ChemInform Abstract: Metal-Catalyzed Intramolecular Heteroatom (X) → Carbon (C) Functional Group Migration Reactions Involving Additions of X-Y Bonds Across Alkynes

ChemInform ◽  
2010 ◽  
Vol 41 (51) ◽  
pp. no-no
Author(s):  
Nitin T. Patil ◽  
Rahul D. Kavthe ◽  
Yoshinori Yamamoto
Keyword(s):  
Functional Group ◽  
Metal Catalyzed ◽  
Group Migration

Catalytic Enantioselective Benzylation Directly from Aryl Acetic Acids

2018 ◽  
Author(s):  
Patrick Moon ◽  
Zhongyu Wie ◽  
Rylan Lundgren
Keyword(s):  
Functional Group ◽  
Terminal Event ◽  
Radical Intermediates ◽  
Carbon Carbon Bond ◽  
Or Groups ◽  
Reaction Proceeds ◽  
Wide Availability ◽  
Metal Catalyzed ◽  
The Stability ◽  
Acetic Acids

The stability and wide availability of carboxylic acids make them valuable reagents in chemical synthesis. Most transition metal catalyzed processes using carboxylic acid substrates are initiated by a decarboxylation event that generates reactive carbanion or radical intermediates. Developing enantioselective methodologies relying on these principles can be challenging, as highly reactive species tend to react indiscriminately without selectivity. Furthermore, anionic or radical intermediates generated from decarboxylation can be incompatible with protic and electrophilic functionality, or groups that undergo trapping with radicals. We demonstrate that metal-catalyzed enantioselective benzylation reactions of allylic electrophiles can occur directly from aryl acetic acids. The reaction proceeds via a pathway in which decarboxylation is the terminal event, occurring after stereoselective carbon–carbon bond formation. The mechanistic features of the process enable enantioselective benzylation without the generation of a highly basic nucleophile. Thus, the process has broad functional group compatibility that would not be possible employing established protocols.<br>

Asymmetric Synthesis of α-Alkylated γ-Lactam via Nickel/8-Quinim-Catalyzed Reductive Alkyl-Carbamoylation of Unactivated Alkene

Synlett ◽  
2021 ◽  
Author(s):  
Xianqing Wu ◽  
Mohini Shrestha ◽  
Yifeng Chen
Keyword(s):  
Functional Group ◽  
Enantioselective Synthesis ◽  
Chiral Auxiliary ◽  
Alkyl Iodide ◽  
General Strategy ◽  
Chemical Bonds ◽  
Mild Conditions ◽  
Chiral Carbon ◽  
Enantioselective Reaction ◽  
Metal Catalyzed

AbstractChiral-auxiliary-mediated synthesis represents the most frequently used synthetic tool for the induction of chirality on α-position of γ-lactams in organic synthesis. However, the general strategy requires the stoichiometric use of chiral reagents with multiple manipulation steps. Transition-metal-catalyzed asymmetric alkene dicarbofunctionalization using readily available substrates under mild conditions allows the simultaneous construction of two vicinal chemical bonds and a chiral carbon center, hence, gain expedient access to chiral heterocycles. Herein, we disclose a Ni-catalyzed enantioselective reaction of 3-butenyl carbamoyl chloride and primary alkyl iodide enabled by a newly designed chiral 8-quinoline imidazoline ligand (8-Quinim). This protocol features broad functional group tolerance and high enantioselectivities, achieving unprecedented synthesis of chiral nonaromatic heterocycles via catalytic reductive protocol.1 Introduction2 Development of 8-Quinim Ligand3 Nickel/8-Quinim-Catalyzed Enantioselective Synthesis of Chiral α-Alkylated γ-Lactam4 Conclusion and Outlook

scholarly journals Protecting group-free, selective cross-coupling of alkyltrifluoroborates with borylated aryl bromides via photoredox/nickel dual catalysis

2015 ◽  
Vol 112 (39) ◽  
pp. 12026-12029 ◽  
Author(s):  
Yohei Yamashita ◽  
John C. Tellis ◽  
Gary A. Molander
Keyword(s):  
Small Molecules ◽  
Functional Group ◽  
Cross Coupling ◽  
Differential Protection ◽  
Coupling Reactions ◽  
Protecting Group ◽  
Cross Coupling Reactions ◽  
Aryl Bromides ◽  
Rapid Construction ◽  
Metal Catalyzed

Orthogonal reactivity modes offer substantial opportunities for rapid construction of complex small molecules. However, most strategies for imparting orthogonality to cross-coupling reactions rely on differential protection of reactive sites, greatly reducing both atom and step economies. Reported here is a strategy for orthogonal cross-coupling wherein a mechanistically distinct activation mode for transmetalation of sp3-hybridized organoboron reagents enables C-C bond formation in the presence of various protected and unprotected sp2-hybridized organoborons. This manifold has the potential for broad application, because orthogonality is inherent to the activation mode itself. The diversification potential of this platform is shown in the rapid elaboration of a trifunctional lynchpin through various transition metal-catalyzed processes without nonproductive deprotection or functional group manipulation steps.

