镝促进下醛、酮与炔丙基溴及苯基炔丙基溴的高 选择性反应

在金属镝的促进下,醛、酮可与炔丙基溴反应,高选择性高产率地得到相应的高炔丙醇,没有发现连二烯醇的存在。当用苯基炔丙基溴代替炔丙基溴与醛、酮反应时,主要得到了相应的连二烯醇,而没有发现高炔丙醇的存在,由此提出了六元环过渡态的反应机理。     

炔丙基自由基在有机合成化学中的应用

炔烃的合成与转化一直是有机合成化学的一个重要研究内容. 其中, 炔丙位官能化是实现炔烃合成与转化的一个重要途径. 相对于经历阳离子中间体途径的炔丙位官能化反应, 自由基途径的炔丙位官能化反应在最近十年才得以发展, 且与前者也已形成互补之势. 该类炔丙基自由基既能够通过炔丙位的碳杂键断裂生成, 又可通过自由基对1,3-烯炔的加成生成. 同时, 由于炔丙基自由基存在自由基与炔烃的共轭结构, 使得该自由基既能够直接对金属物种加成参与炔丙位的官能化反应, 又能够异构成联烯自由基后对金属物种加成, 继而参与联烯化合物的合成. 此外, 炔丙基自由基还可以被进一步氧化成炔丙基阳离子后参与后续的有机转化. 本综述根据炔丙基自由基所参与的反应类型, 对近年来炔丙位自由基参与的有机反应进行了简要总结.     

金属单质锡促进的水相中醛的Barbier类型炔丙基化反应

报道了一种简单、 高效且快速的醛的炔丙基化反应体系. 使用廉价的金属单质锡粉, 在路易斯酸SnCl₂·2H₂O促进下, 实现了水相中醛羰基化合物的Barbier类型炔丙基化反应, 高收率、高区域选择性地得到单一的高炔丙基醇产物(收率99%). 该方法具有底物适用范围广、反应条件温和(30℃)、环境友好(以水为介质)及反应速度快(30 min内反应原料基本消失)等优点. 另外, 在使用肉桂醛为底物且将反应温度升至55℃时, 意外地得到了中等收率的新型高度对称的烯炔醚化合物.     

端炔丙基化合物的聚合反应研究进展

端炔丙基化合物的聚合产物以其优异电导性,非线性光学特性等性能而引起人们的广泛兴趣,本文了近年来端炔丙基化合物的氧化聚合、易位聚合、自由基聚合、缩聚等聚合的研究进展。     

高烯丙基醇和高炔丙基醇的无溶剂合成

在活化锌粉的促进下,通过羰基化合物的烯丙基化和炔丙基化反应,实现了高烯丙基醇和高炔丙基醇的快速无溶剂合成,收率72％～88％。产物的结构经1^H NMR,MS和元素分析确证。     

铜催化β-酮酸炔丙醇酯的不对称脱羧炔丙基烷基化反应

正Angew.Chem.Int.Ed.2014,53,1410~1414通过过渡金属催化的炔丙基取代反应,可以非常便利地在反应产物上引入富电子的碳碳叁键官能团,进而可以实现多种复杂化合物的合成.因此这一反应近来受到越来越多的关注并取得了很大的进展.多种过渡金属如Ru、Cu、Ni等及氮、氧、碳等亲核试剂已被成功应用于该反应中.但利用简单的酮及其烯醇衍生物作为亲核试剂的炔丙基取代化反应目前仍鲜有成功的报导.中国科学院大连化学物理研究所胡向平研究员和徐杰研究员等利用手性铜催     

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.     

镍催化的芳基硼酸偕二氟炔丙基化反应

偕二氟炔丙基取代的芳烃是一类非常重要的化合物, 但传统合成该类化合物的方法却存在很大局限性. 以过渡金属催化直接向芳烃偕二氟炔丙基化是一种高效简洁制备上述化合物的方法. 以廉价易得的Ni(NO₃)₂·6H₂O为催化剂, 首次实现了镍催化下芳基硼酸与α,α-二氟炔丙基溴的偶联反应. 该反应不仅温和高效、原料廉价易得、官能团兼容性良好, 而且还能进行克量级放大和对生物活性分子的后期氟修饰, 从而为新药研发提供了一种有效手段.     

锡存在下取代的炔丙基溴与醛反应的选择性

报道三甲基硅基和苯基取代的炔丙基溴在锡存在下与醛的反应, 并讨论了反应的选择性。三甲基硅基炔丙基溴与醛的反应产率约为71-84%。产物中丙二烯醇与高炔丙基醇之比在44 :56到25 : 75之间, 苯基炔丙基溴的反应得到了产物丙二烯醇。     

侧基对N-炔丙基酰胺螺旋共聚物光学活性的影响

设计并合成了5个系列的带有不同侧基的手性-非手性N-炔丙基酰胺共聚物,以铑有机配合物为催化剂对单体实施聚合反应得到高产率(>95%)的共聚物,聚合物具有高立构规整性(cis-含量高于94%).利用圆二色(CD)及紫外-可见吸收(UV-Vis)光谱技术对共聚物的二级结构及光学活性进行了表征,当非手性单体的酰胺侧基体积适中时,共聚物具有较高的光学活性,部分共聚物的光学活性甚至高于纯手性聚合物.表明通过选择合适的手性-非手性共聚单体及单体配比,可获得具有高光学活性的螺旋聚合物.     

