405064-56-4

Upstream product

• 558-13-4 carbon tetrabromide 
• 135-02-4 ortho-anisaldehyde 
• 1066-54-2 trimethylsilylacetylene 
• 767-91-9 1-ethynyl-2-methoxybenzene 
• 878199-28-1 1-(2-methoxyphenyl)-3-(trimethylsilyl)prop-2-yn-1-one 
• 153889-90-8 1-(2-methoxyphenyl)-3-(trimethylsilyl)prop-2-yn-1-ol 
• 529-28-2 4-iodoanisol 
• 4526-06-1 trimethylsilyl-1,3-butadiyne 
• 405064-49-5 [4,4-dibromo-3-(2-methoxyphenyl)-buten-1-ynyl]trimethylsilane 

Downstream Products

• 1094774-80-7 1-(buta-1,3-diyn-1-yl)-2-methoxybenzene 
• 1394290-83-5 1-methoxy-2-(6,6,6-trifluorohexa-1,3-diyn-1-yl)benzene 

Relevant academic research and scientific papers

Chemoselective Cobalt(I)-Catalyzed Cyclotrimerization of (Un)Symmetrical 1,3-Butadiynes for the Synthesis of 1,2,4-Regioisomers

The cobalt(I)-catalyzed cyclotrimerization of (un)symmetrical 1,4-disubstituted 1,3-butadiynes is presented. In the case of unsymmetrical 1,3-butadiynes, this reaction can generate eight 1,2,4-substituted and four 1,3,5-substituted isomers. A single 1,2,4-substituted isomer was formed in excellent yields (up to 99%) and exclusive regioselectivities (>99:1) when symmetrical or a 1,3-butadiyne with an aryl or alkyl substituent and a trimethylsilyl group were applied. A large number of products accepting a wide variety of functional groups were synthesized.

Control of the Regioselectivity in Cobalt- versus Ruthenium-Catalyzed Alder-ene Reaction of Unsymmetrical 1,3-Diynes

The Alder-ene reaction of trialkylsilyl-substituted 1,3-butadiynes with terminal alkenes was investigated utilizing a cobalt-based catalyst, and the results were compared with Alder-ene rections catalyzed by the [CpRu(H3CCN)3]PF6 catalyst. Obviously, the two catalysts gave complementary results of yn-dienes differing in the site where the new carbon-carbon bond was formed. Of particular interest are observations concerning the double bond migration within the alkene component. While simple alkenes gave exclusively the E-configuration, the application of 3-buten-1-ol resulted in the corresponding Z-double bond, indicating that the hydroxyl group acts as donor coordinating to the cobalt center and thereby altering the reaction pathway.

Syntheses of trifluoroethylated unsymmetrical 1,3-diynes by using 1,1-dichloro-2,2,2-trifluoroethane

Copper-mediated reaction of terminal 1,3-diynes with 1,1-dichloro-2,2,2-trifluoroethane (CF3CHCl2) using ethanolamine as ligand gave trifluoroethylated unsymmetrical 1,3-diynes in moderate to good yields. The reaction were carried out under mild conditions, and were easy to operate. Aryl groups with weak electron-withdrawing group or electron-donating group, and alkyl substitutents at terminal 1,3-diynes were tolerated. Synthesis of a trifluoroethylated conjugated triyne by using this method was demonstrated. Further transformation of the trifluoroethylated unsymmetrical 1,3-diyne to provide trifluoroethyl-substituted 1,2,3-triazole and isoxazole as application examples were successfully realized.

A straightforward synthesis of indole and benzofuran derivatives

A new methodology for the synthesis of indole and benzofuran derivatives has been devised. The starting materials, ortho-substituted aryl diynes, have been easily converted into new unsaturated bis-indolyl and bis-benzofuran derivatives and into 2-ethynylindole and 2-ethynylbenzofuran. Both these products have been further elaborated into more complex unsaturated indole-benzofuran and bis-benzofuran derivatives.

Synthesis of unsymmetrically substituted 1,3-butadiynes and 1,3,5-hexatriynes via alkylidene carbenoid rearrangements

Unsymmetrically substituted 1,3-butadiynes and 1,3,5-hexatriynes are synthesized in four steps from commercially available aldehydes or carboxylic acids. The key step in this process involves a Fritsch-Buttenberg-Wiechell rearrangement, in which an alkylidene carbenoid intermediate subsequently rearranges to the desired polyyne. This rearrangement proceeds under mild conditions, and it is tolerant of a range of functionalities. In general, the procedurally facile formation of the dibromoolefinic precursors, in combination with the effectiveness of the rearrangement step, makes this procedure an attractive alternative to traditional methods for di- and triyne synthesis that utilize palladium or copper catalysis.

Modification of the Fritsch-Buttenberg-Wiechell rearrangement: A facile route to unsymmetrical butadiynes

A modification of the Fritsch-Buttenberg-Wiechell rearrangement has been used to form unsymmetrically substituted 1,3-butadiynes from 1,1-dibromo-olefin precursors. The reaction proceeds via lithium-halogen exchange, followed by migration of the aryl or alkynyl moiety to provide the butadiyne framework. The facile formation of the dibromo-olefins in three steps from commercially available aryl aldehydes or carboxylic acid chlorides makes this procedure an attractive alternative to traditional methods for butadiyne synthesis.