So Won Youn

The recent advent of transition-metal mediated C-H activation is revolutionizing the synthetic field and gradually infusing a "C-H activation mind-set" in both students and practitioners of organic synthesis. As a powerful testament of this emerging synthetic tool, applications of C-H activation in the context of total synthesis of complex natural products are beginning to blossom. Herein, recently completed total syntheses showcasing creative and ingenious incorporation of C-H activation as a s

A Pd-catalyzed oxidative C-H amination of N-Ts-2-arylanilines under ambient temperature using Oxone as an inexpensive, safe, and easy-to-handle oxidant has been developed. This process represents a green and practical method for the facile construction of carbazoles with a broad substrate scope and wide functional group tolerance.

We herein report that RuCl3/AgOTf has proven to be a hydroarylation catalyst with an efficiency and scope superior to previously known methods. This catalyst demonstrated consistent performance with arene-ene substrates of diverse structural features, providing good to excellent yields of cyclization products (chromanes, tetralins, terpenoids, dihydrocoumarins).

Mild and efficient AuCl3/AgOTf-catalyzed Pictet-Spengler reactions were developed to afford in good yields a variety of tetrahydroisoquinoline and tetrahydro-beta-carboline ring systems, which constitute important motifs in biologically active natural and synthetic organic compounds.

Abstract Tandem transformations represent one of the most efficient methods for the synthesis of complex molecules from readily available starting materials, as evidenced by the intense research activity and the plethora of literature published in this area. This review highlights recent developments of rhodium(I)‐catalyzed tandem transformations with organoboron compounds involving the formation of multiple carbon–carbon bonds. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2

A Pd(II)-catalyzed reaction engaging alkenyl β-keto esters is reported that leads to the formation of 1-naphthols and an unexpected generation of arylpalladium(II) species. Interception of the in situ generated arylpalladium(II) species in a Mizoroki–Heck reaction, together with additional mechanistic studies, provided strong evidence in support of the first aromatization-driven β-carbon elimination process. A single Pd catalyst served to promote a series of both C–C bond forming and cleavage ev

Mild, efficient, and economical Ag(I)-catalyzed sequential C-C/C-O bond formations between phenols and dienes were developed to afford in good yields a variety of dihydrobenzopyran and dihydrobenzofuran ring systems, which are important motifs in both naturally occurring and biologically active compounds.

[reaction: see text]. We herein report the development of one-pot procedures for the conversion of allyl aryl ethers to 2-methylbenzofurans (via sequential Claisen rearrangement and oxidative cyclization) and for the conversion of aryl homoallyl ethers to chromenes (via direct oxidative cyclization). It is likely that both reactions proceed via a common Pd-catalyzed pathway involving olefin activation, nucleophilic attack, and beta-hydride elimination.

(2006). THE PICTET-SPENGLER REACTION: EFFICIENT CARBON-CARBON BOND FORMING REACTION IN HETEROCYCLIC SYNTHESIS. Organic Preparations and Procedures International: Vol. 38, No. 6, pp. 505-591.

Abstract Indoles are important structural motifs that are commonly found in a diverse array of natural products, pharmaceuticals, and other functional molecules. Consequently, the development of new, more efficient synthetic methods for the construction of substituted indoles continues to be of great importance and considerable interest. Over the past few decades, metal‐catalyzed C−C/C−N bond‐forming reactions have emerged as a powerful synthetic strategy for heterocyclic synthesis. In this revi

It is demonstrated that two organocatalysts, achiral NHC and chiral bifunctional cinchonine, are mutually compatible and operating concurrently and effectively to promote the asymmetric domino oxidation/oxa-Michael addition reaction. This protocol allowed access to both enantiomers of a product by using two natural, inexpensive pseudoenantiomeric cinchona alkaloids, cinchonine and cinchonidine, as well as to phthalides containing a chiral quaternary carbon center in good enantioselectivities.

A new Rh(I)-catalyzed tandem conjugate addition-Mannich cyclization reaction of imine-substituted electron-deficient alkenes with arylboronic acids has been developed to afford 2,3,4-trisubstituted 1,2,3,4-tetrahydroquinolines. This is the first example involving imine group as a secondary electrophile in Rh(I)-catalyzed tandem reactions.

Abstract A highly effective silver(I)‐mediated CH amination of 2‐alkenylanilines has been developed to afford a diverse range of substituted indoles. High functional group tolerance, broad substrate scope, simple/fast/high‐yielding reaction, and recovery/reuse of the inexpensive silver oxidant are noteworthy. Furthermore, an uncommon migratory process of β‐monosubstituted 2‐alkenylanilines with solvent‐dependence was demonstrated. magnified image

Abstract A cooperative indium(III)/silver(I) system for the synthesis of various five‐membered heterocycles, including dihydrofurans, pyrroles, spirolactones, and spiroiminolactones, through the sequential oxidative coupling/annulation reaction of 1,3‐dicarbonyl compounds with styrenes has been developed. Four different heterocyclic systems were successfully synthesized depending on the substitution pattern of the substrates using readily available starting materials. This system has the advanta