More Like this

1. Asymmetric Synthesis of P-Stereogenic Secondary Phosphine ­Oxides (SPOs)

   https://doi.org/10.1055/a-1582-0169  

   Glueck, David S. (January 2022, Synthesis)

   Abstract P-Stereogenic secondary phosphine oxides [SPOs, RR′P(O)H], valuable ligands for metal complexes in asymmetric catalysis, are also building blocks for other chiral phosphorus derivatives. This short review summarizes methods used for asymmetric synthesis of P-stereogenic SPOs. 1 Introduction 2 Configurational Stability of P-Stereogenic SPOs 3 Classical Resolution, HPLC Separation, and Dynamic Resolution 4 Synthesis via Chiral Auxiliaries 5 Kinetic Resolution 6 Conclusions and Outlook 

   more » « less
2. Brønsted acid and Pd–PHOX dual-catalysed enantioselective addition of activated C-pronucleophiles to internal dienes

   https://doi.org/10.1039/c9sc00633h  

   Park, Sangjune; Adamson, Nathan J.; Malcolmson, Steven J. (May 2019, Chemical Science)

   We describe the development of Pd–PHOX-catalysed enantioselective couplings of internal dienes with malononitrile and other activated C-pronucleophiles. Reactions are dramatically accelerated by the addition of Et 3 N·HBAr F 4 as a Brønsted acid co-catalyst, enabling a suite of products bearing a variety of alkyl substituents at the stereogenic carbon to be prepared. A series of mechanism-oriented experiments reveal key aspects of the catalytic cycle and the importance of the non-coordinating BAr F 4 counterion in not only promoting reactions of internal dienes but also additions of previously unreactive nucleophiles towards terminal dienes. 

   more » « less
3. Combinatorial Ligand Assisted Simultaneous Control of Axial and Central Chirality in Highly Stereoselective C−H Allylation

   https://doi.org/10.1002/anie.202310112  

   Bhattacharya, Trisha; Ghosh, Supratim; Dutta, Subhabrata; Guin, Srimanta; Ghosh, Animesh; Ge, Haibo; Sunoj, Raghavan B; Maiti, Debabrata (January 2024, Angewandte Chemie International Edition)

   Abstract The significance of stereoselective C−H bond functionalization thrives on its direct application potential to pharmaceuticals or complex chiral molecule synthesis. Complication arises when there are multiple stereogenic elements such as a center and an axis of chirality to control. Over the years cooperative assistance of multiple chiral ligands has been applied to control only chiral centers. In this work, we harness the essence of cooperative ligand approach to control two different stereogenic elements in the same molecule by atroposelective allylation to synthesize axially chiral biaryls from its racemic precursor. The crucial roles played by chiral phosphoric acid and chiral amino acid ligand in concert helped us to obtain one major stereoisomer out of four distinct possibilities. 

   more » « less
4. Ni- and Pd-Catalyzed Enantioselective 1,2-Dicarbofunctionalization of Alkenes

   https://doi.org/10.1055/a-2108-9549  

   Kang, Taeho; Apolinar, Omar; Engle, Keary M (December 2023, Synthesis)

   Abstract Catalytic enantioselective 1,2-dicarbofunctionalization (1,2-DCF) of alkenes is a powerful transformation of growing importance in organic synthesis for constructing chiral building blocks, bioactive molecules, and agrochemicals. Both in a two- and three-component context, this family of reactions generates densely functionalized, structurally complex products in a single step. Across several distinct mechanistic pathways at play in these transformations with nickel or palladium catalysts, stereocontrol can be obtained through tailored chiral ligands. In this Review we discuss the various strategies, mechanisms, and catalysts that have been applied to achieve enantioinduction in alkene 1,2-DCF. 1 Introduction 2 Two-Component Enantioselective 1,2-DCF via Migratory Insertion 3 Two-Component Enantioselective 1,2-DCF via Radical Capture 4 Three-Component Enantioselective 1,2-DCF via Radical Capture 5 Three-Component Enantioselective 1,2-DCF via Migratory Insertion 6 Miscellaneous Mechanisms 7 Conclusion 

   more » « less
5. Short Enantioselective Formal Synthesis of (–)-Platencin

   https://doi.org/10.1055/s-0037-1610437  

   Defieber, Christian; Mohr, Justin; Grabovyi, Gennadii; Stoltz, Brian (November 2018, Synthesis)

   A short enantioselective formal synthesis of the antibiotic natural product platencin is reported. Key steps in the synthesis include enantioselective decarboxylation alkylation, aldehyde/olefin radical cyclization, and regioselective aldol cyclization. 

   more » « less