Unified Approach to Imidodiphosphate-Type Brønsted Acids with Tunable Confinement and Acidity
作者:Sebastian A. Schwengers、Chandra Kanta De、Oleg Grossmann、Joyce A. A. Grimm、Natascha R. Sadlowski、Gabriela G. Gerosa、Benjamin List
DOI:10.1021/jacs.1c07067
日期:2021.9.15
confinement, one of which catalyzes the first highly enantioselective (>95:5 er) sulfoxidation of methyl n-propyl sulfide. Furthermore, the methodology delivers a novel, rationally designed super acidic catalyst motif, imidodiphosphorbis(iminosulfonylimino)imidate (IDPii), the extreme reactivity of which exceeds commonly employed super-Brønsted acids, such as trifluoromethanesulfonicacid. The unique reactivity
我们设计并实现了一种高效且操作简单的单烧瓶合成基于亚胺二磷酸盐的布朗斯台德酸。该方法通过六氯双磷鎓盐的连续氯化物取代进行,提供对亚胺二磷酸盐 (IDP)、亚氨基亚胺二磷酸盐 ( i IDP) 和亚胺二磷亚胺酸盐 (IDPi) 的快速访问。这些特殊的酸催化剂具有广泛的酸度范围(在 MeCN 中p K a从~11 到 <2)和易于调节的受限活性位点。我们的方法能够获得以前难以捉摸的具有特别高结构限制的催化剂支架,其中一个催化甲基n的第一个高度对映选择性 (>95:5 er) 磺化-丙基硫醚。此外,该方法提供了一种新颖、合理设计的超酸性催化剂基序,即亚氨基二磷(亚氨基磺酰基亚氨基)亚胺酸酯(IDPii),其极端反应性超过了常用的超布朗斯台德酸,如三氟甲磺酸。一种此类 IDPii 催化剂的独特反应性已在甲硅烷基乙烯酮缩醛与作为亲电烷基化试剂的甲醇的第一次 α-甲基化反应中得到证明。
Tetrafluoroaryl Phosphonic Acid Functionalized Polyphosphazenes – Synthesis, Characterization, and Evaluation of Proton Conductivity
phosphazene derivatives was effected by the reaction with trimethylsilyl bromide. The resulting silyl phosphonates were converted into the corresponding phosphonic acids by exposure to an excess of methanol. Proton conductivities of the novel phosphonic acid derivatives of poly‐ and cyclotriphosphazenes were studied by electrochemical impedance spectroscopy under anhydrous conditions.
描述了一种将四氟芳基膦酸酯部分结合到环状三磷腈和线性磷腈树脂中的收敛方法。我们的高收率程序是基于用p -HO(C 6 F 4)P(O)(OR)2处理氯化聚和环三磷腈的方法(R = Me,Et)在碳酸钾存在下。改性的环三磷腈的表征通过NMR和IR光谱以及通过质谱法完成。类似地,用膦酸酯修饰的磷腈树脂通过NMR和IR光谱以及GPC表征。通过与三甲基甲硅烷基溴的反应来实现新型磷腈衍生物中三甲基甲硅烷基的乙基的交换。通过暴露于过量的甲醇将所得的甲硅烷基膦酸酯转化为相应的膦酸。通过在无水条件下的电化学阻抗谱研究了聚和环三磷腈的新型膦酸衍生物的质子电导率。
Solvent effect on simple and high yield synthesis of polydichlorophosphazene precursor Cl<sub>3</sub>PNSiMe<sub>3</sub>
作者:Elif Büşra Çelebi、Ferda Hacıvelioğlu
DOI:10.1039/d1nj03721h
日期:——
polymerisation mechanism of this material enables unique features such as the preparation of well-defined block and star polymers or organic–inorganic hybrid copolymers. Therefore, a reproducible highyieldsynthesis of Cl3PNSiMe3 from readily available and cheap chemicals under mild conditions is an important issue to be solved. In this study, PCl5 was reacted with hexamethyldisilazane at 0 °C in various
Cl 3 P NSiMe 3在室温下的缩聚是生产聚二氯磷腈的最佳方法之一。这种材料聚合机制的活性阳离子性质能够实现独特的功能,例如制备明确定义的嵌段和星形聚合物或有机-无机杂化共聚物。因此,在温和条件下从易得且廉价的化学品中可重现的高产率合成 Cl 3 P NSiMe 3是一个需要解决的重要问题。在本研究中,PCl 5在 0 °C 下在各种溶剂中与六甲基二硅氮烷反应,以研究 Cl 3 P NSiMe 3的形成效率. 1 H 和31 P NMR 光谱技术用于监测反应进程并检测反应混合物中可用的中间体。非极性溶剂如正戊烷大大减少了副产物如 Cl 3 P NH 和环状磷腈衍生物的形成。因此,Cl 3 P NSiMe 3的分离产率提高到75%。Cl 3 P NSiMe 3的纯度超过 97%,经1 H、31 P、13 C 和29Si NMR光谱技术。此外,在甲苯中进行的反应导致在没有分离任何磷腈中间体的情况下,由
Syntheses and structures of an unsolvated tetrakisimidophosphate {Li3[P(NBut)3(NSiMe3)]}2 and the face-sharing double-cubane {Li2(THF)[P(O)(NBut)2(NHBut)]}2
The treatment of Me3SiNP(NHBut)3 with three equivalents of LiBun in toluene produces Li3[P(NBut)3(NSiMe3)]}2 comprised of a Li6N6 cyclic ladder capped on the two hexagonal faces by μ3-PNSiMe3 groups; the corresponding reaction of OP(NHBut)3 yields the face-sharing double-cubane Li2(THF)P(O)(NBut)2(NHBut)}2 with a central Li2O2 ring.
The synthesis and characterisation of novel polyphosphazene nanocarriers, based on hydrophilic polyalkylene oxide Jeffamine M1000 and hydrophobic steroids with a glycinate linker for pH-controlled release of diosgenin and two brassinosteroids (DI31 and S7) with agrochemical and potential anticancer activity, is hereby described. Polyphosphazenes carrying approximately 17 wt% of DI31 or S7 self-assembled
本文描述了基于亲水性聚环氧烷Jeffamine M1000和疏水性类固醇与甘氨酸酯连接基的新型聚磷腈纳米载体的合成与表征,该疏水性类固醇具有可控制pH的薯os皂苷元和两种具有农药化学和潜在抗癌活性的油菜素类固醇(DI31和S7)的pH。携带约17 wt%的DI31或S7的聚磷腈在水中自组装形成120-150 nm的纳米聚集体,由于在4天后持续输送了约30%的农药,因此对萝卜子叶显示出优异的植物生长效果。细胞毒性评估显示,所有携带类固醇和Jeffamine M1000的聚合物均会对MCF-7癌细胞产生强至中度毒性,并且在0.1至0.025 mg mL -1下对人原代肺成纤维细胞无毒。因此,以10 -4至10 -6 mg mL -1施用的含DI31和S7的聚合物向作物交付建议的DI31或S7量应对人类无害。特别是,带有DI31和S7的聚合物对MCF-7具有很强的细胞毒性,对人类原代肺成纤维细胞