125889-67-0Relevant academic research and scientific papers
Photochemical Reaction of 2,4,4,6-Tetraaryl-4H-Pyrans and -4H-Thiopyrans with Colour Change by a 1,5-Electrocyclic Reaction. X-Ray Molecular Structure of 4-Methyl-2,3,6-triphenyl-2H-thiopyran
Mori, Yukie,Maeda, Koko
, p. 2061 - 2066 (2007/10/02)
2,4,4,6-Tetraphenyl-4H-pyran and -4H-thiopyran exhibited a photochemical colour change in the solid state.On irradiation in solution, 2,4,4,6-tetraphenyl-4H-pyran gave 1,3,5,6-tetraphenyl-2-oxabicyclohex-3-ene, while the 4H-thiopyran gave 1,3,5,6-tetraphenyl-2-thiabicyclohex-3-ene as an initial photoproduct, followed by further transformation into 2,3,4,6-tetraphenyl-2H-thiopyran. 4-(4-Bromophenyl)-2,4,6-triphenyl-4H-pyran, 4-(4-methylphenyl)-2,4,6-triphenyl-4H-pyran, and 4-(bromophenyl)-2,4,6-triphenyl-4H-thiopyran also showed photochemical colour changes and finally gave both the phenyl-migrated and the (substituted phenyl)-migrated products in comparable yields in each case. 4-Methyl-2,4,6-triphenyl-4H-thiopyran showed no photochemical colour change in the solid state, but in solution it afforded 4-methyl-2,3,6-triphenyl-2H-thiopyran, whose structure was confirmed by X-ray analysis.Based on comparison with the photochemical behaviour of 2,4,4,6-tetraphenyl-1,4-dihydropyridine and 2,2,4,6-tetraphenyl-1,2-dihydro-1,3,5-triazine, a six-membered ylide was proposed as the coloured photochemical intermediate.
NMR SPECTROSCOPIC INVESTIGATION OF p-SUBSTITUTED 2,4,4,6-TETRAPHENYL-1,4-DIHYDROPYRIDINES AND THEIR OXA AND THIA ANALOGUES
Schwarz, Marian,Trska, Petr,Kuthan, Josef
, p. 1854 - 1869 (2007/10/02)
The 1H, 13C, 19F NMR spectra of photochromic p-substituted 2,4,4,6-tetraphenyl-1,4-dihydropyridines IIa-IIg, 1-methyl-2,4,4,6-tetraphenyl-1,4-dihydropyridines IIIa-IIIg, 2,4,4,6-tetraphenyl-4H-pyrans IVa-IVh, and 2,4,4,6-t
