Photochemistry of 1-Aryl-4-(pentamethyldisilanyl)-1,3-butadiynes
摘要:
All the 1-aryl-4-(pentamethyldisilanyl)-1,3-butadiynes (1a-d) synthesized show strong phosphorescence emissions with triplet energies around 218-260 kJ/mol. Laser photolysis of 1-(p-nitrophenyl)-4-(pentamethyldisilanyl)-1,3-butadiyne (1d) in polar solvents results in the formation of an interesting transient (zwitterion species) through intramolecular electron transfer from disilanyl to the nitro group in the triplet excited state. Irradiation of 1d in methanol or ethanol gives 1-(p-nitrophenyl)-1,3-butadiyne (8) through C-Si bond cleavage from the transient. Photolysis of 1-phenyl-4-(pentamethyldisilanyl)-1,3-butadiyne (1a), 1-(1-naphthyl)-4-(pentamethyldisilanyl)-1,3-butadiyne (1b), and 1-(p-methoxyphenyl)-4-(pentamethyldisilanyl)-1,3-butadiyne (1c) in methanol yields photoaddition products (2-7) through silacyclopropene intermediates.
All the 1-aryl-4-(pentamethyldisilanyl)-1,3-butadiynes (1a-d) synthesized show strong phosphorescence emissions with triplet energies around 218-260 kJ/mol. Laser photolysis of 1-(p-nitrophenyl)-4-(pentamethyldisilanyl)-1,3-butadiyne (1d) in polar solvents results in the formation of an interesting transient (zwitterion species) through intramolecular electron transfer from disilanyl to the nitro group in the triplet excited state. Irradiation of 1d in methanol or ethanol gives 1-(p-nitrophenyl)-1,3-butadiyne (8) through C-Si bond cleavage from the transient. Photolysis of 1-phenyl-4-(pentamethyldisilanyl)-1,3-butadiyne (1a), 1-(1-naphthyl)-4-(pentamethyldisilanyl)-1,3-butadiyne (1b), and 1-(p-methoxyphenyl)-4-(pentamethyldisilanyl)-1,3-butadiyne (1c) in methanol yields photoaddition products (2-7) through silacyclopropene intermediates.
Photochemistry of 1-aryl-4-(pentamethyldisilanyl)buta-1,3-diynes: photoreaction with acetone and dimethyl fumarate
作者:Sang Chul Shim、Seong Taek Lee
DOI:10.1039/p29940001979
日期:——
(4–8)via silacyclopropene intermediates. Photoreaction of 1-aryl-4-(pentamethyldisilanyl)buta-1,3-diynes with dimethylfumarate gives two-atom insertion products (9 and 13)via silacyclopropene and/or [2 + 2] photocycloaddition products (10–12 and 14). The silacyclopropene intermediates are formed from singlet excited states in compounds 1 and 2, but from the triplet excited state in compound 3.