversityGuangzhou 510006P.R.China Zhongshan Institute for Drug Discovery Shanghai Institute of Materia MedicaChinese Academy of SciencesZhongshan 528400P.R.China Shanghai Institute of Materia Medica Chinese Academy of SciencesShanghai 201203P.R.China School of Chemistry and Chemical Engineering Guangdong Pharmaceutical UniversityGuangzhou 510006P.R.China

chiral secondary alcohols are an important class of functionalities commonly seen in drugs and other bioactive *** an ongoing drug discovery program in our laboratories,a nitro-bearing racemic allylic secondary alcohol (±)-1 was discovered as a promising drug candidate,and in the following preclinical studies,a concise,reliable,practical synthetic approach to its both enantiomers with high optical purities was greatly *** the present study,we developed a chiral resolution approach of (±)-1 to its both enantiomers,i.e.,(+)-1 and (-)-1,via the strategy of diastereomeric ester formation and crystallization using both N-Boc-D- and N-Boc-L-phenylglycines as chiral *** absolute configurations of all the four key intermediates were unambiguously determined by single-crystal X-ray diffraction,providing a solid foundation for the stereochemistry of the present *** two enantiomers were obtained in high optical *** approach is characterized by scalability and practicality and is envisaged to enable the chiral resolution of other racemic secondary alcohols,especially those with labile groups,such as NO_(2);olefinic C=C bond.

关键词： chiral resolution Phenylglycine chiral auxiliary chiral secondary alcohol Diastereomeric ester formation

Asymmetric Synthesis of All Four Isomers of an Unusual Heterocycle-Containing Amino Acid ： 2-Amino-3-furan-2-yl-pentanoic Acid

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Chinese Journal of Chemistry 2012年第2期30卷 460-465页

作者： Nie,Lei Yang,Rui Zhang,Conghai Yin,Haichuan Yan,Shengjiao Lin,Jun Key Laboratory of Medicinal Chemistry for Natural Resource School of Chemical Science and TechnologyYunnan UniversityKunmingYunnan 650091China The Education Department of Yunnan Province KunmingYunnan 650091China

All four isomers of a novel fl-branched unusual amino acid were designed and synthesized with high stereoselectivity （〉 90% de） and in 33%--44% overall yields by the use of 4（R/S）-5,5-dimethyl-4-phenyl-oxazolidin-2-one as the chiral auxiliary via asymmetric 1,4-Michael addition, direct or indirect azidation, hydrolysis and hydrogenation reactions.

关键词： asymmetric synthesis unusual amino acid oxazolidinone chiral auxiliary 2-amino-3-furan-2-yl- pentanoic acid

Conversion of N-Acyl-4-phenyl/benzyl-oxazolidine-2-thiones into Thiol Esters in the Presence of EtSH-K2CO3

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Chinese Journal of Chemistry 2005年第11期23卷 1561-1563页

作者： HU, Qi SUN, Ya-Ping WU, Yi-Kang State Key Laboratory of Bioorganic and Natural Products Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

N-Acyl-β-hydroxy-4-phenyl-oxazolidinethiones could be rapidly converted into their ethyl thiol esters in high yields by treatment with EtSH at 0 ℃ in CH3CN or 9 ： 1 （V ： V） THF-H2O in the presence of a catalytic... 详细信息

关键词： chiral auxiliary cleavage thiol ester aldol

An Efficient Enantioselective Synthesis of Blastmycinone

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Chinese Journal of Chemistry 2005年第11期23卷 1519-1522页

作者： YANG, Yong-Qing wu, Yi-Kang State Key Laboratory of Bio-organic and Natural Products Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

Blastmycinone, a degradation product of the antibiotic antimycin A, was synthesized with a TiCl4-mediated asymmetric aldolization as the key step. Some unexpected yet interesting chemistry was also observed.

关键词： lactone asymmetric synthesis aldol acylation chiral auxiliary