18887-52-0

Upstream product

• 308324-07-4 C₃₆H₂₆O₄ 
• 38399-13-2 2,2'-dibromotolane 
• 68-12-2 N,N-dimethyl-formamide 
• 38846-64-9 2-ethynylbenzaldehyde 
• 6630-33-7 ortho-bromobenzaldehyde 

Downstream Products

• 18887-49-5 2-[2-(2-hydroxymethylphenyl)-1-ethynyl]phenylmethanol 
• 431879-81-1 C₁₆H₁₂Cl₂ 
• 1250981-19-1 1,1'-(ethyne-1,2-diyldi-2,1-phenylene)bis[4-(triisopropylsilyl)but-3-yn-1-ol] 
• 1268368-03-1 dimethyl 2,2'-(2,2'-(ethyne-1,2-diyl)bis(2,1-phenylene))bis(hydroxymethylene) 
• 1268368-23-5 C₂₀H₂₂O₂ 
• 1639883-21-8 C₂₀H₁₆N₂O₂ 
• 18887-53-1 2-<2-<2-(Hydroxymethyl)phenyl>ethynyl>benzaldehyde 
• 166757-13-7 2-(1H-2-Benzopyran-3-yl)benzaldehyde 

Relevant academic research and scientific papers

Straightforward Synthesis and Properties of Highly Fluorescent [5]- and [7]-Helical Dispiroindeno[2,1-c]fluorenes

This work presents a general approach for synthesis of substituted [5]-helical dispiroindeno[2,1-c]fluorenes based on Rh-catalyzed intramolecular cyclotrimerization of triynes. This approach was further extended for the first synthesis of configurationally stable [7]-helical dispiroindeno[2,1-c]fluorenes. A series of variously substituted derivatives was prepared and their photophysical and electrochemical properties were evaluated. Their fluorescence emission maxima were in the region of 351–428 nm and quantum yields up to 88 % are the highest measured among the full-carbon helical compounds.

Regio- and stereoselective intramolecular hydroalkoxylation of aromatic alkynols: an access to dihydroisobenzofurans under transition-metal-free conditions

An efficient, transition-metal-free method to synthesize dihydroisobenzofuran derivatives via intramolecular hydroalkoxylation of aromatic alkynols with the promotion of cesium carbonate has been developed. The reaction proceeds regioselectively with exclusive formation of 5-exo-dig product, and only Z-isomer of the new generated double bond is observed. This new protocol features with milder reaction conditions, more convenient operation and satisfactory selectivities.

Gold-Catalyzed Access to 1H-Isochromenes: Reaction Development and Mechanistic Insight

The gold-catalyzed domino cyclization/nucleophilic reaction of ortho-carbonylalkynylaryls has been studied. Thus, 2-(pyridin-2-ylethynyl)benzaldehyde has been chosen to isolate key intermediates that may take part in the reaction mechanism. Employing Hantzsch ester (HEH) as nucleophile, it has been impossible to isolate the corresponding gold-alkenyl specie; however, when methanol was used as solvent (and nucleophile), the expected chelate gold-vinyl complex was isolated and unambiguously characterized by X-ray analysis. When HEH is present in the alcoholic reaction mixture, isotopic studies show that the cleavage of the Au-C bond of gold-vinyl complex proceeds through a protodemetalation pathway, rather than a plausible metal-hydride reductive elimination mechanism. Finally, with the aim of broadening the scope of the cyclization/reduction reaction previously reported, we present that the catalytic system is robust and applicable for a diverse family of challenging substrates presenting ester, aldehyde, ether, alkene, and alkyne functionalities.

Gold(I)-catalyzed asymmetric desymmetrization of meso-alkynyl diols and kinetic resolution of the corresponding DL-diols: Effects of celite filtration and silver salts

The asymmetric desymmetrization of meso-2-alkynylbenzenediols through the use of a combination of axially chiral diphosphine(AuCl)2 precatalysts and silver salt co-catalysts gave optically active isochromene compounds with high enantioselectivities in good yields. The corresponding dl-diol isomers underwent efficient kinetic resolution to give the cyclized isochromenes and recovered diols with high enantioselectivities under similar conditions. The high reactivity and selectivity in the desymmetrization of the meso-diols is independent of the combination of axially chiral diphosphine(AuCl)2 precatalyst and silver salt co-catalyst, whereas the corresponding tricarbonylchromium complexes of alkynylbenzenediols were affected by the combination of the diphosphine(AuCl)2 and silver salt. The reactivity was largely dependent on the nature of the gold(I) species.

AgI-catalyzed cascade strategy: Regioselective access to diversely substituted fused benzimidazo[2,1-a]isoquinolines, naphthyridines, thienopyridines, and quinoxalines in water

An environmentally benign and operationally simple one-pot approach to the regioselective tandem synthesis of diversely substituted fused benzimidazo[2,1-a]isoquinolines, naphthyridines, thienopyridines, and quinoxalines from o-alkynylaldehydes and arylamines with tethered nucleophiles using AgI as catalyst in water is described. The reaction showed selective N-C bond formation on the more electrophilic alkynyl carbon, resulting in the regioselective 6-endo-dig cyclized products in good to excellent yields. The proposed mechanistic pathway for the synthesis of fused heterocycles proceeding through formation of ring A prior to ring B, which formed through a second intramolecular attack of the nitrogen onto the alkynyl carbon, was supported by mechanistic experiments and X-ray crystallographic studies of isolated intermediate U and cyclized product 5a. Comparative experiments showed the viability of intramolecular nucleophilic attack over intermolecular attack of an external nucleophile. This catalytic, green protocol has been efficiently applied for the bis-tandem cyclization in water. An eco-friendly, one-pot cascade approach to benzimidazoles and quinoxalines in water using AgNO 3 as catalyst from o-alkynyl aldehydes and amines with tethered nucleophiles, has been developed. Selective 6-endo-dig regioselectivity and structural diversity are accomplished in good yields with a range of substrates. X-ray crystallographic studies and mechanistic experiments are also presented. Copyright

Synthesis of biaryl compounds using tandem ruthenium-catalyzed ring-closing metathesis

Tandem ring-closing enyne metathesis (RCEM)/ring-closing olefin metathesis (RCM) of tetraenynes with Grubbs second-generation catalyst, followed by elimination, was found to be a new and efficient synthetic approach to biaryl compounds. A preliminary asymmetric version of this approach, which used homochiral Ru-alkylidene catalysts, is also presented. A ringing endorsement: Tandem ring-closing enyne metathesis (RCEM)/ring-closing olefin metathesis (RCM) of tetraenynes with the Grubbs second-generation catalyst followed by elimination, was found to be a new and efficient synthetic approach to biaryl compounds (see scheme). A preliminary asymmetric version of this approach is also presented.

Novel π-conjugated cyclophanes: Magazine rack molecules

Synthesis of cyclophanes having alternating arylene-ethynylene as well as-ethenylene arrays is described. It is disclosed that these compounds are chiral on the basis of X-ray analysis and fluxional in solution on the basis of NMR spectra.

Integrated chemical process. Convergent strategy for ortho-phenylene ethynylene skeleton by one-pot double elimination method

Convergent strategies for ortho-phenylene ethynylene skeletons are realized on the basis of one-pot double elimination method. This protocol overcomes unavoidable difficulties encountered in Sonogashira coupling.