Synthesis of γ-Carbolines through Annulative Cyclization between Indolyl Azines and Alkynes under Rhodium Catalysis
Seungeun Lee1, Hoyoung Lee1, Anand Kumar1
1School of Pharmacy, Sungkyunkwan University, Suwon 16419, Republic of Korea.
None:
Functionalized carbolines play a crucial role in the discovery of bioactive compounds and functional materials. In this study, we report a Rh(III)-catalyzed annulative synthesis of γ-carbolines from indolyl azines and internal alkynes. Remarkably, indolyl azines can undergo N-N bond cleavage under the influence of a Rh(III) catalyst, yielding 2-fold ketimines, which demonstrates the atom economy of indolyl azines in catalytic C-H functionalizations. A series of post-transformations for the synthesized products are also described.
More Related Videos
12:27Synthesis of Hypervalent Iodonium Alkynyl Triflates for the Application of Generating Cyanocarbenes
Published on: September 8, 2013
10:42Preparation of N-2-alkoxyvinylsulfonamides from N-tosyl-1,2,3-triazoles and Subsequent Conversion to Substituted Phthalans and Phenethylamines
Published on: January 3, 2018
Related Concept Videos
Cyclohexenones via Michael Addition and Aldol Condensation: The Robinson Annulation
Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
Preparation of 1° Amines: Azide Synthesis
Azide ions act as good nucleophiles and react with unhindered alkyl halides to form alkyl azides. Alkyl azides do not participate in further nucleophilic substitution reactions, thereby eliminating the chances of polyalkylated products. Alkyl azides are reduced by hydride-based reducing agents, like lithium aluminum...
Preparation of Alkynes: Dehydrohalogenation
Alkynes can be prepared by dehydrohalogenation of vicinal or geminal dihalides in the presence of a strong base like sodium amide in liquid ammonia. The reaction proceeds with the loss of two equivalents of hydrogen halide (HX) via two successive E2 elimination reactions.
Electrophilic Addition to Alkynes: Halogenation
Halogenation is another class of electrophilic addition reactions where a halogen molecule gets added across a π bond. In alkynes, the presence of two π bonds allows for the addition of two equivalents of halogens (bromine or chlorine). The addition of the first halogen molecule forms a trans-dihaloalkene as the major product and the cis isomer as the minor product. Subsequent addition of the second equivalent yields the tetrahalide.
Cycloaddition Reactions: Overview
