52188-06-4

Upstream product

• 624-31-7 4-tolyl iodide 
• 143952-57-2 ethyl (tributylstannyl)propiolate 
• 40886-61-1 (α-ethoxycarbonyl-α-4-methylbenzoylmethylene)triphenylphosphorane 
• 101458-36-0 2,3-dibromo-3-p-tolyl-propionic acid ethyl ester 
• 766-97-2 4-n-methylphenylacetylene 
• 2227-58-9 3-(4-methylphenyl)prop-2-ynoic acid 
• 75-03-6 ethyl iodide 
• 104-87-0 4-methyl-benzaldehyde 
• 60512-56-3 1-(2,2-dibromovinyl)-4-methylbenzene 
• 541-41-3 chloroformic acid ethyl ester 
• 4294-57-9 para-methylphenylmagnesium bromide 
• 41658-03-1 ethyl 3-bromoprop-2-ynoate 
• 623-47-2 propynoic acid ethyl ester 
• 617-37-8 oxalic acid monoethyl ester 

Downstream Products

• 77930-34-8 7,10-Diethyl-9-p-tolyl-fluoranthene-8-carboxylic acid ethyl ester 
• 77930-35-9 7,10-Dipropyl-9-p-tolyl-fluoranthene-8-carboxylic acid ethyl ester 
• 77930-36-0 7,10-Dibutyl-9-p-tolyl-fluoranthene-8-carboxylic acid ethyl ester 
• 2227-58-9 3-(4-methylphenyl)prop-2-ynoic acid 
• 24785-38-4 1-methoxy-4-[2-(4-methylphenyl)ethynyl]benzene 
• 1350934-78-9 ethyl 2-(p-tolyl)quinoline-3-carboxylate 
• 1638667-54-5 (Z)-ethyl 3-chloro-2-((4-oxooxetan-2-yl)methyl)-3-(p-tolyl)acrylate 
• 102755-14-6 ethyl-10-(p-tolyl)-phenanthrene-9-carboxylate 

Relevant academic research and scientific papers

Br?nsted Acid Catalyzed Friedel–Crafts-Type Coupling and Dedinitrogenation Reactions of Vinyldiazo Compounds

The direct Friedel–Crafts-type coupling and dedinitrogenation reactions of vinyldiazo compounds with aromatic compounds using a metal-free strategy are described. This Br?nsted acid catalyzed method is efficient for the formation of α-diazo β-carbocations (vinyldiazonium ions), vinyl carbocations, and allylic or homoallylic carbocation species via vinyldiazo compounds. By choosing suitable nucleophilic reagents to selectively capture these intermediates, both trisubstituted α,β-unsaturated esters, β-indole-substituted diazo esters, and dienes are obtained with good to high yields and selectivity. Experimental insights implicate a reaction mechanism involving the selective protonation of vinyldiazo compounds and the subsequent release of dinitrogen to form vinyl cations that undergo intramolecular 1,3- and 1,4- hydride transfer processes as well as fragmentation.

Environment-friendly preparation method of ozagrel impurity II

The invention provides an environment-friendly preparation method of an ozagrel impurity II, and belongs to the technical field of preparation of drug impurity standard substances. The preparation method comprises the following steps: reacting 4-iodotolue

Gold-catalyzed partial hydrogenation of activated alkynes mediated by triphenylphosphine

Gold(I) can exhibit a cooperative effect with triphenylphosphine, accelerating the triphenylphosphine-mediated partial hydrogenation of activated alkynes. In this protocol, 3-arylpropiolates are selectively reduced to the Z -isomer when the aryl ring bears an electron-donor substituent, whereas 3-arylpropynones are reduced to the E-isomers.

Consecutive Three-Component Coupling-Addition Synthesis of β-Amino Enoates and 3-Hydroxypyrazoles via Ethyl 3-Arylpropiolates

Two consecutive three-component syntheses furnishing β-amino enoates or 3-hydroxypyrazoles based upon the Sonogashira alkynylation of aryl iodides and ethyl propiolate were established in mostly excellent yields. The ethyl 3-arylpropiolate intermediates are Michael systems which are suited for concatenation with conjugate addition or cyclocondensation giving access to libraries of 21 different β-amino enoates and 17 different 3-hydroxypyrazoles. The rotational barrier of β-pyrrolidino enoates was assessed by studying the coalescence of pyrrolidinyl protons in VT-NMR spectra of electronically different substituted derivatives showing that the electronic substituent effect on the aryl group does not affect the height of the rotational barrier. This indicates that the substituents are essentially oriented orthogonally to the plane of the β-pyrrolidino enoates.

