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。
Synthesis and oxidation catalysis of a Ti-substituted phosphotungstate, and identification of the active oxygen species
report the synthesis of a Ti-substituted phosphotungstate, TBA6[(γ-PW10O36)2Ti4(μ-O)2(μ-OH)4] (I, TBA = tetra-n-butylammonium), and its application to H2O2-based oxidation. Firstly, an organic solvent-soluble dilacunary phosphotungstate precursor, TBA3[γ-PW10O34(H2O)2] (PW10), has been synthesized. By the reaction of PW10 and TiO(acac)2 (acac = acetylacetonate) in an organic medium (acetonitrile), I can
Vanadium (IV) complexes with Schiff base ligands derived from 2,3-diaminopyridine as catalyst for the oxidation of sulfides to sulfoxides with H2O2
作者:Abedien Zabardasti、Sayed Asad Shangaie
DOI:10.1007/s13738-018-1480-2
日期:2019.1
(IV) complexes with Schiff base ligands derivedfrom 2,3-diaminopyridine were used to as catalyst for the oxidation of sulfides to sulfoxides with H2O2. To the most of our information, there is not any literature description on the selective oxidation of sulfides to sulfoxides by means of a vanadium (IV) Schiff base complex with N, O donor ligand derivedfrom 2,3-diaminopyridine catalyst beneath these
亚砜是用于合成有价值的配合物和用作药物的物质。在适度的条件下,用冰醋酸作为催化剂,在溶剂的作用下,使用钒(IV)Schiff碱络合物,用(H 2 O 2)过氧化氢将硫化物选择性地氧化为相应的亚砜,生成适当的收率。为了将硫化物转化为各种催化剂的亚砜。必须注意的是,在我们之前的文章中,钒基络合物(VOY 1合成的)用作苯乙烯的环氧化催化剂(Zabardasti和Shangaie,J Iran Chem Soc 13:1875-1886,2016),但在新工作中,钒(IV)与具有2,3的席夫碱配体的配合物使用二氨基吡啶作为催化剂,将硫化物与H 2 O 2氧化为亚砜。据我们所知,没有关于在这些条件下通过钒(IV)Schiff碱与N,O供体配体衍生自2,3-二氨基吡啶催化剂的硫化物选择性氧化为亚砜的文献的描述。选择二甲基硫作为优化实验的图案底物。硫化物的氧化作用在25°C的温度下起作用,其中催化量的钒(IV)络合物或(VOY
Dynamic Kinetic Resolution of Allylic Sulfoxides by Rh-Catalyzed Hydrogenation: A Combined Theoretical and Experimental Mechanistic Study
作者:Peter K. Dornan、Kevin G. M. Kou、K. N. Houk、Vy M. Dong
DOI:10.1021/ja409824b
日期:2014.1.8
with catalytic asymmetric hydrogenation. The efficiency of our DKR was optimized by using low pressures of hydrogen gas to decrease the rate of hydrogenation relative to the rate of sigmatropic rearrangement. Kinetic studies reveal that the rhodium complex acts as a dual-role catalyst and accelerates the substrate racemization while catalyzing olefin hydrogenation. Scrambling experiments and theoretical
Fe 2 O 3 -catalyzed Pummerer rearrangement of acyl chlorides and sulfoxides: Facile synthesis of alkylthiomethyl ester
作者:Haotian Xing、Long Chen、Yimin Jia、Zhongxing Jiang、Zhigang Yang
DOI:10.1016/j.tetlet.2017.04.053
日期:2017.6
A simple, effective approach for the Pummererrearrangement of acyl chlorides with sulfoxides by using a low-cost and more abundant Fe catalyst has been described. The alkylthiomethyl ester products were prepared in good to excellent yields for a range of different substrates including asymmetrical sulfoxides and acyl chlorides with a variety of functional groups under mild reaction conditions. The