过渡金属催化的有机硼酸与不饱和键的加成反应

概述了过渡金属催化的有机硼酸与不饱和键的加成反应,包括铑催化、镍催化、钯催化三部分内容.     

Synthesis, reactions and structural features of monofluorinated cyclopropanecarboxylates

Monofluorinated cyclopropanecarboxylates are available in racemic or optically active form by transition metal-catalyzed reactions of vinylfluorides with diazoacetates. From α-fluorostyrene and tert-butyl diazoacetate in the presence of 2 mol% of an enantiopure bis(oxazoline) copper complex, a 81:19 mixture of tert-butyl trans- and cis-2-fluoro-2-phenylcyclopropanecarboxylates was obtained with high enantiomeric excess (ee) of 93 or 89%, respectively. The corresponding racemic ethylesters were used as starting materials for the synthesis of carboxamides, of the cis- and trans-isomers of analogues of tranylcypromine, an anti-depressive drug and several of its homologous fluorinated cyclopropylmethyl and cyclopropylethyl amines. Corresponding enantiopure cyclopropylmethanols and several of their derivatives were synthesized also. Solid state structures of a selection of these compounds were examined by X-ray crystallography. Particularly, the cis-configurated fluorinated phenylcyclopropane derivatives showed extremely close intermolecular CH?FC contacts. The shortest of such distances (2.17 Å) was found in the N-(4-bromophenyl)carbamate of (1S,2R)-(2-fluoro-2-phenylcyclopropyl)methanol.     

金属催化制备石墨烯的研究进展

石墨烯作为一种新兴的碳素材料,从一出现就引起了众多学者的关注.石墨烯具有许多新奇的特性,使得石墨烯在光电领域及微电子工业等有极大的应用潜力.但是目前难以实现大尺寸、高质量、宏量石墨烯的可控制备,限制了石墨烯的广泛应用.本文分析了各种石墨烯制备方法的利弊,重点从层数控制及大面积制备等方面对金属催化法进行了阐述,固态碳源金属催化法可以实现宏量制备大尺寸、高质量、薄且均匀的石墨烯.综述了金属催化制备石墨烯的相关机理研究,指出了目前研究的局限,并对石墨烯相变机理的下一步研究方向进行了展望.     

Regioselective Reduction of 1H-1,2,3-Triazole Diesters

Regioselective reactions can play pivotal roles in synthetic organic chemistry. The reduction of several 1-substituted 1,2,3-triazole 4,5-diesters by sodium borohydride has been found to be regioselective, with the C(5) ester groups being more reactive towards reduction than the C(4) ester groups. The amount of sodium borohydride and reaction time required for reduction varied greatly depending on the N(1)-substituent. The presence of a β-hydroxyl group on the N(1)-substituent was seen to have a rate enhancing effect on the reduction of the C(5) ester group. The regioselective reduction was attributed to the lower electron densities of the C(5) and the C(5) ester carbonyl carbon of the 1,2,3-triazole, which were further lowered in cases involving intramolecular hydrogen bonding.     

Application and Modification of Cyclometalated Ruthenium(II) Complex [Ru(o-C6H4-2-C5H4N)- (MeCN)4]PF6 for Atom Transfer Radical Polymerization

Polymerizations of n-butyl acrylate (BA), methyl methacrylate (MMA) and styrene (St) were promoted by the Ru(II) cyclometalated complex with labile MeCN ligand in the presence of Al(OiPr)₃. The polymerization proceeds via radical mechanism and requires the loss of MeCN ligand. The poor control over the polymerizations can be explained in terms of the traditional ATRP scheme. However, the controllability may be significantly improved by addition of reducing SnCl₂. Mechanism of the process is proposed.     

通过C(sp3)-H键活化构建C-P键合成氨基膦酸酯类化合物

氨基膦酸酯及其衍生物是一种重要的有机化合物,因其具有抗菌、抗真菌、酶抑制剂和催化抗体活性而广泛应于药物化学和农业化学。通过C(sp3)-H键活化构建C-P键的方法是合成氨基膦酸酯衍生物重要方法之一。本文以过渡金属体系和非金属体系进行分类,介绍了近年来通过C(sp3)-H键活化方法构建C-P键合成氨基膦酸酯类化合物的研究进展。     

Transition metal-catalyzed CH functionalization of arylacetic acids for the synthesis of benzothiadiazine 1,1-dioxides

Copper-catalyzed practical route for the synthesis of benzothiadiazine 1,1-dioxides has been developed. The method involves CH functionalization of arylacetic acids to form aromatic aldehydes and their subsequent condensation with 2-aminobenzenesulfonamide. This functional group tolerant approach furnished benzothiadiazine 1,1-dioxide derivatives in good to excellent yields. Broad substrate scope, inexpensive catalyst and high product yields are notable features of this protocol.     

Recent advances in synthesis of ketenimines

Ketenimines are a kind of reactive species that can be used as synthetic intermediates. In the last two decades, there has been a surge of interest in this class of building blocks and their applications, which has led to extensive research on ketenimine derivatives such as fluorine ketenimine, metal complexes of ketenimines, and the various methods of their preparation. Ketenimines have been prepared by a variety of methods, including photolysis, elimination, or rearrangement reactions. As well as, ketenimines can be prepared using a variety of useful reagents, including isocyanates, copper acetylide, amides, organometallic compounds, and metal complexes. An overview of these achievements is presented here.     

金属催化有机反应中的碱效应

众所周知, 在有机催化反应中经常用到不同的有机或无机碱, 许多碱本身也可以作为催化剂, 但化学家们对碱在化学转化中的作用并没有系统和明确的认识, 许多反应中碱的选择都是经过大量的条件实验确定的. 针对这些问题, 席振峰课题组对文献中碱的作用进行了系统归纳和总结, 分析了碱的多种因素对反应的影响并提出了一些规律性的结论, 对理解碱效应具有很高的参考价值.     

金属催化端炔与亚胺衍生物亲核加成制备炔丙基胺的研究进展

综述了端炔与C=N双键亲核加成制备炔丙基胺的合成方法的研究进展.其中包括醛亚胺的间接或直接偶联反应,烯胺的间接偶联反应,酮亚胺的间接或直接偶联反应等.参考文献30篇.