Selective reduction of acyl aziridines to Mannich bases using silyllithium reagents
摘要:
Mannich bases are prepared from the selective alpha-reduction of acyl aziridines using silyllithium reagents. The reaction proceeds via an aziridine ring-opening assisted Brook rearrangement. (C) 2013 Elsevier Ltd. All rights reserved.
Fe(OTf) 3 -catalyzed tandem Meyer-Schuster rearrangement/intermolecular hydroamination of 3-aryl propargyl alcohols for the synthesis of acyclic β-Aminoketones
作者:Ruiheng Tao、Yan Yin、Yongbin Duan、Yuxing Sun、Yue Sun、Fengkai Cheng、Jinpeng Pan、Cheng Lu、Yuan Wang
DOI:10.1016/j.tet.2017.02.030
日期:2017.3
Fe(OTf)3-catalyzed synthesis of acyclic β-aminoketones from 3-aryl propargyl alcohols and nitrogen nucleophiles were investigated. Results showed that propargyl alcohols without bulky groups α to the hydroxyl group underwent the transformation smoothly. Sulphonamides exhibited the higher reactivity than amides as the nitrogen nucleophiles and the transformation of acyclic β-aminoketones were finished
A reaction mixture of β,γ-unsaturatedketone and BF 3 .OEt 2 in CH 3 OH was stirred at room temperature and β-methoxy ketone was produced in high yield. The β-amino ketone was obtained as the major product from a reaction mixture of β,γ-unsaturatedketone, AlCl 3 and Ts-NH 2 in CH 2 Cl 2 at room temperature. This Lewis acid promoted β-substitution reaction mechanism was proposed as that the process
which allows functionalization to occur exclusively at the β-position of ketones. The substrate scope includes a wide range of cycloalkanols as well as diverse N, O, C, and P-centered nucleophiles, providing ready access to β-functionalized ketones as products. Mechanistic studies support the generation of α,β-unsaturated ketones as key intermediates followed by Michael addition with nucleophiles.
已经研究了环烷醇与亲核试剂的电化学解构官能化,这使得官能化只发生在酮的β-位。底物范围包括范围广泛的环烷醇以及各种以 N、O、C 和 P 为中心的亲核试剂,可方便地使用 β-官能化酮作为产品。机理研究支持生成 α,β-不饱和酮作为关键中间体,然后与亲核试剂进行迈克尔加成。
Catalytic Conjugate Additions of Nitrogen-, Phosphorus-, and Carbon-Containing Nucleophiles by Amphoteric Vanadyl Triflate
作者:Yow-Dzer Lin、Jun-Qi Kao、Chien-Tien Chen
DOI:10.1021/ol702302y
日期:2007.12.1
A series of carbamates, amides, N-tosyl amides, (hetero)arenes, and hydrogen phosphines/phosphites has been examined as nucleophiles for (hetero)Michael-type additions to enones and enamides catalyzed by amphoteric vanadyl triflate under mild and neutral conditions. The newly developed C-N, C-P, and C-C bond-formation protocols were carried out smoothly in good to high yields without intervention of any 1,2-additions.