271256-70-3

Upstream product

• 4636-16-2 iodoacetophenone 
• 693-02-7 hex-1-yne 
• 2142-70-3 2-iodoacetophenone 
• 2142-69-0 2-bromophenyl methyl ketone 

Downstream Products

• 1202458-00-1 (E)-1-(2-(hex-1-yn-1-yl)phenyl)ethanone oxime 
• 613666-91-4 1-(2-(hex-1-yn-1-yl)phenyl)ethan-1-ol 
• 1241049-26-2 C₁₄H₁₇NO 
• 1416952-29-8 C₁₆H₂₃O₄P 
• 1213789-42-4 2-(2-hex-1-ynylphenyl)-2-methyloxirane 

Relevant academic research and scientific papers

A Mild and Regioselective Synthesis of α-Fluoroketones via Gold and Selectfluor Partnership

An efficient, mild and rapid synthesis of α-fluoroketones has been developed, via a fruitful association between gold and Selectfluor starting from aldehyde-yne and alkynylaryl ketone derivatives. Several functionalized and synthetically highly valuable α-fluoroketones (21 compounds, up to 92%) were isolated in good to excellent yields via a remarkable regioselective oxyfluorination reaction in EtOH/H2O at room temperature. We have shed some light on parts of the mechanism by reacting diphenylacetylene and aldehyde-yne with or without Selectfluor. The reaction most presumably occurs via a sequential gold-catalyzed regioselective hydration followed by the α-fluorination reaction, but the presence of aldehyde moiety is crucial for the reactivity of alkyne function. The fluoroketones were efficiently transformed to 4-fluoroisoquinolines (9 compounds, 82–95%) of high pharmaceutical interest. (Figure presented.).

Mechanistic Investigation of the Formation of Isoindole N-Oxides in the Electron Transfer-Mediated Oxidative Cyclization of 2′-Alkynylacetophenone Oximes

This paper describes a joint experiment-theory investigation of the formation and cyclization of 2′-alkynylacetophenone oxime radical cations using photoinduced electron transfer (PET) with DCA as the photosensitizer. Using a combination of experimental 1H and 13C nuclear magnetic resonance (NMR) spectra, high-resolution mass spectrometry, and calculated NMR chemical shifts, we identified the products to be isoindole N-oxides. The reaction was found to be stereoselective; only one of the two possible stereoisomers is formed under these conditions. A detailed computational investigation of the cyclization reaction mechanism suggests facile C-N bond formation in the radical cation leading to a 5-exo intermediate. Back-electron transfer from the DCA radical anion followed by barrierless intramolecular proton transfer leads to the final product. We argue that the final proton transfer step in the mechanism is responsible for the stereoselectivity observed in experiment. As a whole, this work provides new insights into the formation of complex heterocycles through oxime and oxime ether radical cation intermediates produced via PET. Moreover, it represents the first reported formation of isoindole N-oxides.

Borylative Heterocyclization without Air-Free Techniques

In contrast to previously reported borylative heterocyclization methods, a reaction here proceeds without air-free techniques to access synthetically useful borylated thiophenes, benzothiophenes, and isocoumarins. A comparison of stability/decomposition rates in air of several catecholboronic ester (Bcat) compounds derived from different heterocycle cores showed a strong dependence on the heterocycle structure. Lessons learned from this comparison were then harnessed for the development of borylative heterocyclization reactions under ambient-atmosphere conditions and with wet solvent. In contrast to literature reports suggesting general moisture sensitivity, a subset of Bcat products resulting from this technique were chromatography-stable and directly isolable, obviating the requirement for an extra synthetic transformation into more stable boron species, such as pinacolboronic esters (Bpin), for isolation. The isolated Bcat products were amenable to various downstream functionalization reactions, including reactions that were not accessible with their better-known Bpin counterparts, showing the complementarity of Bcat reaction partners and expanding their known chemistry. These results suggest the value of conceptual revisitation of substitution and solvent influence on stability and isolability of organo-Bcat compound classes and lay the groundwork for development of additional practical borylative methods in air.