Stereoselective synthesis of tetracyclic indolines via gold-catalyzed cascade cyclization reactions

A reliable synthetic route to fused polycyclic indolines is documented by the development of a stereoselective gold catalyzed cascade cyclization of indole propargylic alcohols.     

Solid-phase synthesis of indolines via palladium-catalyzed cyclization

The solid-phase synthesis of indolines from resin-bound 2-bromophenylacetylated amino acids is described. The exhaustive reduction of solid-support bound amides with borane afforded the requisite secondary amines that, following the palladium-catalyzed intramolecular cyclization and cleavage, provided the corresponding disubstituted indolines.     

Efficient construction of fused indolines with a 2-quaternary center via an intramolecular Heck reaction with a low catalyst loading

An efficient construction of fused indolines with a 2-quaternary center through a palladium-catalyzed intramolecular Heck reaction of N-(2(2-halobenzoxyl)-2,3-disubstituted indoles is disclosed. This protocol provided a straightforward access to diverse fused indolines with good functional group tolerance.     

Copper-catalyzed enantioselective propargylic amination of nonaromatic propargylic esters with amines

The enantioselective propargylic amination of propargylic pentafluorobenzoates bearing an alkyl group at the propargylic position with amines in the presence of catalytic amounts of a copper complex and an optically active diphosphine such as BINAP has been found to give the corresponding propargylic amines in good yields with high enantioselectivity.     

Nucleophilic addition of grignard reagents to 3-acylindoles: stereoselective synthesis of highly substituted indoline scaffolds

3-Acylindoles undergo nucleophilic-type reactions with Grignard reagents to efficiently afford either cis- or trans-substituted indolines, depending on the different quenching procedures. The enolate intermediate could be trapped by aryl acyl chlorides to provide indolines bearing a quaternary carbon center with high stereoselectivity. In contrast, the use of benzyl bromide as an electrophile results in the fragmentation of the indole ring. The indoline products could be easily transformed into indoles through oxidation with DDQ in a one-pot manner.     

Synthesis of 6-methoxyindoles and indolines. Regioselective c-6 bromination of indolines and subsequent nucleophilic substitution with a methoxyl group

Regioselective bromination of the 6-position of indolines was investigated. Treatment of indolines with bromine in sulfuric acid in the presence of silver sulfate or with bromine in superacid afforded the 6-bromoindolines, which were converted to 6-methoxyindolines and indoles.     

Asymmetric synthesis of trans-2,3-disubstituted indoline derivatives

A novel method for asymmetric synthesis of trans-2,3-disubstituted indolines has been developed. The strategy involves the (-)-sparteine-mediated electrophilic substitution of 2-benzyl N-pivaloylaniline with aromatic or α,β-unsaturated aldehydes and subsequent intramolecular nucleophilic substitution. The simple protocol for two-step process can produce highly enantioenriched indolines 3a-o up to 98:2 er.     

Palladium-catalyzed direct coupling reaction of propargylic alcohols with arylboronic acids

The direct coupling of propargylic alcohols with arylboronic acids has been achieved using palladium catalyst. Various propargylic alcohols and arylboronic acids can be coupled to afford the corresponding allenic and propargylic arenes, which are selectively produced depending on the substituent on the propargylic alcohol, respectively.     

Ruthenium-catalyzed propargylic substitution reaction of propargylic alcohols with thiols: a general synthetic route to propargylic sulfides

A novel cationic methanethiolate-bridged diruthenium complex [Cp*RuCl(mu2-SMe)2RuCp*(OH2)]OTf (1e) has been disclosed to promote the catalytic propargylic substitution reaction of propargylic alcohols bearing not only terminal alkyne group but also internal alkyne group with thiols. It is noteworthy that neutral thiolate-bridged diruthenium complexes (1a-1c), which were known to promote the propargylic substitution reactions of propargylic alcohols bearing a terminal alkyne group with various heteroatom- and carbon-centered nucleophiles, did not work at all. The catalytic reaction described here provides a general and environmentally friendly preparative method for propargylic sulfides, which are quite useful intermediates in organic synthesis, directly from the corresponding propargylic alcohols and thiols.     

Chiral Phosphoric Acid Catalyzed Kinetic Resolution of Indolines Based on a Self‐Redox Reaction

A strategy for oxidative kinetic resolution of racemic indolines was developed, employing salicylaldehyde derivative as the pre‐resolving reagent and chiral phosphoric acid as the catalyst. The iminium intermediate, formed by the condensation reaction of an enantiomer of indoline with salicylaldehyde derivative, was hydrogenated by the same enantiomer of indoline to afford another enantiomer of indoline by a self‐redox mechanism. The oxidative kinetic resolution of 2‐aryl‐substituted indolines proceeded to give enantiomers in good yields with excellent enantioselectivities.