Highly Regioselective Synthesis of Substituted Isoindolinones<i>via</i>Ruthenium-Catalyzed Alkyne Cyclotrimerizations
作者:Robert W. Foster、Christopher J. Tame、Helen C. Hailes、Tom D. Sheppard
DOI:10.1002/adsc.201300055
日期:2013.8.12
uthenium chloride [Cp*RuCl(cod)] has been used to catalyze the regioselective cyclization of amide-tethered diynes with monosubstituted alkynes to give polysubstituted isoindolinones. Notably, the presence of a trimethylsilyl group on the diyne generally led to complete control over the regioselectivity of the alkynecyclotrimerization. The cyclization reaction worked well in a sustainable non-chlorinated
Alkynylboronates and -boramides in CoI- and RhI-Catalyzed [2+2+2] Cycloadditions: Construction of Oligoaryls through Selective Suzuki Couplings
作者:Laura Iannazzo、K. Peter C. Vollhardt、Max Malacria、Corinne Aubert、Vincent Gandon
DOI:10.1002/ejoc.201100371
日期:2011.6
borylated alkynes, followed by Suzuki cross-couplings with aryl halides. Ethynylboryl pinacolate took part in cobalt-catalyzed [2+2+2] cycloadditions of all types investigated (i.e., all-intermolecular cyclotrimerization, diyne-yne cocyclization, and all-intramolecular triyne cycloisomerization). The resulting platforms gave rise to linear and angular ter- and quateraryls after Pd-catalyzed cross-coupling
Ethynyl‐B(dan) in [3+2] Cycloaddition and Larock Indole Synthesis: Synthesis of Stable Boron‐Containing Heteroaromatic Compounds
作者:Jialun Li、Hideya Tanaka、Taiki Imagawa、Takumi Tsushima、Masaaki Nakamoto、Jiajing Tan、Hiroto Yoshida
DOI:10.1002/chem.202303403
日期:2024.2.7
Direct, efficient synthesis of diverse five-membered heteroaryl-B(dan) with excellent protodeborylation-resistant properties has been achieved depending upon [3+2] cycloaddition or Pd-catalyzed heteroannulation of ethynyl-B(dan). The resulting heteroaryl-B(dan) has been demonstrated to undergo direct cross-coupling, regardless of the highly diminished Lewis acidity.
A Boron Activating Effect Enables Cobalt-Catalyzed Asymmetric Hydrogenation of Sterically Hindered Alkenes
作者:Peter Viereck、Simon Krautwald、Tyler P. Pabst、Paul J. Chirik
DOI:10.1021/jacs.9b12214
日期:2020.2.26
8-diaminonaphthalatoboryl) substituent each were hydrogenated in high yield and enantioselectivity using C1-symmetric pyridine(diimine) (PDI) cobalt complexes. High activities and stereoselectivities were observed with an array of 2-alkyl, 2-aryl, and 2-boryl-substituted 1,1-diboryl alkenes, giving rise to enantioenriched diborylalkane building blocks. Systematic study of substrate substituenteffects identified competing