Chemical Science, Journal Year: 2023, Volume and Issue: 14(23), P. 6393 - 6398
Published: Jan. 1, 2023
A highly enantioselective cobalt-catalyzed desymmetrizing reductive cyclization of alkynyl cyclodiketones has been developed by employing HBpin as a reducing agent and ferrocene-based PHOX chiral ligand.
Language: Английский
Chemical Reviews, Journal Year: 2024, Volume and Issue: 124(9), P. 6078 - 6144
Published: April 17, 2024
Alcohols are abundant and attractive feedstock molecules for organic synthesis. Many methods their functionalization require them to first be converted into a more activated derivative, while recent years have seen vast increase in the number of complexity-building transformations that directly harness unprotected alcohols. This Review discusses how transition metal catalysis can used toward this goal. These broadly classified three categories. Deoxygenative functionalizations, representing derivatization C–O bond, enable alcohol act as leaving group formation new C–C bonds. Etherifications, characterized by O–H represent classical reactivity has been modernized include mild reaction conditions, diverse partners, high selectivities. Lastly, chain reactions described, wherein acts mediator formal C–H alkyl backbone. Each these classes transformation will discussed context intermolecular arylation, alkylation, related reactions, illustrating alcohols harnessed
Language: Английский
Citations
39
Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(50), P. 23001 - 23009
Published: Dec. 8, 2022
A new regio- and stereoselective reductive coupling of alkynes crotononitrile has been developed via visible light organophotoredox cobalt dual catalysis. variety enantioenriched homoallylic nitriles bearing a stereodefined trisubstituted alkene have easily synthesized with good to excellent (up >20:1 rr), stereo- (>20:1 E/Z), enantioselectivity 98% ee) control under mild conditions. The corresponding nitrile products were smoothly converted into various chiral building blocks. Remarkably, simple organic base together water utilized as hydrogen sources in this photoinduced reaction.
Language: Английский
Citations
40
Nature Chemistry, Journal Year: 2023, Volume and Issue: 16(3), P. 398 - 407
Published: Dec. 11, 2023
Language: Английский
Citations
32
Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 62(1)
Published: Sept. 30, 2022
A visible light-induced Co-catalyzed highly regio- and stereoselective reductive coupling of vinyl azaarenes alkynes has been developed. Notably, Hünig's base together with simple ethanol successfully applied as the hydrogen sources instead commonly used Hantzsch esters in this catalytic photoredox reaction. This approach considerable advantages for straightforward synthesis stereodefined multiple substituted alkenes bearing an azaarene motif, such excellent regioselectivity (>20 : 1 >30 examples) stereoselectivity E/Z), broad substrate scope good functional group compatibility under mild reaction conditions, which utilized concise natural product monomorine I. reasonable pathway involving protolysis cobaltacyclopentene intermediate proposed based on mechanistic studies.
Language: Английский
Citations
36
Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(37), P. 20152 - 20157
Published: Sept. 11, 2023
Transition-metal-catalyzed reductive coupling reactions of alkynes and imines are attractive methods for the synthesis chiral allylic amines. Mechanistically, these involve oxidative cyclization alkyne imine to generate a metallacyclic intermediate, which then reacts with H2 or surrogate form product. As an alternative this hydrogenolysis pathway, here we show that transmetalation zinc can occur, forming metallacycle This organozinc product serves as versatile nucleophile carbon-carbon carbon-heteroatom reactions. Mechanistic studies based on isotopic labeling experiments DFT calculations suggest key step occurs between Co(II) species ZnCl2.
Language: Английский
Citations
18
Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(33)
Published: May 31, 2024
Catalytic enantioselective alkenylation of aldehydes with easily accessible alkenyl halides promoted by a chiral cobalt complex derived from newly developed tridentate bisoxazolinephosphine is presented. Such processes represent an unprecedented reaction pathway for catalysis and general approach that enable rapid construction highly diversified enantioenriched allylic alcohols containing 1,1-, 1,2-disubstituted trisubstituted alkene as well axial stereogenicity in up to 99 % yield : 1 er without the need preformation alkenyl-metal reagents. DFT calculations revealed origin enantioselectivity.
Language: Английский
Citations
9
ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(4), P. 2202 - 2206
Published: Jan. 26, 2024
Continuous-flow hydrogenations provide greatly improved reaction efficiency due to the efficient mass-transfer between heterogeneous catalysts and hydrogen gas. However, reported flow were limited only simple functional group transformations, development of sophisticated catalysis such as enantioselective reductive C–C bond formations remains challenging. Herein, we have developed continuous-flow cyclization 1,6-enynes using chiral supported on heteropoly acid/amine-functionalized SiO2 composites in our group. Investigations under conditions revealed that tuning structure acids amines could improve catalyst performance. A variety substrates produce products with high yields enantioselectivities optimized without leaching Rh catalyst. Mechanistic studies cause deactivation this transformation.
Language: Английский
Citations
8
Chemical Science, Journal Year: 2022, Volume and Issue: 13(43), P. 12625 - 12633
Published: Jan. 1, 2022
Ruthenium-catalyzed hydrogen auto-transfer reactions for the direct enantioselective conversion of lower alcohols to higher are surveyed. A brief historical perspective on ruthenium-catalyzed transfer is given.
Language: Английский
Citations
27
ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(20), P. 13540 - 13560
Published: Oct. 6, 2023
Bidentate P,N ligands, integrating phosphine and nitrogen donors, are highlighted for their versatile characteristics, offering both electronic steric tunability. Their hemilabile nature, coupled with the ability to modulate properties through choice of donor atoms substituents, has expanded horizons chemical transformations. This Review focuses on Ni-catalyzed cross-coupling reactions mediated by ligands. The asymmetrical nature each atom playing a specific role in catalytic cycle, offers control, stability, unique regioselectivity processes. In particular, Ni/P,N-catalytic system exhibits remarkable reactivity π-substrates including alkenes, alkynes, allenes. A thorough mechanistic understanding these processes insights into trends future directions Ni/P,N-catalyzed reactions.
Language: Английский
Citations
15
Synthesis, Journal Year: 2023, Volume and Issue: 55(10), P. 1487 - 1496
Published: Feb. 20, 2023
Abstract The evolution of methods for carbonyl allylation and crotylation alcohol proelectrophiles culminating in the design iodide-bound ruthenium-JOSIPHOS catalysts is prefaced by a brief historical perspective on asymmetric its relevance to polyketide construction. Using gaseous allene or butadiene as precursors allyl- crotylruthenium nucleophiles, respectively, new capabilities have been unlocked, including stereo- site-selective 1,3-diols related polyols. 1 Introduction Historical Perspective 2 Ruthenium-Catalyzed Conversion Lower Alcohols into Higher 3 Conclusion Future Outlook
Language: Английский
Citations
14