Late ‐Stage Peptide Diversification through Cobalt‐Catalyzed C−H Activation: Sequential Multicatalysis for Stapled Peptides
AngewchemLate ‐Stage Peptide Diversification through Cobalt‐Catalyzed C−H Activation: Sequential Multicatalysis for Stapled PeptidesDr. M élanie M. Lorion, Nikolaos Kaplaneris, Dr. Jongwoo Son, Dr. Rositha Kuniyil, Prof. Dr. Lutz Ackermann C −H activation meets metathesis: Bioorthogonal C −H activation of peptides was accomplished by using air‐and moisture‐stable catalysts based on Earth‐abundant cobalt. This reaction set the stage for the combination of C−H functionalization and olefin metathesis to construct complex cyclic peptides. (Source: Organometallic Current)
Source: Organometallic Current - January 10, 2019 Category: Chemistry Tags: C-H Activation Co catalyzed Late Stage Functionalization Pd Catalyzed Peptide Modification Ru catalyzed Source Type: blogs

Rapid Construction of Structurally Diverse Quinolizidines, Indolizidines, and Their Analogues via Ruthenium ‐Catalyzed Asymmetric Cascade Hydrogenation/Reductive Amination
AngewchemRapid Construction of Structurally Diverse Quinolizidines, Indolizidines, and Their Analogues via Ruthenium ‐Catalyzed Asymmetric Cascade Hydrogenation/Reductive AminationYa Chen, Yan ‐Mei He, Shanshan Zhang, Tingting Miao, Prof. Dr. Qing‐Hua FanCascade reaction: A rapid construction of enantioenriched benzo ‐fused quinolizidines, indolizidines, and their analogues by ruthenium‐catalyzed asymmetric cascade hydrogenation/reductive amination of quinolinyl‐ and quinoxalinyl‐containing ketones is described. A range of chiral benzo‐fused aliphaticN‐heterocyclic compounds were obtained in good yields...
Source: Organometallic Current - January 10, 2019 Category: Chemistry Tags: Hydrogenation Reductive Amination Ru catalyzed Source Type: blogs

A Concise Total Synthesis of ( ±)‐Vibralactone
AngewchemA Concise Total Synthesis of ( ±)‐Vibralactone Sepand K. Nistanaki, Luke A. Boralsky, Roy D. Pan, Prof.  Dr. Hosea M. NelsonBringing the housane down: The five ‐step synthesis of (±)‐vibralactone, a biologically active terpenoid natural product, is described. This is the shortest total synthesis of (±)‐vibralactone reported to date. (Source: Organometallic Current)
Source: Organometallic Current - January 10, 2019 Category: Chemistry Tags: Natural products Total synthesis Source Type: blogs

The Combination of Benzaldehyde and Nickel ‐Catalyzed Photoredox C(sp3)−H Alkylation/Arylation
AngewchemThe Combination of Benzaldehyde and Nickel ‐Catalyzed Photoredox C(sp3)−H Alkylation/Arylation M.  Sc. Lumin Zhang, M. Sc. Xiaojia Si, M. Sc. Yangyang Yang, M. Sc. Marc Zimmer, M. Sc. Sina Witzel, Dr. Kohei Sekine, Dr. Matthias Rudolph, Prof. Dr. A. Stephen K. Hashmi A combined approach: A simple and general strategy involving the combination of a photo ‐organocatalyst (benzaldehyde) and a transition‐metal catalyst (nickel) has been developed for the highly selective photoredox C(sp3) −H alkylation/arylation of ethers. A selective late‐stage modification of (−)‐ambroxide has also b...
Source: Organometallic Current - January 10, 2019 Category: Chemistry Tags: Alkylation Arylation Ni Catalyzed Sp3 Functionalization UV light Source Type: blogs

