Cumulated Trienephosphine Oxides. Bimolecular Trapping of an Alkylidenecyclopropylidene
摘要:
Dihalocarbene addition to allenic phosphine oxides occurs mainly at the allylic double bond. Treatment of dibromocarbene adducts with BuLi leads to cumulated trienephosphine oxides. In some cases, the intermediate alkylidenecyclopropylidene (or its precursor) is exceptionally stabilized, and this carbene (or carbenoid) is trapped by the corresponding cumulated trienephosphine oxide in a bimolecular process. The resultant spiropentane is formed in a regio- and stereoselective manner.
Palladium-Catalyzed Cascade C−O Cleavage and C−H Alkenylation of Phosphinyl Allenes: An Expeditious Approach to 3-Alkenyl Benzo[<i>b</i>
]phosphole Oxides
作者:Teng Liu、Xue Sun、Lei Wu
DOI:10.1002/adsc.201800103
日期:2018.5.16
time. The palladium‐catalyzed intramolecular cyclization provides an unprecedented cascade C−O cleavage and direct C−H alkenylation toward novel 3‐alkenyl benzo[b]phosphole oxides, along with broad group tolerance and high regioselectivity. Control experiments and mechanisticstudies explain the sequential performance of C(sp3)‐OAr cleavage and P=O directed C(sp2)‐Hactivation.
首次建立了由氧化膦定向的次膦基烯丙二烯分子内环化反应。钯催化的分子内环化作用提供了前所未有的级联C-O裂解和将CH-H烯基化成新型3-烯基苯并[ b ]磷氧化物的方法,并具有宽基团耐受性和高区域选择性。对照实验和机理研究解释了C(sp 3)-OAr裂解和P = O定向C(sp 2)-H活化的顺序性能。
Rhodium-Catalyzed Enantioselective Radical Addition of CX<sub>4</sub>
Reagents to Olefins
作者:Bo Chen、Cheng Fang、Peng Liu、Joseph M. Ready
DOI:10.1002/anie.201704074
日期:2017.7.17
We describe the synthetically useful enantioselective addition of Br−CX3 (X=Cl or Br) to terminal olefins to introduce a trihalomethyl group and generate optically active secondary bromides. Computational and experimental evidence supports an asymmetric atom‐transfer radical addition (ATRA) mechanism in which the stereodetermining step involves outer‐sphere bromine abstraction from a [(bisphosphine)RhIIBrCl]
我们描述了Br-CX 3(X = Cl或Br)的合成有用的对映选择性加成到末端烯烃中以引入三卤甲基并生成光学活性的仲溴化物。计算和实验证据支持不对称原子转移自由基加成(ATRA)机理,其中立体确定步骤涉及通过苄基自由基中间体从[(bisphosphine)Rh II BrCl]络合物中提取外层溴。这种机理在不对称催化中显得空前。
Intermolecular Cyclization between Carboranylphosphines and Electron-Deficient Alkynes
and facile method to synthesize zwitterionic nido-carborane-fused five-membered P-heterocycles was developed. Intermolecular cyclization between carboranylphosphines and electron-deficient alkynes occurred at 50 °C in THF, affording the products with up to 82% yield. For unsymmetrical alkynes, the more electrical-deficient site is selectively connected to phosphorus in the products. Structures of three
Synthesis and characterization of new PNNP-type chiral ligands
作者:Burcu Tezcan、Bilgehan Güzel
DOI:10.1080/10426507.2018.1539997
日期:2019.5.27
Abstract Polydentate ligands having both soft and hard centers are very effective ligands for the preparation of transition metal complexes. PNNP-type tetradentate diaminodiphosphine ligands are most preferred ligand types cause of their good efficiency for the asymmetric reactions. In this study, three different iminophosphine derivative PNNP-type chiral ligands were synthesized using (R)-(+)-1,1′-Binaphthyl-2
[EN] PHOSPHINYL AMIDINE COMPOUNDS, METAL COMPLEXES, CATALYST SYSTEMS, AND THEIR USE TO OLIGOMERIZE OR POLYMERIZE OLEFINS<br/>[FR] COMPOSÉS DE PHOSPHINYLAMIDINE, COMPLEXES DE MÉTAL, SYSTÈMES DE CATALYSEUR, ET LEUR UTILISATION POUR OLIGOMÉRISER OU POLYMÉRISER DES OLÉFINES
申请人:CHEVRON PHILLIPS CHEMICAL CO
公开号:WO2011082192A1
公开(公告)日:2011-07-07
N2-phosphinyl amidine compounds, N2-phosphinyl amidinates, N2-phosphinyl amidine metal salt complexes, N2-phosphinyl amidinate metal salt complexes are described. Methods for making N2-phosphinyl amidine compounds, N2-phosphinyl amidinates, N2-phosphinyl amidine metal salt complexes, and N2-phosphinyl amidinate metal salt complexes are also disclosed. Catalyst systems utilizing the N2-phosphinyl amidine metal salt complexes and N2-phosphinyl amidinate metal salt complexes are also disclosed along with the use of the N2-phosphinyl amidine compounds, N2-phosphinyl amidinates, N2-phosphinyl amidine metal salt complexes, and N2-phosphinyl amidinate metal salt complexes for the oligomerization and/or polymerization of olefins.