282103-88-2

Upstream product

• 59046-72-9 o-(phenylethynyl)benzaldehyde 
• 1119-51-3 bromopentene 
• 536-74-3 phenylacetylene 
• 34164-50-6 4-penten-1-ylmagnesium bromide 
• 6630-33-7 ortho-bromobenzaldehyde 

Downstream Products

• 282103-89-3 1-(2-(phenylethynyl)phenyl)hex-5-en-1-one 

Relevant academic research and scientific papers

Silver-catalyzed C-C bond formation with carbon dioxide: Significant synthesis of dihydroisobenzofurans

The silver salt catalyzed the C-C bond forming reaction of o-alkynylacetophenone derivatives and carbon dioxide. In this reaction, a carbonyl group and a furan skeleton were successively constructed to afford the corresponding dihydroisobenzofuran derivatives.

AuBr3- and Cu(OTf)2-catalyzed intramolecular [4 + 2] cycloaddition of tethered alkynyl and alkenyl enynones and enynals: A new synthetic method for functionalized polycyclic hydrocarbons

(Chemical Equation Presented) Treatment of tethered alkynyl enynones 8, in which a carbon chain is attached to the carbonyl group, with a catalytic amount of AuBr3in (ClCH2)2 gave the naphthyl ketones 9 in good to high yields (top-down approach). Analogously, the AuBr 3-catalyzed benzannulations of 10, in which a carbon tether is extended from the alkynyl terminus, also proceeded smoothly, and the cyclized naphthyl ketones 11 were obtained in high yields (bottom-up approach). Similarly, when two kinds of tethered alkenyl enynones 12 and 14 were treated with Cu(OTf)2 catalyst, the corresponding dihydronaphthyl ketone products 13 and 15 were obtained in high yields, respectively. The present formal [4 + 2] intramolecular cycloaddition proceeds most probably through the coordination of the triple bond at the ortho position of substrates to Lewis acids, the formation of benzopyrylium ate complex 16 via the nucleophilic addition of the carbonyl oxygen atom, the reverse electron demand type Diels-Alder addition of the tethered alkynes or alkenes to the ate complex, and subsequent bond rearrangement.

Rhodium(II)-catalyzed carbocyclization reaction of α-diazo carbonyls with tethered unsaturation

o-Alkynyl-substituted α-diazoketones undergo internal cyclization to produce indenone derivatives upon treatment with catalytic quantities of Rh(II)-carboxylates. A variety of structural influences were encountered by varying the nature of the substituent group attached to the diazo center. The cyclization reaction involves addition of a rhodium-stabilized carbenoid onto the acetylenic π-bond to generate a cycloalkenone carbenoid. The cyclized carbenoid was found to undergo both aromatic and aliphatic C-H insertion as well as cyclopropanation across a tethered π-bond. Subjection of diazo phenyl acetic acid 3-phenylprop-2-ynyl ester to Rh(II) catalysis furnished 8- phenyl-1,8-dihydro2-oxacyclopenta[a]indenone in high yield. The formation of this compound involves cyclization of the initially formed carbenoid onto the alkyne to produce a butenolide which then undergoes C-H insertion into the neighboring aromatic system. When a vinyl ether is added, the initially formed rhodium carbenoid intermediate can be intercepted by the electron-rich π-bond prior to cyclization. Different rhodium catalysts were shown to result in significant variation in the product ratios. The competition between bimolecular cyclopropanation, 1,2-hydrogen migration, and internal cyclization was probed using several enol ethers as well as diazoesters which possess different substituent groups on the ester backbone. The specific path followed was found to depend on electronic, steric, and conformational factors.