芳基碘化物和溴化物与丙烯醛二乙缩醛在Pd(OAc)(2),(n)()Bu(4)NOAc,K(2)CO(3),KCl和DMF存在下的反应,于90直至乙缩醛消失,然后向粗制反应混合物中加入2 N HCl,可以得到高至高收率的肉桂醛。芳基卤化物中可耐受多种官能团,包括醚,醛,酮,酯,二烷基氨基,腈基和硝基。靠近氧化加成位点的取代基的存在不妨碍反应。
Heck Reactions of Acrolein or Enones and Aryl Bromides – Synthesis of 3‐Aryl Propenals or Propenones and Consecutive Application in Multicomponent Pyrazole Syntheses
作者:Marvin Stephan、Jesco Panther、Fabio Wilbert、Pauline Ozog、Thomas J. J. Müller
DOI:10.1002/ejoc.202000066
日期:2020.4.16
The Heck reaction of (hetero)aryl bromides and acrolein or vinyl ketones using CataCXium® Ptb as a ligand, NaHCO3 as a base, and nBu4NCl provides an efficient access to 3‐(hetero)aryl propenals/propenones, which are directly employed in consecutive multicomponent syntheses of pyrazoles in a one‐pot fashion.
使用CataCXium®Ptb作为配体,NaHCO 3作为碱和n Bu 4 NCl进行(杂)芳基溴化物和丙烯醛或乙烯基酮的Heck反应,可以有效地获得3-(杂)芳基丙烯/丙烯酮。以单罐方式直接用于吡唑的连续多组分合成中。
Iridium-catalyzed alkenyl C–H allylation using conjugated dienes
An iridium-catalyzed C–H allylation of acrylamides with conjugated dienes was developed, using NH-Ts amide as the directing group. The ligand- and additive-free protocol provided a convenient and atom economic synthesis of branched 1,4-diene skeletons, enabling the tolerance of a wide scope of functionalities such as OMe, F, Cl, Br and CF3. The utility of this protocol is also demonstrated by a preparative
A practical and atom-economic protocol for the stereoselective preparation of various 1,4- and 1,3-diene skeletons through iridium-catalyzed directed olefinic C–H allylation and alkenylation of NH-Ts acrylamides in water was developed. This reaction tolerated a wide scope of substrates under simple reaction conditions and enabled successful gram-scale preparation. Furthermore, an asymmetric variant
Organocatalyzed oxidative N-annulation for diverse and polyfunctionalized pyridines
作者:Hari Datta Khanal、Yong Rok Lee
DOI:10.1039/c5cc01807b
日期:——
A variety of polyfunctionalized pyridines were synthesized from readily available ketones with α,β-unsaturated aldehydes and ammonium acetate under a mild organocatalyst.
Multicomponent synthesis of styryl linked benzo[<i>h</i>]pyrazolo[3,4-<i>b</i>]quinoline-5,6(10<i>H</i>)-diones by liquid assisted grinding
作者:Rahul Yadav、Tasneem Parvin
DOI:10.1039/d1nj00770j
日期:——
Herein we report an interesting multicomponent reaction of α,β-unsaturated aldehydes, 2-hydroxy-1,4-naphthoquinone and 5-aminopyrazoles by liquid assisted grinding.