848312-59-4

Upstream product

• 848312-56-1 (E)-1-phenyl-8-(trimethylsilyl)oct-1-en-7-yn-3-ol 
• 14371-10-9 (E)-3-phenylpropenal 
• 35761-91-2 5-iodo-1-trimethylsilyl-1-pentyne 
• 94012-71-2 trimethyl(6-iodo-1-hexynyl)silane 

Downstream Products

• 848312-82-3 (1E)-1-phenyloct-1-en-7-yn-3-one 

Relevant academic research and scientific papers

Tungsten(0)- and rhenium(I)-catalyzed tandem cyclization of acetylenic dienol silyl ethers based on geminal carbo-functionalization of alkynes

Tungsten(0)- and rhenium(I)-catalyzed reactions of acetylenic dienol silyl ethers based on the concept of geminal carbo-functionalization of alkynes are reported. Treatment of 3-siloxy-1,3-diene-7-ynes with catalytic amounts of [W(CO)6] or [ReCl(CO)5] under photoirradiation conditions gives synthetically useful bicyclo[3.3.0]octane derivatives in good yields. Extremely high catalytic activity is noted for the rhenium(I) complex. The reaction has been extended to substrates containing a nitrogen atom in their tethers. In this case, two kinds of synthetically useful heterocyclic compounds-the 2-azabicyclo[3.3.0]octane derivatives 9 and the monocyclic dihydropyrroles 10, with allenyl substituents-are obtained, and selective preparation of either product can be achieved through the use of an appropriate combination of the nitrogen substituent and the type of the rhenium(I) catalyst. The 2-azabicyclo[3.3.0]octane derivatives 9 are obtained selectively by carrying out treatment of N-Ns derivatives in the presence of [ReCl(CO) 4(PPh3)], whereas the dihydropyrrole derivatives 10 are obtained by treatment of N-Mbs derivatives with [ReCl(CO)5]/ AgSbF6. Finally, we have applied this geminal carbo-functionalization to one-carbon-elongated substrates containing N-Ts moieties in their tethers. Selective 5-exo cyclization is achieved in the presence of gold(I) or rhenium(I) catalysts, whereas 6-endo cyclization is observed on use of [W(CO) 6]. Geminal carbo-functionalization of 3-siloxy-1,3-dien-7-ynes leading to bicyclo[3.3.0]octane derivatives is achieved through electrophilic activation of alkynes by tungsten(0) and rhenium(I) catalysts (see graphic). Extremely high activity is noted for rhenium(I) catalysts. Furthermore, selective preparation of two different classes of heterocyclic compounds from 5-aza-3-siloxy-1,3-dien-7-ynes is also achieved by appropriate choice of the rhenium(I) catalyst and the protecting group on the nitrogen. Copyright

Synthetic studies on and mechanistic insight into [W(CO) 5(L)]-catalyzed stereoselective construction of functionalized bicyclo[5.3.0]decane frameworks

Stereoselective preparation of a variety of synthetically useful functionalized bicyclo[5.3.0]decane derivatives was achieved by tandem cyclization of 3-siloxy-1,3,9-triene-7-yne derivatives based on the electrophilic activation of alkynes catalyzed by [W(CO)5(L)], The reaction proceeded smoothly under photoirradiation, and various substrates were cyclized to give the corresponding bicyclic compounds with up to four chiral centers stereospecifically. Reactions of siloxydienes with a silyl substituent as an equivalent of a hydroxyl group also proceeded with wide generality to afford silyl-substituted bicyclo[5.3.0]decanes, which were highly useful as synthetic intermediates. Stereochemical studies concerning the silyl enol ether moiety suggested that two types of reaction path way for the formation of seven-membered rings were present. The reaction of (Z)-enol silyl ethers proceeded through Cope rearrangement of cis-divinylcyclopropane intermediates, and that of (E)-enol silyl ethers by 1,4-addition of the dienyl tungsten species at the position δ to the metal atom. In the reactions of siloxydiene derivatives with silyl substituents, all possible diastereomers could be synthesized stereoselectively by changing the geometry of the silyl enol ether and enyne moieties.

Complexation-initiated intramolecular [4+2] cycloaddition: Construction of bridged-type cycloadducts

(Chemical Equation Presented) The characteristic structural features of [(alkyne)Co2(CO)6] complexes were used to achieve bridged-type intramolecular [4 + 2] cycloaddition reactions. The reaction of such complexes bearing a siloxydie

Rhenium(I)-catalyzed intramolecular geminal carbofunctionalization of alkynes: Tandem cyclization of ω-acetylenic dienol silyl ethers

(Chemical Equation Presented) Bicycle production: The low-valent rhenium complex [ReCl(CO)5] catalyzes a tandem intramolecular cyclization reaction of ω-acetylenic dienol silyl ethers. The alkyne undergoes a geminal carbofunctionalization in the presence of 0.5-3.0 mol % [ReCl(CO) 5] under photoirradiation to give bicyclic enol silyl ethers in high yields (see scheme, TIPS = triisopropylsilyl).