二苯并[ b , f ][1,5]二氮杂辛是一类八元杂环化合物,具有独特的刚性鞍状结构并具有固有的手性。在这项研究中,我们报告了一种方便、直接的方法,通过手性磷酸催化 2-酰基苯并异氰酸酯的二聚,催化对映选择性合成这些独特的手性分子。值得注意的是,添加相应的2-酰基苯胺作为助催化剂显着提高了这些反应的效率,并且简单的相分离操作导致产物具有优异的对映体纯度。进行实验研究是为了阐明这些反应背后的机制,并根据研究结果提出合理的反应机制。
The Pd‐catalyzed direct arylation of 2,1‐benzisoxazole with arylbromides to access 3‐arylbenzoisoxazoles proceeds in moderate‐to‐high yields with 1 mol % Pd(OAc)2 or 2 mol % PdCl(C3H5)(dppb) (dppb=1,4‐bis(diphenylphosphino)butane) as the catalysts and KOAc as an inexpensive base. A wide variety of (hetero)arylbromides have been employed successfully. Moreover, arylations followed by benzisoxazole
Pd催化2,1-苯并恶唑与芳基溴的直接芳基化反应以生成3-芳基苯并异恶唑,其产率为中至高,产率为1 mol%Pd(OAc)2或2 mol%PdCl(C 3 H 5)(dppb )(dppb = 1,4-双(二苯基膦基)丁烷)作为催化剂,KOAc作为便宜的碱。已经成功地使用了各种各样的(杂)芳基溴化物。此外,芳基化反应后再开苯并异恶唑开环,仅需两个步骤即可制备2-氨基二苯甲酮。
1-(2′-Anilinyl)prop-2-yn-1-ol Rearrangement for Oxindole Synthesis
作者:Prasath Kothandaraman、Bing Qin Koh、Taweetham Limpanuparb、Hajime Hirao、Philip Wai Hong Chan
DOI:10.1002/chem.201202606
日期:2013.2.4
on NIS (N‐iodosuccinimide)‐mediated cycloisomerization reactions of 1‐(2′‐anilinyl)prop‐2‐yn‐1‐ols to gem‐3‐(diiodomethyl)indolin‐2‐ones and 2‐(iodomethylene)indolin‐3‐ones has been developed. The reactions were shown to be chemoselective, with secondary and tertiary alcoholic substrates exclusively giving the 3‐ and 2‐oxindole products, respectively. In the case of the latter, the transformation features
Palladium-catalyzed synthesis of polysubstituted quinolines from 2-amino aromatic ketones and alkynes
作者:Wang Zhou、Jianhua Lei
DOI:10.1039/c4cc00939h
日期:——
A palladium-catalyzed one-pot method for the synthesis of quinolines from commercial or readily available 2-amino aromatic ketones and alkynes is reported for the first time. This transformation offers an alternative method for the synthesis of polysubstituted quinoline.
Synthesis of 3-Sulfonylamino Quinolines from 1-(2-Aminophenyl) Propargyl Alcohols through a Ag(I)-Catalyzed Hydroamination, (2 + 3) Cycloaddition, and an Unusual Strain-Driven Ring Expansion
We describe herein a silver-catalyzed conversion of 1-(2-aminophenyl)-propargyl alcohols to 4-substituted 3-tosylaminoquinolines using TsN3 as an amino surrogate. Controlled reactions reveal the pathway consisting of Ag(I)-catalyzed 5-exo-dig cyclization, catalyst-free (2 + 3) cycloaddition, and ring-expansive rearrangement via nitrogen expulsion. As a support study, we show that the cyclic enamines
I<sub>2</sub>-Catalyzed Aerobic Oxidative C(sp<sup>3</sup>)–H Amination/C–N Cleavage of Tertiary Amine: Synthesis of Quinazolines and Quinazolinones
作者:Yizhe Yan、Ying Xu、Bin Niu、Huifang Xie、Yanqi Liu
DOI:10.1021/acs.joc.5b00474
日期:2015.6.5
An iodine-catalyzedoxidative C(sp3)–H amination/C–N cleavage of tertiaryamines couducted under an oxygen atmosphere has been developed and affords a route to quinazolines and quinazolinones in good to excellent yields via a domino ring annulation. The method is metal-free, peroxide-free, and operationally simple to implement with a wide scope of substrates and represents a new avenue for multiple