The crystal and molecular structure of carboxylmethyltriphenylarsonium salt, Ph3 As+CH2 COO^1 11/2H2O

膦、胂叶立德能与醛、酮等通过Wittig反应合成烯烃衍生物,在有机合成中具有很大的应用价值。其反应活性与结构的关系已有深入的讨论,有关分子结构的研究工作仍在继续中。我们按文献[4]合成甲氧羰基亚甲基三苯基胂,熔点153～154℃,然后在甲醇:乙醇为1:2混合溶剂中培养单晶并进行X光晶体     

Application of organic selenides and tellurides in organic synthesis

This paper describes the progress on the synthesis of organic selenides and tellurides and their application in organic synthesis.Low valent selenium and telluronium compounds having high reducing selectivity can be used to form carbon-hydrogen bonds as special reducing reagents.Telluronium ylides can react with aldehydes and ketones by Wittig-type condensation to produce (E)-configuration alkenes stereoselectively.α-Phenylselanyl arsonium ylides were prepared by transyl-idation reaction of arsonium ylides with phenylselanyl halides which can undergo Wittig-type reactions with carbonyl compounds to give (Z)-α-selanyl-α,β-unsaturated compounds with high stereoselectiv-ity.Zirconium,tin,boron,halogen,metal or hetero-atom were introduced in organoselenium and telluronium compounds as new difunctional group reagents.Under transition metal catalysis,the corresponding cross coupling reactions provide new methods of formation of carbon-carbon double bonds,which were used in the stereoselective synthesis of     

亚烃基丙二酸亚异丙酯的共轭加成-α -烃化串联反应

亚烃基丙二酸亚异丙酯与格氏试剂的共轭加成和α-烃化串联反应提供了一种合成不对称双取代丙二酸亚异丙酯的新方法。由于不对称双取代丙二酸亚异丙酯易水解失羧和醇解失羧转化成相应的羧酸及酯,因此本法也是合成α-及β-高取代的羧酸及其酯的有效方法。     

钯催化下活性亚甲基化合物的烯丙基化相转移反应

钯催化下活性亚甲基化合物的烯丙基化反应在有机合成中是一种十分有用的方法。例如在双三苯基膦二氯化钯催化下丙二酸二乙酯、α-砜基乙酸乙酯等活性亚甲基化     

A Facile One-pot Synthesis of 2,5-Disubstituted Oxazoles Using Poly[styrene（iodosodiacetate）]

2,5-Disubstituted oxazoles were prepared conveniently by treatment of aromatic α-methyl ketones and nitriles with poly[styrene(iodosodiacetate)] in a one-pot manner.     

Solid Phase Synthesis of Ethyl β-Substituted Indolepropionates

A facile solid phase synthesis of ethyl β-substituted indolepropionates is reported. Condensation between indole, polymer-supported cyclic malonic acid ester and aldehyde yielded the trimolecular adducts, which was cleaved by pyridine/EtOH to release the final products in good yield with high purity.     

α,β—不饱和砜在有机合成中的应用

随着有机硫化合物在合成中的广泛应用,α,β-不饱和砜显示了多样的反应性能,已成为有机合成中极为重要的中间体。它具有下列结构特点: 1.由于分子中砜基的拉电子效应,使得共轭不饱和双键具有较强的缺电性,因此α,β-     

聚苯乙烯二醋酸碘苯的合成及其在缩氨脲去保护基形成羰基化合物反应中的应用

缩氨脲不仅可用于羰基化合物的分离和纯化[1] ,而且在有机合成中也常用于保护羰基[2～ 5] .因此 ,研究缩氨脲去保护基再生成相应的羰基化合物的方法仍然是有机合成方法中重要的研究课题 .文献报道使缩氨脲去保护基的常用试剂有邻苯二酐[1] 、浓盐酸[6] 、阳离子交换树脂[6,7] 、氯化亚钛[8] 、溴酸钾[9] 和氯化铜 ( )二水合物[10 ] 等 .　　最新研究[11] 发现 ,二醋酸碘苯在含水的乙腈溶液中是酮缩氨脲去保护基形成酮的有效试剂 ,具有反应条件温和 ,产率较高的特点 .但是 ,利用二醋酸碘苯进行反应时 ,同时生成副产物碘苯 ,它难于从产物中分…     

α-芳硒基羰基化合物的合成

茂钛硒化物分别与α－溴代酮和α－溴代酯反应生产了相应的α－硒酮和α－硒代酯，茂钛硒配合物由Ｃｐ２ＴｉＣｌ２／２ｉ－ＢｕＭｇＢｒ／ＴＨＦ体系还原二芳基二硒醚得到。