36888-18-3

Usage

Synthesis Reference(s)

Tetrahedron Letters, 23, p. 2277, 1982 DOI: 10.1016/S0040-4039(00)87320-7

Upstream product

• 698-20-4 1-(diazomethyl)-2-methylbenzene 
• 933-88-0 ortho-toluoyl chloride 
• 158871-10-4 2-methylbenzyl(diphenyl)phosphine oxide 
• 529-20-4 2-methylphenyl aldehyde 
• 62778-16-9 diethyl 2-methylbenzylphosphonate 
• 400848-56-8 C₉H₈Cl₂O₂ 
• 159386-40-0 1-[Chloro-(diphenyl-phosphinoyl)-methyl]-2-methyl-benzene 
• 932-31-0 ortho-tolylmagnesium bromide 
• 5294-03-1 di-o-tolylethyne 
• 110-82-7 cyclohexane 
• 35629-84-6 N'-(2-methylbenzylidene)-4-methylbenzenesulfonohydrazide 
• 1486-28-8 diphenyl(methyl)phosphine 
• 552-45-4 1-chloromethyl-2-methylbenzene 
• 1377975-19-3 2-methylbenzylmethyldiphenylphosphonium chloride 

Downstream Products

• 22817-25-0 1,2-Di-o-tolyl-3,3-dichlor-cyclopropan 
• 7372-87-4 1,8-dimethylphenanthrene 
• 10311-74-7 cis-2,2'-dimethylstilbene 
• 172585-06-7 (S,S)-(+)-1,2-bis(2-methylphenyl)ethane-1,2-diol 
• 807630-81-5 (+)-trans-2,3-di(o-tolyl)oxirane: 
• 807630-81-5 (-)-trans-2,3-di(o-tolyl)oxirane: 
• 1006055-80-6 (1Z,3Z)-1,4-di(2-tolyl)-1,3-butadiene 
• 57542-70-8 α,α'-dibromo-2,2'-dimethyl-bibenzyl 
• 952-80-7 1,2-bis(2-methylphenyl)ethane 
• 64158-25-4 meso-1,2-bis(2-methylphenyl)ethane-1,2-diol 
• 34737-70-7 threo-1,2-bis(2-methylphenyl)ethane-1,2-diol 
• 529-20-4 2-methylphenyl aldehyde 

Relevant academic research and scientific papers

Energy-Transfer-Mediated Photocatalysis by a Bioinspired Organic Perylenephotosensitizer HiBRCP

Energy transfer plays a special role in photocatalysis by utilizing the potential energy of the excited state through indirect excitation, in which a photosensitizer determines the thermodynamic feasibility of the reaction. Bioinspired by the energy-transfer ability of natural product cercosporin, here we developed a green and highly efficient organic photosensitizer HiBRCP (hexaisobutyryl reduced cercosporin) through structural modification of cercosporin. After structural manipulation, its triplet energy was greatly improved, and then, it could markedly promote the efficient geometrical isomerization of alkenes from the E-isomer to the Z-isomer. Moreover, it was also effective for energy-transfer-mediated organometallic catalysis, which allowed realization of the cross-coupling of aryl bromides and carboxylic acids through efficient energy transfer from HiBRCP to nickel complexes. Thus, the study on the relationship between structural manipulation and their photophysical properties provided guidance for further modification of cercosporin, which could be applied to more meaningful and challenging energy-transfer reactions.

An Amine-Assisted Ionic Monohydride Mechanism Enables Selective Alkyne cis-Semihydrogenation with Ethanol: From Elementary Steps to Catalysis

The selective synthesis of Z-alkenes in alkyne semihydrogenation relies on the reactivity difference of the catalysts toward the starting materials and the products. Here we report Z-selective semihydrogenation of alkynes with ethanol via a coordination-induced ionic monohydride mechanism. The EtOH-coordination-driven Cl- dissociation in a pincer Ir(III) hydridochloride complex (NCP)IrHCl (1) forms a cationic monohydride, [(NCP)IrH(EtOH)]+Cl-, that reacts selectively with alkynes over the corresponding Z-alkenes, thereby overcoming competing thermodynamically dominant alkene Z-E isomerization and overreduction. The challenge for establishing a catalytic cycle, however, lies in the alcoholysis step; the reaction of the alkyne insertion product (NCP)IrCl(vinyl) with EtOH does occur, but very slowly. Surprisingly, the alcoholysis does not proceed via direct protonolysis of the Ir-C(vinyl) bond. Instead, mechanistic data are consistent with an anion-involved alcoholysis pathway involving ionization of (NCP)IrCl(vinyl) via EtOH-for-Cl substitution and reversible protonation of Cl- ion with an Ir(III)-bound EtOH, followed by β-H elimination of the ethoxy ligand and C(vinyl)-H reductive elimination. The use of an amine is key to the monohydride mechanism by promoting the alcoholysis. The 1-amine-EtOH catalytic system exhibits an unprecedented level of substrate scope, generality, and compatibility, as demonstrated by Z-selective reduction of all alkyne classes, including challenging enynes and complex polyfunctionalized molecules. Comparison with a cationic monohydride complex bearing a noncoordinating BArF- ion elucidates the beneficial role of the Cl- ion in controlling the stereoselectivity, and comparison between 1-amine-EtOH and 1-NaOtBu-EtOH underscores the fact that this base variable, albeit in catalytic amounts, leads to different mechanisms and consequently different stereoselectivity.