Access to All ‐Carbon Spirocycles through a Carbene and Thiourea Cocatalytic Desymmetrization Cascade Reaction
AngewchemAccess to All ‐Carbon Spirocycles through a Carbene and Thiourea Cocatalytic Desymmetrization Cascade ReactionShitian Zhuo, Tingshun Zhu, Liejin Zhou, Chengli Mou, Huifang Chai, Yunpeng Lu, Lutai Pan, Zhichao Jin, Prof.  Dr. Yonggui Robin Chi Harmony between cats: Dual carbene and thiourea catalysis enabled rapid asymmetric access to spirocyclic compounds by a desymmetrization process (see scheme). The presence of the thiourea cocatalyst was essential for this carbene ‐catalyzed enantioselective synthesis of all‐carbon spirocycles to proceed. The reaction products can be readily transformed into sophi...
Source: Organometallic Current - January 10, 2019 Category: Chemistry Tags: All-Carbon Quaternary centers Desymmetrization Spirocycles Source Type: blogs

Chiral Sulfide Catalysis for Desymmetrizing Enantioselective Chlorination
AngewchemChiral Sulfide Catalysis for Desymmetrizing Enantioselective Chlorination Qingxiang Cao, Jie Luo, Prof.  Dr. Xiaodan Zhao A chiral sulfide catalyzed the desymmetrizing enantioselective chlorination of various aryl ‐tethered diolefins and diaryl‐tethered olefins to afford teralins and tricyclic hexahydrophenalene derivatives, respectively, bearing multiple stereogenic centers. In contrast, the tertiary amine catalyst (DHQD)2PHAL led to a diastereomeric product. The products could be transformed into diverse compounds such as spiro ‐N‐heterocycles. (Source: Organometallic Current)
Source: Organometallic Current - January 10, 2019 Category: Chemistry Tags: Chlorination Desymmetrization Enantioselective organocatalysis Source Type: blogs

Catalyst ‐Controlled 1,2‐ and 1,1‐Arylboration of α‐Alkyl Alkenyl Arenes
AngewchemCatalyst ‐Controlled 1,2‐ and 1,1‐Arylboration of α‐Alkyl Alkenyl ArenesAllison M. Bergmann, Stanna K. Dorn, Kevin B. Smith, Kaitlyn M. Logan Prof. M. Kevin Brown Two methods are reported for the 1,2 ‐ and 1,1‐arylboration of α‐methyl vinyl arenes. In the case of 1,2‐arylboration, the formation of a quaternary center occurred through a rare cross‐coupling reaction of a tertiary organometallic complex. 1,1‐Arylboration was enabled by catalyst optimization and occurred through a β ‐hydride elimination/reinsertion cascade. Enantioselective variants of both processes are presented as well...
Source: Organometallic Current - January 10, 2019 Category: Chemistry Tags: boration Cu catalyzed Pd Catalyzed Source Type: blogs

Palladium ‐Catalyzed Divergent Cyclopropanation by Regioselective Solvent‐Driven C(sp3)−H Bond Activation
AngewchemPalladium ‐Catalyzed Divergent Cyclopropanation by Regioselective Solvent‐Driven C(sp3)−H Bond ActivationDa Sol Chung, Jae Sung Lee, Ho Ryu, Dr. Jiyong Park, Hyunjoong Kim, Joo Hyun Lee, Dr. U Bin Kim, Prof.  Dr. Won Koo Lee, Prof.  Dr. Mu‐Hyun Baik, Prof.  Dr. Sang‐gi LeeA tandem palladium ‐catalyzed Heck/regioselective C(sp3) −H activation reaction for the divergent synthesis of spiro‐ and fused‐cyclopropanated indolines from N‐methallylated 2‐bromoarylamides. The regioselectivity of the C−H bond activation in the σ‐alkylPdII intermediate is controlled by...
Source: Organometallic Current - October 26, 2018 Category: Chemistry Tags: Cyclopropanation Pd Catalyzed sp3 C-H Activation Source Type: blogs