Metal-catalyzed radical-type transformation of unactivated alkyl halides with C–C bond formation under photoinduced conditions

2019 ◽  
Vol 6 (13) ◽  
pp. 2183-2199 ◽  
Author(s):  
Shengqing Ye ◽  
Tianyi Xiang ◽  
Xiaofang Li ◽  
Jie Wu
Keyword(s):  
Functional Group ◽  
Bond Formation ◽  
Alkyl Halides ◽  
Type Transformation ◽  
Recent Advances ◽  
Metal Catalyzed ◽  
Radical Type

Recent advances in the metal-catalyzed radical-type transformation of unactivated alkyl halides with C–C bond formation under photoinduced conditions are summarized. Usually, a broad reaction scope is observed including tertiary, secondary, and primary alkyl halides, with good functional group compatibility.

scholarly journals Weinreb Amides as Directing Groups for Transition Metal-Catalyzed C-H Functionalizations

Molecules ◽  
2019 ◽  
Vol 24 (5) ◽  
pp. 830 ◽  
Author(s):  
Jagadeesh Kalepu ◽  
Lukasz Pilarski
Keyword(s):  
Transition Metal ◽  
Functional Group ◽  
Metal Catalysts ◽  
Mechanistic Studies ◽  
Weinreb Amides ◽  
Transition Metal Catalyzed ◽  
Metal Catalyzed

Weinreb amides are a privileged, multi-functional group with well-established utility in classical synthesis. Recently, several studies have demonstrated the use of Weinreb amides as interesting substrates in transition metal-catalyzed C-H functionalization reactions. Herein, we review this part of the literature, including the metal catalysts, transformations explored so far and specific insights from mechanistic studies.

Functional group migration in benzaldoxime-O-n-propyl ether radical cation

2002 ◽  
Vol 217 (1-3) ◽  
pp. 153-168 ◽  
Author(s):  
Matthias C Letzel ◽  
Hans-Friedrich Grützmacher ◽  
Thomas Fürst ◽  
Klaus K Mayer ◽  
Wolfgang Wiegrebe
Keyword(s):  
Radical Cation ◽  
Functional Group ◽  
Group Migration

Transition-Metal-Catalyzed Rearrangement of 1,1-(Oligomethylene)-4-aryl-2-butene-1,4-diols: Ring Expansion vs. Aryl Group Migration

Synlett ◽  
2009 ◽  
Vol 2009 (18) ◽  
pp. 2987-2991
Author(s):  
Stefan Kirsch ◽  
Alex Lange ◽  
Wolfgang Heydenreuter ◽  
Helge Menz
Keyword(s):  
Transition Metal ◽  
Ring Expansion ◽  
Aryl Group ◽  
Transition Metal Catalyzed ◽  
Metal Catalyzed ◽  
Group Migration

Functional Group Migration in Ionized Long-Chain Compounds

1994 ◽  
Vol 116 (13) ◽  
pp. 5865-5872 ◽  
Author(s):  
Ilan Vidavsky ◽  
Russell A. Chorush ◽  
Pierre Longevialle ◽  
Fred W. McLafferty
Keyword(s):  
Functional Group ◽  
Chain Compounds ◽  
Group Migration ◽  
Long Chain

Recent Progress in Metal-Catalyzed [2+2+2] Cycloaddition Reactions

Synthesis ◽  
2021 ◽  
Author(s):  
Virginie Ratovelomanana-Vidal ◽  
Pascal Matton ◽  
Steve Huvelle ◽  
Mansour Haddad ◽  
Phannarath Phansavath
Keyword(s):  
Functional Group ◽  
Single Step ◽  
Organometallic Complexes ◽  
Cycloaddition Reactions ◽  
Planar Chirality ◽  
Rapid Construction ◽  
Intramolecular Reactions ◽  
Intermolecular Reactions ◽  
Metal Catalyzed ◽  
Economical Process

AbstractMetal-catalyzed [2+2+2] cycloaddition is a powerful tool that allows rapid construction of functionalized 6-membered carbo- and heterocycles in a single step through an atom-economical process with high functional group tolerance. The reaction is usually regio- and chemoselective although selectivity issues can still be challenging for intermolecular reactions involving the cross-[2+2+2] cycloaddition of two or three different alkynes and various strategies have been developed to attain high selectivities. Furthermore, enantioselective [2+2+2] cycloaddition is an efficient means to create central, axial, and planar chirality and a variety of chiral organometallic complexes can be used for asymmetric transition-metal-catalyzed inter- and intramolecular reactions. This review summarizes the recent advances in the field of [2+2+2] cycloaddition.1 Introduction2 Formation of Carbocycles2.1 Intermolecular Reactions2.1.1 Cyclotrimerization of Alkynes2.1.2 [2+2+2] Cycloaddition of Two Different Alkynes2.1.3 [2+2+2] Cycloaddition of Alkynes/Alkenes with Alkenes/Enamides2.2 Partially Intramolecular [2+2+2] Cycloaddition Reactions2.2.1 Rhodium-Catalyzed [2+2+2] Cycloaddition2.2.2 Molybdenum-Catalyzed [2+2+2] Cycloaddition2.2.3 Cobalt-Catalyzed [2+2+2] Cycloaddition2.2.4 Ruthenium-Catalyzed [2+2+2] Cycloaddition2.2.5 Other Metal-Catalyzed [2+2+2] Cycloaddition2.3 Totally Intramolecular [2+2+2] Cycloaddition Reactions3 Formation of Heterocycles3.1 Cycloaddition of Alkynes with Nitriles3.2 Cycloaddition of 1,6-Diynes with Cyanamides3.3 Cycloaddition of 1,6-Diynes with Selenocyanates3.4 Cycloaddition of Imines with Allenes or Alkenes3.5 Cycloaddition of (Thio)Cyanates and Isocyanates3.6 Cycloaddition of 1,3,5-Triazines with Allenes3.7 Cycloaddition of Aldehydes with Enynes or Allenes/Alkenes3.8 Totally Intramolecular [2+2+2] Cycloaddition Reactions4 Conclusion

Sign in / Sign up

Export Citation Format

Share Document