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1.
朱仁义  廖奎  余金生  周剑 《化学学报》2020,78(3):193-216
P-手性膦氧类化合物在药物化学、有机合成化学、生命及材料科学等领域具有重要的应用价值和潜能,是一类受到广泛关注的优势结构.近年来,针对这一结构的不对称催化构建取得了显著进展.本综述旨在从三级膦氧化物的去对称化反应和(动态)动力学拆分反应以及二级膦氧化物参与的不对称反应三种策略出发,介绍目前用于构建P-手性膦氧化物的不对称催化合成方法及最新研究进展.藉此也对这些反应的机理及其优势与不足之处进行简要讨论,为从事有机合成和有机膦化学相关的研究人员提供一些有益参考和借鉴.  相似文献   

2.
A facile, one-pot vinylation of secondary phosphine chalcogenides with alkyl(or aryl) vinyl sulfoxides has been elaborated. The vinylation comprises the nucleophilic addition of secondary phosphine chalcogenides to the vinyl sulfoxides (~50 mol% KOH, dioxane, 25–40°C, 1 h) followed by the elimination of sulfenic acids from the adducts (additional equivalent of KOH, 60–70°C, 1.5–2.0 h), the yields of target tertiary vinyl phosphine chalcogenides reaching 92%.  相似文献   

3.
Abstract

Phosphine, generated from elemental phosphorus in the system KOH-toluene-H2O, reacts with vinyl sulfides under free radical conditions (AIBN, dioxane, 65–70°C, atmospheric pressure) to form regiospecifically tris[2-(organylthio)ethyl]phosphines, which are readily oxidized in air to corresponding tris[2-(organylthio)ethyl]phosphine oxides.  相似文献   

4.
Nucleophilic addition of secondary phosphine oxides to aromatic aldehydes proceeds under mild conditions (20-60°C, 10-40 h) and provides [bis(2-organylethyl)](arylhydroxymethyl)phosphine oxides in high yields.  相似文献   

5.
6.
刘勇军  钟鸣  宋琤  盛寿日  侯豪情  宋才生 《应用化学》2018,35(11):1289-1294
以苯酚、对二溴苯及苯基磷酰二氯为原料合成出二(4-苯氧基苯基)苯基氧磷(BPOPPO)。 三氯化铝(AlCl3)为催化剂,通过缩聚反应,BPOPPO与对苯二甲酰氯(TPC)反应制备出一种含有三苯基氧磷结构的聚醚醚酮酮(P-PEEKK)树脂。 采用傅里叶变换红外光谱仪(FT-IR)、差示扫描量热仪(DSC)、热重分析仪(TGA)和广角X射线衍射(WAXD)等技术手段对P-PEEKK树脂的结构和性能进行表征。 结果表明,P-PEEKK树脂属于非晶聚合物,玻璃化转变温度(Tg)较高,为190.5 ℃;热分解温度(T5%)为515 ℃,耐热性能较好;极限氧指数(LOI)为42,阻燃性能好,为难燃材料;易溶解于氯仿、1,2-二氯乙烷、N,N-二甲基乙酰胺等有机溶剂中,溶解性能较好,便于涂膜加工;拉伸强度为62 MPa,力学性能较好。  相似文献   

7.
研究实现了多功能手性膦催化的3-芳酰基丙烯酸酯和烯酮的不对称分子间Rauhut-Currier反应,为多羰基手性化合物的构建提供了一种新方法.在使用(S,RS)-X8作为催化剂和甲苯作为溶剂的条件下,一系列含有不同取代基团的3-芳酰基丙烯酸酯和烯酮均可顺利地发生不对称Rauhut-Currier反应,从而高产率且高对映选择性地生成相应的产物.对照实验表明多功能手性膦催化剂中的N-H键对反应的对映选择性的控制起到了至关重要的作用;膦谱监测实验结果表明手性膦催化剂对烯酮的Michael加成是该反应的启动步骤.  相似文献   