Exploiting Hydrazones to Improve the Efficiency of 6π-Electrocyclization Reactions of 1-Azatrienes

The greater geometric lability of hydrazones compared to that of oxime ethers is used as a basis to overcome the reluctance of Z-oxime ether azatrienes to undergo electrocyclization toward the synthesis of borylated (heteroaromatic) pyridines and ring-fused analogues. Such hydrazones now allow access to previously inaccessible tri- and tetrasubstituted 3-borylpyridines in high yields.

Copper-Catalyzed Cascade Cyclization of Arylsulfonylhydrazones Derived from ortho-Alkynyl Arylketones: Regioselective Synthesis of Functionalized Cinnolines

A novel copper-catalyzed cascade reaction of arylsulfonylhydrazones derived from ortho-alkynyl arylketones was accomplished. This reaction provides concise access to diversified cinnolines in good yields. The mechanistic investigations have disclosed involvement of the key alkynyl amination, 1,4-aryl migration, desulfonylation, and diazo radical cyclization cascade in the transformation.

An Oxyboration Route to a Single Regioisomer of Borylated Dihydrofurans and Isochromenes

An oxyboration reaction that employs B-O σ bonds as addition partners to C-C π bonds to form borylated dihydrofurans and isochromenes has been developed. By nature of the mechanism, the reaction produces exclusively one borylated regioisomer, in contrast to and/or complementary to alternative routes that produce these borylated heterocycles via C-H activation. Access to the borylative heterocyclization route is demonstrated from alcohols directly or from a hydroboration-oxyboration sequence starting from the corresponding ketone, forming the heterocyclic core and installing the boron in one synthetic step. Catechol boronates were directly used as coupling partners in the in situ Suzuki cross-coupling reactions without transesterification to pinacol boronates.

Iodine-Mediated Cyclization of ortho-Alkynylaryl Ketones for the Synthesis of Indenone Derivatives

A new method for the synthesis of indenone derivatives based on the I2-promoted cyclization of ortho-alkynylaryl ketones has been developed. This method provides a metal-free and convenient route for the regioselective synthesis of indenones using ortho-alkynylaryl ketones with predefined substituents to give indenone products in moderate to good yields.

Asymmetric Hydrogenation of In Situ Generated Isochromenylium Intermediates by Copper/Ruthenium Tandem Catalysis

The first asymmetric hydrogenation of in situ generated isochromenylium derivatives is enabled by tandem catalysis with a binary system consisting of Cu(OTf)2 and a chiral cationic ruthenium–diamine complex. A range of chiral 1H-isochromenes were obtained in high yields with good to excellent enantioselectivity. These chiral 1H-isochromenes could be easily transformed into isochromanes, which represent an important structural motif in natural products and biologically active compounds. The chiral induction was rationalized by density functional theory calculations.

Catalytic Sulfur-Enabled Dehydrobicyclization of 1,6-Enynes toward Arylated Indeno[1,2-c]thiophenes

A new copper-catalyzed sulfur-enabled dehydrobicyclization of 1,6-enynes using potassium sulfide as a sulfurating reagent has been established, providing a straightforward access toward arylated indeno[1,2-c]thiophenes with moderate to good yields. This sulfur incorporation pathway involves Michael addition, 5-exo-dig/5-endo-trig bicyclization and dehydrogenation sequence, resulting in continuous multiple bond-forming events including C-S and C-C bonds to rapidly construct functional organic molecules.

Synthesis of Functionalized 1H-Isochromene Derivatives via a Au-Catalyzed Domino Cycloisomerization/Reduction Approach

A Au-catalyzed versatile and efficient access to 1H-isochromenes is reported. The efficiency of the [AuCl2(Pic)] complex (1-5 mol %) was demonstrated and allowed a domino cycloisomerization/reduction reaction process starting from a wide range of functionalized ortho-alkynylbenzaldehydes and one example of ortho-alkynylpyridinylaldehyde. The smooth reaction conditions were amenable to aryl- and alkyl-substituted alkynyl derivatives, as well as functionalized halogen and ether moieties, leading to a chemo- and regioselective 6-endo-cyclization with good to excellent yields.