E, Z -Selectivity in the reductive cross-coupling of two benzaldehydes to stilbenes under substrate control

Unsymmetrical E- and Z-stilbenes can be synthesized from two differently substituted benzaldehydes in a MesP(TMS)Li-promoted reductive coupling sequence. Depending on the order of addition of the two coupling partners, the same olefin can be produced in either E- or Z-enriched form under identical reaction conditions. A systematic study of the correlation between the stereochemical outcome of the reaction and the substitution pattern at the two aldehydes is presented. The results can be used as guidelines to predict the product stereochemistry. This journal is

Acetylene as a Dicarbene Equivalent for Gold(I) Catalysis: Total Synthesis of Waitziacuminone in One Step

The gold(I)-catalyzed reaction of acetylene gas with alkenes leads to (Z,Z)-1,4-disubstituted 1,3-butadienes and biscyclopropanes depending on the donor ligand on gold(I). Acetylene was generated in situ from calcium carbide and water in a user-friendly p

Selenenate Anions (PhSeO?) as Organocatalyst: Synthesis of trans-Stilbenes and a PPV Derivative

The selenenate anion (RSeO?) is introduced as an active organocatalyst for the dehydrohalogen coupling of benzyl halides to form trans-stilbenes. It is shown that RSeO? is a more reactive catalyst than the previously reported sulfur analogues (sulfenate anion, RSO?) and selenolate anions (RSe?) in the aforementioned reaction. This catalytic system was also applied to the benzylic-chloromethyl-coupling polymerization (BCCP) of a bis-chloromethyl arene to form ppv (poly(p-phenylene vinylene))-type polymers with high yields, Mn (average molecular weight) up to 13,000 and ? (dispersity) of 1.15. (Figure presented.).

Using alcohols as simple H2-equivalents for copper-catalysed transfer semihydrogenations of alkynes

Copper(i)/N-heterocyclic carbene complexes enable a transfer semihydrogenation of alkynes employing simple and readily available alcohols such as isopropanol. The practical overall protocol circumvents the use of commonly employed high pressure equipment when using dihydrogen (H2) on the one hand, and avoids the generation of stoichiometric silicon-based waste on the other hand, when hydrosilanes are used as terminal reductants.

Photoinitiated carbonyl-metathesis: Deoxygenative reductive olefination of aromatic aldehydes: Via photoredox catalysis

Carbonyl-carbonyl olefination, known as McMurry reaction, represents a powerful strategy for the construction of olefins. However, catalytic variants that directly couple two carbonyl groups in a single reaction are less explored. Here, we report a photoredox-catalysis that uses B2pin2 as terminal reductant and oxygen trap allowing for deoxygenative olefination of aromatic aldehydes under mild conditions. This strategy provides access to a diverse range of symmetrical and unsymmetrical alkenes with moderate to high yield (up to 83%) and functional-group tolerance. To follow the reaction pathway, a series of experiments were conducted including radical inhibition, deuterium labelling, fluorescence quenching and cyclic voltammetry. Furthermore, NMR studies and DFT calculations were combined to detect and analyze three active intermediates: a cyclic three-membered anionic species, an α-oxyboryl carbanion and a 1,1-benzyldiboronate ester. Based on these results, we propose a mechanism for the CC bond generation involving a sequential radical borylation, "bora-Brook" rearrangement, B2pin2-mediated deoxygenation and a boron-Wittig process.

Selenolate Anion as an Organocatalyst: Reactions and Mechanistic Studies

A new organocatalyst, the selenolate anion [RSe]–, generated from bench-stable and commercially available diphenyl diselenide or from phenyl benzyl selenide (10 mol%) is introduced. Benchmarking is performed in the conversion of benzylic chlorides into trans-stilbenes selectively at room temperature. Mechanistic studies support the intermediacy of the selenolate anion and of 1,2-diphenylethyl phenyl selenide. (Figure presented.).

Ethylaluminum as an ethylene source for the Mizoroki-Heck-type reaction. Rhodium-catalyzed preparation of stilbene derivatives

Treatment of an organoaluminum reagent bearing aryl and ethyl groups furnishes 1,2-diarylethene derivatives in good to excellent yields by the catalysis of a rhodium complex, in which the ethyl group of the aluminum reagent serves as an ethylene source in the product formation.

A new role for sulfenate anions: Organocatalysis

(Chemical Equation Presented) The sulfenate anion is introduced for the first time as a catalyst and was found to facilitate the conversion of benzyl halides to trans-stilbenes. CPME=Cyclopentyl methyl ether.