8.
采用二阶微扰理论的MP2/6-31G(d,p)方法对气相中烯丙基负离子与N2O的反应机理进行了理论计算研究, 并在相同基组下进一步用CCSD(T)方法进行了单点能的校正. 计算结果表明, 该反应存在三条反应通道, 产物分别为cis-CH2CHCNN-+H2O, trans-CH2CHCNN-+H2O和CH2CCH-+N2+H2O, 其中生成cis-CH2CHCNN-和trans-CH2CHCNN-的两条通道为相互竞争的主反应通道, 计算结果与实验相吻合. 同时利用传统的过渡态理论, 计算了各反应通道在298 K时, 速控步骤的反应速率常数k(T).  相似文献   

9.
本文应用加压原位(in-situ)核磁共振技术,在反应温度70~75℃,压力1.0~2.0MPa,氘代苯为溶剂,偶氮二异丁腈(AIBN)为引发剂的条件下探索了磷化氢与丙烯腈,4-乙烯基吡啶,烯丙基胺,丙烯酰胺,氨基吡啉和N-乙烯基咔唑的自由基加成反应,结果表明除氨基吡啉之外的其它五种含氮化合物均能与磷化氢发生反应,从而找到合成含氮有机膦的良好路线。  相似文献   

10.
The structures, energies, and natural atomic charges of 2-dimethylaminophenol oxide, 2-Me2N-(O)C6H4OH, and 2-dimethylphosphinylphenol, 2-Me2P(O)C6H4OH, in three different conformations were computed at the ab initio MP2/6-31G* level. Computed natural charges indicate distributions of electron density in amine oxides and phosphine oxides that are quite different from what is normally assumed on the basis of the formal charges in the usual representations of these compounds. The charges on nitrogen and phosphorus in these compounds are typically computed to be approximately zero on nitrogen and +2 on phosphorus, and the oxygen is considerably more negative in the phosphine oxide than in the amino oxide. Electronegativity differences thus play a larger role and formal charges a smaller one in determining atomic charges in these compounds than is generally believed. Despite the more negative oxygen in phosphine oxides, amine oxides are computed to be considerably more basic when participating in hydrogen bonding. Calculations treating the computed natural charges on these six conformations as point charges for classical approximations of the coulombic energies support the idea that the quantum mechanically computed relative energies are largely determined by coulombic interactions.  相似文献   

11.
Aerobic Oxidation of Methyl Vinyl Ketone in Supercritical Carbon Dioxide   总被引:1,自引:0,他引:1  
Theaerobicoxidationofethylenetoacetaldehydeandterminalolefinstocorrespondingalkan 2 onescat alyzedbypalladium(II)andcopper(IIorI)saltsarecol lectivelyknownasWackeroxidations (Scheme 1) .1Theyareveryimportantinbothsyntheticandindustrialchem istry .Treatmentoft…  相似文献   

12.
Solid‐state NMR spectroscopy of selected phosphine oxides adsorbed on silica surfaces establishes the surface mobilities, even of phosphine oxides with high melting points. Crystal structures of the adducts Ph3PO ? HOSiPh3 and Cy3PO ? H2O indicate that the interactions with silica involve hydrogen bonding of the P?O group to adsorbed water and surface silanol groups.  相似文献   

13.
聚甲基乙烯酮(PMVK)、聚叔丁乙烯酮(PTBVK)、聚衣康酸酯(PI)、1,2-聚丁二烯(1,2-PBD)带有结构、成分各异的大侧基,是可以比较侧基对分子链无扰尺寸和极性影响的典型乙烯基聚合物.基于构象构型统计方法,通过建立不同的结构模型下统一的计算公式,计算得到无规PMVK、PI、PTBVK和1,2-PBD链均方回转半径特征比稳定值依次为3.09、2.96、1.72和1.11,无规PI、PMVK和PTBVK电偶极矩特征比分别为1.57、0.79和0.45.从特性黏数、特征比及温度系数,特征比的能量微分值比较,PMVK的各物理量随构型和链长的规律具有更丰富的变化,PI和PTBVK均方回转半径与均方电偶极矩规律相关曲线差异相对较大,如PTBVK能量微分值差异可达到20.12×10~(-2)mol/J.PI和1,2-PBD侧基的结构虽然不同,但由于物理机理的一致性,其特征量均比较稳定.因此,针对聚合物侧基差异建立计算模型的比较研究是十分必要的.  相似文献   

