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。
作者:Andrew Whyte、Katherine I. Burton、Jingli Zhang、Mark Lautens
DOI:10.1002/anie.201808460
日期:2018.10.15
An enantioselective copper‐catalyzed intramolecular borylacylation is reported. The reaction proceeds through an initial enantioselective borylcupration of the styrene, followed by a nucleophilic attack on the tethered carbamoyl chloride. The products, chiral borylated 3,3‐disubstituted oxindoles, were generated in excellent yields and enantioselectivities. The versatile carbon–boron bond provides
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
Synthesis of 1-Amino-2,2,2-trifluoroalkylphosphonates from Alkene-Tethered Trifluoroacetimidoyl Chlorides
作者:José F. Rodríguez、Anji Zhang、Ramon Arora、Mark Lautens
DOI:10.1021/acs.orglett.1c02750
日期:2021.10.1
The reaction of alkene-tethered trifluoroacetimidoylchlorides with trialkylphosphites furnishes 1-amino-2,2,2-trifluoroalkylphosphonates. The products were generated in moderate to good yields, and the scalability of this process was showcased. Partial hydrolysis of the phosphonate moiety was achieved. The cyclization is proposed to occur via formation of an imidoyl phosphonate intermediate that
The 1,4-nickel migration process from aryl to alkenyl groups is now reported for the first time. The alkenyl nickel intermediates generated by this highly stereoselective migration process can be coupled with brominated alkanes to form multisubstituted olefins. The current method provides a new and efficient approach for the synthesis of Z/E olefins with high stereoselectivity.
A novel C–N coupling of various arylamines with dialkyl azodicarboxylates under metal-free conditions for the rapid assembly of carbamates has been achieved. This established protocol features mild reaction conditions, simple operation, broad substrate scope, moderate to excellent yields and good tolerance of functional groups. Moreover, the potential synthetic utility of products was exemplified by