Teck-Peng Loh

Rhodium‐Catalyzed CH Alkynylation of Arenes at Room Temperature

The rhodium(III)-catalyzed ortho C-H alkynylation of non-electronically activated arenes is disclosed. This process features a straightforward and highly effective protocol for the synthesis of functionalized alkynes and represents the first example of merging a hypervalent iodine reagent with rhodium(III) catalysis. Notably, this reaction proceeds at room temperature, tolerates a variety of functional groups, and more importantly, exhibits high selectivity for monoalkynylation.

l-Proline in an ionic liquid as an efficient and reusable catalyst for direct asymmetric aldol reactions

Abstract l -proline in imidazolium-based ionic liquids has been successfully used as an efficient and reusable catalyst for direct asymmetric aldol reactions.

Palladium‐Catalyzed Direct Arylation of Cyclic Enamides with Aryl Silanes by sp2 CH Activation

It does get in! A fluoride-assisted direct cross-coupling of cyclic enamides with trialkoxy aryl silanes by a palladium-catalyzed C--H activation leads to a wide range of enamides in yields of up to 95 %.

Direct Cross-Coupling Reaction of Simple Alkenes with Acrylates Catalyzed by Palladium Catalyst

An efficient methodology for oxidative cross-coupling reaction of olefins with acrylates catalyzed by palladium(II) was developed. The corresponding dienoates were obtained in moderate to good yields.

Catalytic enantioselective diels-alder addition to furan provides a direct synthetic route to many chiral natural products

Abstract An oxazaborolidine derived from N-tosyl (αS,βR)-β-methyltryptophan (1)catalyzes the Diels-Alder reaction of 2-bromoacrolein and furan with 96:4 enantioselectivity, leading to an efficient synthesis of numerous chiral 7-oxabicyclo[2.2.1]heptene derivatives.

Directing‐Group‐Assisted Copper‐Catalyzed Olefinic Trifluoromethylation of Electron‐Deficient Alkenes

Assistance provided: The directing group in the title reaction not only activates the substrates but also allows the stereospecific formation of cis-trifluoromethylated products. The reaction is operationally simple and tolerates a wide variety of functional groups, thus providing an efficient method for the stereoselective synthesis of β-CF3 -functionalized acrylamide derivatives.

Three Component Synthesis of β-Amino Carbonyl Compounds Using Indium Trichloride-Catalyzed One-pot Mannich-type Reaction in Water

Abstract The use of indium trichloride as catalyst in a one-pot Mannich reaction in water gives high yields for the formation of β-aminoketones/esters/acids is described. The catalyst can be recycled when the reaction is complete (Loh T.-P.; Wei L.-L. Tetrahedron Lett. 1998, 39, 323).

Palladium-catalyzed oxime assisted intramolecular dioxygenation of alkenes with 1 atm of air as the sole oxidant.

This paper describes a palladium-catalyzed oxime assisted intramolecular dioxygenation of alkenes by using 1 atm of air as the sole oxidant under extremely mild conditions, which demonstrated the feasibility of incorporating atmospheric oxygen into synthetically useful products under 1 atm of air at room temperature.

Novel one-pot Mannich-type reaction in water: Indium trichloride-catalyzed condensation of aldehydes, amines and silyl enol ethers for the synthesis of β-amino ketones and esters

Abstract Novel one-pot Mannich-type reaction between aldehydes, amines and silyl enol ethers is catalyzed by indium trichloride in water to give β-amino ketones and esters in moderate to good yields.

Oxidant-Free Rh(III)-Catalyzed Direct C–H Olefination of Arenes with Allyl Acetates

Rh(III)-catalyzed direct olefination of arenes with allyl acetate via C-H bond activation is described using N,N-disubstituted aminocarbonyl as the directing group. The catalyst undergoes a redox neutral process, and high to excellent yields of trans-products are obtained. This protocol exhibits a wide spectrum of functionality compatibility because of the simple reaction conditions employed and provides a highly effective synthetic method in the realm of C-H olefination.