Metal-Free Oxidative [5+1] Cyclization of 1,5-Enynes for the Synthesis of Pyrazine 1-Oxide

A chemo-selective nitrosylation of 1,5-enynes via a sequence of NO radical incorporation and intramolecular radical cyclization was reported. The formation of two C?N bonds and one C?O bond make this [5+1] cycloaddition reaction an efficient approach to synthesize pyrazine 1-oxides in moderate to good yields. Metal-free, short reaction time and mild conditions render this strategy more practical, eco-friendly and convenient. Synthetic utility of this protocol is highlighted by scaffolds diversification. (Figure presented.).

Selective synthesis of trisubstituted pyrroles through the reactions of alkynyl Fischer carbene complexes with oxazolones

An efficient and simple synthesis of novel trisubstituted 1H-pyrroles 4a-qvia 1,3-dipolar cycloaddition of Δ3-trifluoromethyloxazolones 2a-d with both chromium and tungsten alkynyl Fischer carbene complexes (1a-h) is described. An unexpected and unreported -CF3 group elimination process was observed in the pyrrole structure. Our experimental and theoretical data suggested that the metal fragment may be responsible for this phenomenon. The dipolar cycloaddition proceeded efficiently to produce a single regioisomer, which was unambiguously established through NMR and single-crystal X-ray diffraction studies. Nevertheless, the reaction of alkynyl carbenes bearing an α,β,γ,δ-unsaturated moiety with excess oxazolone 2a produced a polycyclic compound 6 speculatively formed through a cascade reaction involving 1,6-, 1,4- and 1,2-nucleophilic addition steps.

Water as a Hydrogenating Agent: Stereodivergent Pd-Catalyzed Semihydrogenation of Alkynes

Palladium-catalyzed transfer semihydrogenation of alkynes using H2O as the hydrogen source and Mn as the reducing reagent is developed, affording cis- and trans-alkenes selectively under mild conditions. In addition, this method provides an efficient way to access various cis-1,2-dideuterioalkenes and trans-1,2-dideuterioalkenes by using D2O instead of H2O.

Palladium-Catalyzed Regio- and Stereoselective Sulfonylation of Aryl Propiolates with Sulfonyl Hydrazides: Access to (E)-β-Aryl Sulfonyl Acrylates

An efficient method for the synthesis of (E)-β-aryl sulfonyl acrylates has been reported. This palladium-catalyzed approach showed excellent regio- and stereoselectivity in the sulfonylation of aryl propiolates with sulfonyl hydrazides. Through this approach, a wide range of (E)-β-aryl sulfonyl acrylates were obtained in moderate to high yields. (Figure presented.).

A Parallel Approach to 7-(Hetero)arylpyrazolo[1,5- a]pyrimidin-5-ones

A modular, two-pot assembly of 7-arylpyrazolo[1,5-a]pyrimidones from aryl/heteroaryl halides and aminopyrazoles in library format was developed. Sonogashira coupling of aryl bromides with triethyl orthopropiolate, followed by in situ orthoester hydrolysis

3-Phenothiazinyl propiolates – Fluorescent electrophores by Sonogashira coupling of ethyl propiolate

Fluorescent ethyl 3-phenothiazinyl propiolates with reversible Nernstian oxidation potentials were efficiently synthesized by an improved Sonogashira coupling of aryl iodides and ethyl propiolate. The versatility of this modified alkynylation was illustrated by 13 ethyl 3-arylpropiolates in mostly excellent yields with a broad substrate scope. In addition to reversible one-electron oxidations, the title compounds reveal large Stokes shifts, high fluorescence quantum yields, and solvatochromic emission. The photophysical characteristics were corroborated and rationalized by DFT and TD-DFT calculations.