Room Temperature Coupling of Aryldiazoacetates with Boronic Acids Enhanced by Blue Light Irradiation
作者:Amanda F. Silva、Marco A. S. Afonso、Rodrigo A. Cormanich、Igor D. Jurberg
DOI:10.1002/chem.201905812
日期:2020.5.4
visible-light-promoted photochemical protocol is reported for the coupling of aryldiazoacetates with boronic acids. This photochemicalreaction shows great enhancement compared to the same protocol performed in the absence of light. Except for a few cases, the room temperature coupling in the dark (thermal process) generally does not work. When it does, it is likely to also involve free carbenes as key intermediates
diazoacetates with cysteine residues that enabled metal‐free, S−H functionalization under visible‐light conditions. Moreover, this process could be intensified by a continuous‐flow photomicroreactor on the acceleration of the reaction (6.5 min residence time). The batch and flow protocols described were applied to obtain a wide range of functionalized cysteine derivatives and cysteine‐containing dipeptides
Aminopalladation-Triggered Carbene Insertion Reaction: Synthesis of 2-(1<i>H</i>-Indol-3-yl)acetates
作者:Ziwei Hu、Shuang Luo、Qiang Zhu
DOI:10.1002/adsc.201400799
日期:2015.3.23
red carbeneinsertionreaction for the synthesis of C‐3 alkylated indole derivatives from ortho‐alkynyltrifluoroacetanilides and α‐diazoacetates is presented; it involves a palladium catalyst and a weak base in the open air. Yields range from 49–88% with excellent functional group tolerance. The reaction proceeds through intramolecular aminopalladation of alkynes followed by carbeneinsertion. Migratory
Sequential C–H Functionalization Reactions for the Enantioselective Synthesis of Highly Functionalized 2,3-Dihydrobenzofurans
作者:Hengbin Wang、Gang Li、Keary M. Engle、Jin-Quan Yu、Huw M. L. Davies
DOI:10.1021/ja401731d
日期:2013.5.8
The enantioselectivesynthesis of 2,3-dihydrobenzofurans was achieved by using two sequential C-H functionalizationreactions, a rhodium-catalyzed enantioselective intermolecular C-H insertion followed by a palladium-catalyzed C-H activation/C-O cyclization. Further diversification of the 2,3-dihydrobenzofuran structures was possible by a subsequent palladium-catalyzed intermolecular Heck-type sp(2)
Blue light-promoted N–H insertion of amides, isatins, sulfonamides and imides into aryldiazoacetates: Synthesis of unnatural α-aryl amino acid derivatives
作者:Celso Y. Okada、Caio Y. dos Santos、Igor D. Jurberg
DOI:10.1016/j.tet.2020.131316
日期:2020.12
A photochemical protocol using blue light allows the N–H insertion of amides, isatins, sulfonamides and imides into aryldiazoacetates to afford the corresponding α-amino esters. This method is experimentally simple, inexpensive and tolerates numerous functional groups, thus allowing the straightforward preparation of a variety of α-aryl amino acid derivatives in good yields.