14.
Extensive DFT calculations provide detailed mechanistic insights into the metal-free reduction of phosphine oxide Ph3P=O by using chlorination reagents O=CClX (X=COCl, Cl, OCCl3 and Ph) and H2. Fast electrophilic attack to the P=O group oxygen atom is favored by exergonic CO2 release to form phosphonium Ph3PCl+ and chloride Cl, which may slowly cleave H2 by an unstable HPh3PCl complex yielding Ph3PH+ and Cl ions in solution. Moderate heating is required to accelerate the slow H2-activation step and to eliminate HCl to form phosphine Ph3P instead of Ph3PH+Cl salt as the desired product. Though partially quenched by Ph3P (and reactant Ph3P=O if present), borane B(2,6-F2C6H3)3 can be still combined with Cl and Ph3P as reactive frustrated Lewis pair (FLP) catalysts.  相似文献   

15.
Thereisconsiderablecurrentinterestinorgamcreactionsunderndcrowaveirradiationl.SomereactionsthatneededalongtAnetocomplete(i.e.severalhoursorseveraldays)couldbecatriedoutinseveralminutesunderndcrowavepromotion'-',andasthecasemaybe,somellewreactionswerefound'.Generally,ketalsareusuallyobtainedwhenethylortho-formatereactswithvariousketonesunderacidiccondihons"',butinthesamesituaioftanabnormalreachonalsotookplaceundermicrowaveirmdiahon(75owx7o$5oHz),andaseriesofnewcompounds(5,6,7,8)wereobtainedfr…  相似文献   

16.
White phosphorus reacts with allyl bromide in the system KOH-dioxane-H 2 O at room temperature to form tris(propen-2-yl), bis(propen-2-yl)(E-propen-1-yl), and bis(E-propen-1-yl)(propen-2-yl)phosphine oxides in a total quantitative yield, their molar ratio being 1:0.5:0.1.  相似文献   

17.
丙酮一步法合成甲基异丁基酮催化剂研究   总被引:3,自引:0,他引:3  
用浸渍法制备了丙酮一步法合成甲基异丁基酮负载型催化剂,考察了载体的预处理温度、添加镧助剂对催化剂性能的影响;用BET法测定了催化剂的表面积;采用H2-O2滴定法测定Pd的分散度.结果发现,用经过1.023K焙烧过的Al2O3为载体的催化剂具有较好的催化性能,添加镧助剂后催化剂的分散度、活性有较大的提高.  相似文献   

18.
Abstract

The reaction of (CF3)2P-P(CF3)2 with [Ru3(CO)12] yielded compounds : [Ru14(CO)13{μ-P(CF3)2)2] (1), [Ru4(CO)14{μ-P(CF3)2}2] (2), and [Ru4(CO)11{μ-P(CF3)2}4] (3); reaction with [μ-H)4Ru4(CO)12] yielded (1) and [(μ-H)3Ru4(CO)12{μ-P(CF3)2}] (4). The reaction of (CF3)2PH with [Ru3(CO)12] yielded compounds (1) and (4) and compounds (1) and (2) using cluster : ligand ratios of 1:1 and 1:2 respectively. All the compounds have been characterised by X-ray crystallography; a schematic diagram of their structures is shown in Figure 1. The fluxional behaviour of the hydrides in (4) was studied using variable temperature 1H NMR spectroscopy (see Figure 2). The result of this study was used in the assignment of hydride positions of (4) in the solid state.  相似文献   

19.
We report the cycloaddition between vinyl aziridines and arynes. Depending on the reaction conditions and the choice of the aryne precursor, the aziridinium intermediate can be trapped through two distinct mechanistic pathways. The first one proceeds through a formal [5+2] cycloaddition to furnish valuable multi-substituted benzazepines. In the second pathway, the aziridinium is intercepted by a fluoride ion to afford allylic fluorides in good yields. Both reactions proceed stereospecifically and furnish enantiopure benzazepines and allylic fluorides.  相似文献   

20.
在研究5-甲氧基-3,4-二卤-2(5H)-呋喃酮的Heck反应过程中,意外发现了5-甲氧基-3,4-二卤-2(5H)-呋喃酮与配体三丁基膦的反应,得到两个新季鏻盐化合物,产物结构被IR、1H-NMR、ESI-MS测试结果所证实。  相似文献   

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