177500-72-0

Upstream product

• 177500-70-8 Dimethyl-(4-{(E)-6-triisopropylsilanyl-3-[(triisopropylsilanyl)-ethynyl]-4-trimethylsilanylethynyl-hex-3-ene-1,5-diynyl}-phenyl)-amine 
• 186488-71-1 (E)-1,1-Dibromo-6-triisopropylsilanyl-3-[(triisopropylsilanyl)-ethynyl]-4-trimethylsilanylethynyl-hexa-1,3-dien-5-yne 
• 177500-66-2 (E)-3-Ethynyl-1,6-bis-triisopropylsilanyl-4-trimethylsilanylethynyl-hex-3-ene-1,5-diyne 
• 148367-68-4 (E)-1,1,6,6-tetrabromo-3,4-bis<(triisopropylsilyl)ethynyl>hexa-1,3,5-triene 
• 177500-73-1 Dimethyl-(4-{(Z)-4-(4-nitro-phenylethynyl)-6-triisopropylsilanyl-3-[(triisopropylsilanyl)-ethynyl]-hex-3-ene-1,5-diynyl}-phenyl)-amine 
• 636-98-6 p-nitrobenzene iodide 
• 186488-78-8 (4-{(E)-4-Ethynyl-6-triisopropylsilanyl-3-[(triisopropylsilanyl)-ethynyl]-hex-3-ene-1,5-diynyl}-phenyl)-dimethyl-amine 

Downstream Products

• 177500-73-1 Dimethyl-(4-{(Z)-4-(4-nitro-phenylethynyl)-6-triisopropylsilanyl-3-[(triisopropylsilanyl)-ethynyl]-hex-3-ene-1,5-diynyl}-phenyl)-amine 

Relevant academic research and scientific papers

Photochemical trans-cis isomerisation of donor/acceptor-substituted (E)-hex-3-ene-1,5-diynes (1,2-diethynylethenes, DEEs) and 3,4-diethynylhex-3-ene-1,5-diynes (tetraethynylethenes, TEEs)

The photochemically reversible trans-cis isomerisation of (E)-hex-3-ene-1,5-diynes (1,2-diethynylethenes, DEEs) and 3,4-diethynylhex-3-ene-1,5-diynes (tetraethynylethenes, TEEs) substituted with electron-donating (p-dialkylaminophenyl) and/or electron-accepting (p-nitrophenyl) groups has been examined. The type and degree of donor/acceptor (D/A) functionalisation has been found to drastically affect the partial quantum yields of isomerisation Φt→c and Φc→t. Total quantum yields in n-hexane vary from Φtotal = 0.72 for a bis-acceptor substituted TEE to Φtotal, = 0.015 for a four-fold, bis-donor, bis-acceptor substituted TEE derivative. A strong relationship between Φtotal and solvent polarity as well as a strong dependence of Φt→c and Φc→t on the wavelength of excitation λexc has been observed. The temperature dependence of the photoisomerisation has been investigated for a bis-acceptor-substituted DEE and shows no changes in Φtotal over the temperature range 6.5-65 °C. None of the compounds studied undergoes thermal isomerisation at 27 °C in n-hexane. Further analysis of these compounds by theoretical investigations at the semiempirical level of theory reveals a significant reduction of the bond order of the central olefinic double bond in the D-D, D-A and A-A TEEs upon electronic excitation, thus ultimately facilitating photoisomerisation.

186. Donor/acceptor-substituted tetraethynylethenes: Systematic assembly of molecules for use as advanced materials

A comprehensive series of tetraethynylethenes (= 3,4-diethynylhex-3-ene-1,5-diynes, TEEs) bearing electron-donating (p-methoxyphenyl or p-aminophenyl) and/or electron-accepting (p-nitrophenyl) groups was prepared via [Pd]-catalyzed Sonogashira cross-coupl