Catalyst Pendent-Base Effects on Cyclization of Alkynyl Amines
作者:James M. Stubbs、Devon E. Chapple、Paul D. Boyle、Johanna M. Blacquiere
DOI:10.1002/cctc.201800713
日期:2018.9.7
A family of [CpRu(PP)(MeCN)]PF6 complexes (2 a–e and 4) were prepared in which the bis‐phosphine ligand contains a pendent tertiary amine in the second‐coordinationsphere. 2 a–e contain PPh2NR′2 ligands with two amine groups as the pendent base. Complex 4 has the PPh2NPh1 ligand with only one pendentamine. The catalytic performance of 2 a–e and 4 were assessed in the cyclization of 2‐ethynyl aniline
制备了一个[CpRu(PP)(MeCN)] PF 6配合物(2 a – e和4),其中双膦配体在第二配位领域包含一个侧基叔胺。2 - ë含有P博士2 Ñ R' 2点具有两个胺基团作为侧基的配体。配合物4具有仅具有一种侧胺的P Ph 2 N Ph 1配体。2 a – e和4的催化性能在2-乙炔基苯胺和2-乙炔基苄醇的环化中进行了评估。已经发现,侧链胺在金属活性位点附近的定位对于高催化剂性能是必不可少的。P的比较博士2 Ñ R' 2种催化剂(2 - ë)显示性能最小差作为侧胺碱度的函数。而是,仅需要阈值碱度(其中的侧链胺比底物更碱性)即可实现高性能。
Divergent Palladium Iodide Catalyzed Multicomponent Carbonylative Approaches to Functionalized Isoindolinone and Isobenzofuranimine Derivatives
作者:Raffaella Mancuso、Ida Ziccarelli、Donatella Armentano、Nadia Marino、Salvatore V. Giofrè、Bartolo Gabriele
DOI:10.1021/jo500281h
日期:2014.4.18
formation of 3-[(dialkylcarbamoyl)methylene]isoindolin-1-ones through the intermediate formation of the corresponding 2-ynamide derivatives followed by intramolecular nucleophilic attack by the nitrogen of the benzamide moiety on the conjugated triple bond. On the other hand, 3-[(alkoxycarbonyl)methylene]isobenzofuran-1(3H)imines were selectively obtained when the oxidative carbonylation of 2-alkynylbenzamides
Abstract Indoles, dihydroisoquinolines, and dihydroquinolines were efficiently prepared by ruthenium-catalyzed heterocyclizations of aromatic homo- and bis-homopropargyl amines/amides in the presence of an amine/ammonium base-acid pair. These regioselective 5-endo and 6-endo cyclizations most probably occur by nucleophilic trapping of key ruthenium-vinylidene intermediates. Indoles, dihydroisoquinolines
Phosphazene Superbase-Mediated Regio- and Stereoselective Iodoaminocyclization of 2-(1-Alkynyl)benzamides for the Synthesis of Isoindolin-1-ones
作者:Saurabh Mehta、Dhirendra Brahmchari
DOI:10.1021/acs.joc.9b00452
日期:2019.5.3
exclusive formation of products with Z-geometry (across the exo C═C bond) has been confirmed through X-raycrystallography. The methodology also provides an easy access to aristolactams, an important class of natural products. This has been successfully demonstrated by synthesizing two aristolactam derivatives (including Cepharanone B).
Regio- and Stereoselective Synthesis of Isoindolin-1-ones through BuLi-Mediated Iodoaminocyclization of 2-(1-Alkynyl)benzamides
作者:Dhirendra Brahmchari、Akhilesh K. Verma、Saurabh Mehta
DOI:10.1021/acs.joc.7b02903
日期:2018.3.16
A simple and straightforward synthesis of isoindolin-1-ones is reported. Exclusive N-cyclization of the amide functional group, an ambident nucleophile, was accomplished for the cyclization of 2-(1-alkynyl)benzamides using n-BuLi-I2/ICl. The methodology works with the primary amide and affords the desired isoindolinones in yields of 38–94%. Interestingly, the isolated products exhibit a Z-stereochemistry