多官能化芳烃是众多生物活性天然产物和药物中不可替代的一部分。过渡金属催化的直接不对称双或多CH键官能化是非常可取的,但探索较少。在此,我们开发了一种 Rh(III) 催化的不对称 C H 烯基化环化/酰胺化反应与带有O的烯烃系链芳烃的反应,能够在一个步骤中提供多种呋喃喹唑啉酮,具有广泛的底物范围和良好的官能团耐受性。
Dioxazolones as masked ester surrogates in the Pd(<scp>ii</scp>)-catalyzed direct C–H arylation of 6,5-fused heterocycles
作者:Paridhi Saxena、Neha Maida、Manmohan Kapur
DOI:10.1039/c9cc05563k
日期:——
simple and effective Pd(II)-catalyzed regioselectiveC(2)–H arylation of 6,5-fused heterocycles with dioxazolones as a masked ester surrogate undermildconditions is reported. The significance of the arylation is highlighted by the new reactivity demonstrated in dioxazolones via proximal C–H activation of the cyclic carbonate of the hydroxamic acid functionalityunder protic conditions.
A cobalt(III)-catalyzed C-8 selective C–H amidation of quinoline N-oxide using dioxazolone as an amidating reagentundermildconditions is disclosed. The reaction proceeds efficiently with excellent functional group compatibility. The utility of the current method is demonstrated by gram scale synthesis of C-8 amide quinoline N-oxide and by converting this amidated product into functionalized quinolines
hydroalkylamination and hydroamidation of styrenes have been developed by NiH catalysis with a simple bioxazoline ligand under mild conditions. A wide range of enantioenriched benzylic arylamines, alkylamines and amides can be easily accessed by nitroarenes, hydroxylamines and dioxazolones, respectively as amination reagents. The chiral induction in these reactions is proposed to proceed through an enantiodifferentiating
Cp*Co(III)-catalyzed C H amidation of azines with dioxazolones
作者:Yanzhen Huang、Chao Pi、Zhen Tang、Yangjie Wu、Xiuling Cui
DOI:10.1016/j.cclet.2020.08.046
日期:2020.12
Abstract Cp*Co(III)-catalyzed direct C H amidation of azines has been developed. This conversion could proceed smoothly in the absence of external oxidants, acids or bases, with excellent regioselectivity and broad functional group tolerance. CO2 was released as the sole byproduct, thus providing an environmentally benign amidation process. The products obtained are important intermediates in organic
The Direct Rh(III)-Catalyzed C–H Amidation of Aniline Derivatives Using a Pyrimidine Directing Group: The Selective Solvent Controlled Synthesis of 1,2-Diaminobenzenes and Benzimidazoles
作者:Shrikant M. Khake、Naoto Chatani
DOI:10.1021/acs.orglett.0c01126
日期:2020.5.1
The regioselective Rh(III)-catalyzed C-Hamidation of aniline derivatives with dioxazolones as an amidating reagent with a pyrimidine as a directing group leading to the production of 1,2-diaminobenzene derivatives or benzimidazole derivatives is described. The product distribution is controlled by the nature of solvent used. The reaction provides a broad substrate scope for aniline derivatives with