Ureate Titanium Catalysts for Hydroaminoalkylation: Using Ligand Design to Increase Reactivity and Utility
作者:Manfred Manßen、Danfeng Deng、Cameron H. M. Zheng、Rebecca C. DiPucchio、Dafa Chen、Laurel L. Schafer
DOI:10.1021/acscatal.1c00014
日期:2021.4.16
earth-abundant and cost-efficient titanium catalyst generated in situ using commercially available Ti(NMe2)4 and a simple to synthesize urea proligand. This system demonstrates high TOFs for hydroaminoalkylation with unactivated substrates and features easy to use commercially available titanium amido precursors. Additionally, a high catalytic activity, scope of reactivity, and regioselectivity are all demonstrated
Catalytic and Atom-Economic Csp3
−Csp3
Bond Formation: Alkyl Tantalum Ureates for Hydroaminoalkylation
作者:Rebecca C. DiPucchio、Sorin-Claudiu Roşca、Laurel L. Schafer
DOI:10.1002/anie.201712668
日期:2018.3.19
achieved by rapid C−H alkylation of unprotected secondary arylamines with unactivated alkenes. The combination of Ta(CH2SiMe3)3Cl2, and a ureate N,O‐chelating‐ligand salt gives catalytic systems prepared in situ that can realize high yields of β‐alkylated aniline derivatives from either terminal or internal alkene substrates. These new catalyst systems realize C−H alkylation in as little as one hour
Fast Titanium‐Catalyzed Hydroaminomethylation of Alkenes and the Formal Conversion of Methylamine
作者:Jens Bielefeld、Sven Doye
DOI:10.1002/anie.202001111
日期:2020.4.6
The scientific interest in catalytic hydroaminoalkylation reactions of alkenes has vastly increased over the past decade, but these reactions have struggled to become a viable option for general laboratory or industrial use because of reaction times of several days. The titanium-based catalytic system introduced in this work not only reduces the reaction time by several orders of magnitude, into the
[Ind<sub>2</sub>TiMe<sub>2</sub>]: A Catalyst for the Hydroaminomethylation of Alkenes and Styrenes
作者:Raphael Kubiak、Insa Prochnow、Sven Doye
DOI:10.1002/anie.200906557
日期:2010.3.29
Metal‐catalyzed hydroaminomethylations of styrenes, which take place by CH bond activation, can be achieved in the presence of the catalyst [Ind2TiMe2] (Ind=η5‐indenyl). Corresponding reactions of 1‐alkenes with N‐methylanilines performed at temperatures between 80 °C and 105 °C usually take place with regioselectivities of better than 99:1 in favor of the branched product.
Solid-State NMR and DFT Studies on the Formation of Well-Defined Silica-Supported Tantallaaziridines: From Synthesis to Catalytic Application
作者:Bilel Hamzaoui、Jérémie D. A. Pelletier、Edy Abou-Hamad、Yin Chen、Mohamed El Eter、Edrisse Chermak、Luigi Cavallo、Jean-Marie Basset
DOI:10.1002/chem.201504439
日期:2016.2.24
Single‐site, well‐defined, silica‐supported tantallaaziridine intermediates [≡Si‐O‐Ta(η2‐NRCH2)(NMe2)2] [R=Me (2), Ph (3)] were prepared from silica‐supported tetrakis(dimethylamido)tantalum [≡Si‐O‐Ta(NMe2)4] (1) and fully characterized by FTIR spectroscopy, elemental analysis, and 1H,13C HETCOR and DQ TQ solid‐state (SS) NMR spectroscopy. The formation mechanism, by β‐H abstraction, was investigated