52915-52-3

Upstream product

• 120-72-9 indole 
• 1179348-58-3 methyl 2-(dimethyl(oxo)-λ⁶-sulfaneylidene)-2-phenylacetate 
• 101-41-7 benzeneacetic acid methyl ester 
• 22979-35-7 Methyl phenyldiazoacetate 
• 17983-42-5 trimethylsilyl indole 

Relevant academic research and scientific papers

Metal-Free Directed Diastereoselective C2,C3-Cyclopropanation of Substituted Indoles with Diazoesters

A metal-free directed C2,C3-cyclopropanation of suitably substituted indoles with α-diazo esters has been accomplished for the diastereoselective synthesis of cyclopropane-fused indolines in good yield. This method works well with a wide range of differen

Enantioselective Indole Insertion Reactions of α-Carbonyl Sulfoxonium Ylides

The first example of organocatalytic enantioselective C–H insertion reactions of indoles and sulfoxonium ylides is reported. Under the influence of phosphoric acid catalysis, levels of enantiocontrol in the range of 20–93% ee and moderate yields (up to 50

Well-Defined, Versatile and Recyclable Half-Sandwich Nickelacarborane Catalyst for Selective Carbene-Transfer Reactions

Catalytic carbene-transfer reactions constitute a class of highly useful transformations in organic synthesis. Although catalysts based on a range of transition-metals have been reported, the readily accessible nickel(II)-based complexes have been rarely used. Herein, an air-stable nickel(II)-carborane complex is reported as a well-defined, versatile and recyclable catalyst for selective carbene transfer reactions with low catalyst loading under mild conditions. This catalyst is effective for several types of reactions including diastereoselective cyclopropanation, epoxidation, selective X?H insertions (X = C, N, O, S, Si), particularly for the unprotected substrates. This represents a rare example of carborane ligands in base metal catalysis.

Borane-Catalyzed Stereoselective C–H Insertion, Cyclopropanation, and Ring-Opening Reactions

Lewis acidic boranes have been shown to be effective metal-free catalysts for highly selective reactions of donor-acceptor diazo compounds to a range of substrates. The reactions of α-aryl α-diazoesters with nitrogen heterocycles indole or pyrrole selectively generate C3 and C2 C–H insertion products, respectively, in good to excellent yields even when using unprotected indoles. Alternatively, benzofuran, indene, and alkene substrates give exclusively cyclopropanated products with α-aryl α-diazoesters, whereas the reactions with furans lead to ring-opening. Comprehensive theoretical calculations have been used to explain the differing reactivities and high selectivities of these reactions. Overall, this work demonstrates the selective metal-free catalytic reactions of α-aryl α-diazoesters with (hetero)cycles and alkenes. This simple, mild reaction protocol represents an alternative to the commonly used precious metal systems and may provide future applications in the generation of biologically active compounds. Efficient and facile routes to heterocyclic compounds are highly desirable because of their remarkable biological importance and applications in drugs approved by the Food and Drug Administration. Current synthetic routes frequently use precious metal-catalyzed reactions. The problems associated with the limited resources of precious metals as well as their toxicities can be avoided through metal-free approaches. Our investigations on the reactivities of diazoesters toward the (hetero)arenes reveal that by using Lewis acidic triarylboranes as a catalyst, we can selectively effect C–H insertion, cyclopropanation, or ring-opening in good to excellent yields. Main group, or metal-free, catalysis has become a burgeoning field; yet, this flourishing field is still in its nascent stage. The work described herein represents a step toward improving the applicability of main group catalysis by employing metal-free approaches in the functionalization of organic compounds. This work demonstrates the highly selective metal-free catalytic reactions of α-aryl α-diazoesters with a range of (hetero)cycles and olefins using Lewis acidic boranes. The simple, mild reaction protocol employed represents an alternative to the commonly used precious metal systems and may provide future applications in the generation of biologically active compounds.

Enantioselective Palladium-Catalyzed Carbene Insertion into the N?H Bonds of Aromatic Heterocycles

C3-substituted indoles and carbazoles react with α-aryl-α-diazoesters under palladium catalysis to form α-(N-indolyl)-α-arylesters and α-(N-carbazolyl)-α-arylesters. The products result from insertion of a palladium-carbene ligand into the N?H bond of the aromatic N-heterocycles. Enantioselection was achieved using a chiral bis(oxazoline) ligand, in many cases with high enantioselectivity (up to 99 % ee). The method was applied to synthesize the core of a bioactive carbazole derivative in a concise manner.

Chemoselective carbophilic addition of α-diazoesters through ligand-controlled gold catalysis

The chemoselective addition of arenes and 1,3-diketones to α-aryldiazoesters was achieved through ligand-controlled gold catalysis. Unlike a dirhodium catalyst (which promotes C sp 3-H insertion and cyclopropanation) and a copper catalyst (which catalyzes O-H and N-H insertions), the gold catalyst with an electron-deficient phosphite as the ancillary ligand exclusively gave the carbophilic addition product, thus representing a new and efficient approach to form carbophilic carbocations , which selectively react with carbon nucleophiles.

CuO/SiO2 as a simple, effective and recoverable catalyst for alkylation of indole derivatives with diazo compounds

The purely inorganic copper oxide on silica catalyzes the reaction of methyl phenyldiazoacetate with N-methyl indole under mild reaction conditions, giving the alkylation (formally a C-H insertion) in position 3, and the catalyst can be recovered and reused at least in 5 consecutive runs with only minor loss in activity. The scope of the reaction includes various diazo compounds and indole or pyrrole derivatives leading to alkylation or cyclopropanation depending on the heterocycle structure. An alternative mechanism, without reduction of Cu(ii) to Cu(i), is proposed on the basis of the obtained results. The Royal Society of Chemistry 2013.