2344-53-8Relevant articles and documents
Synthesis and characterization of propeller-shaped mono- to hexacationic quinolinium-substituted benzenes
Batsyts, Sviatoslav,Hübner, Eike G.,Namyslo, Jan C.,Gjikaj, Mimoza,Schmidt, Andreas
, p. 4102 - 4114 (2019)
Diels-Alder reaction of 2-, 3- and 4-(phenylethynyl)quinolines and tetraphenylcyclopentadienone gave three regioisomeric 2,3,4,5,6-pentaphenyl-1-(quinolin-2-yl, -3-yl, and -4-yl)benzenes. Restricted rotation of the 3-yl and 4-yl substituted derivatives is observed between the central core and the substituents, resulting in propeller-shaped molecules. Likewise, 1,2-diquinolinyl-3,4,5,6-tetraphenylbenzenes with 3-yl,3-yl and 3-yl,4-yl connectivity were prepared. As evidenced by NMR spectroscopy, they form two diasteromers due to their restricted rotation. A cobalt-catalyzed [2 + 2 + 2]-cyclotrimerization of 2-(phenylethynyl)quinoline resulted in the formation of triphenyl-2,4,6- and -3,5,6-tri(quinolin-2-yl)benzenes. The same reaction was applied to 3,3′-ethyne-1,2-diyldiquinoline which formed hexa(quinolin-3-yl)benzene. N-Methylation gave the title compounds. Among those, the hexacationic hexa(N-methylquinolinio-3-yl)benzene is described. Stereochemical aspects are predominantly discussed by means of results of NMR experiments. DFT-calculations on the most stable conformations and the frontier orbital profiles of the hexacation as well as of its neutral precursor have been carried out.
Photophysics of monodisperse platinum-acetylide oligomers: Delocalization in the singlet and triplet excited states
Liu, Yao,Jiang, Shujun,Glusac, Ksenija,Powell, David H.,Anderson, Danielle F.,Schanze, Kirk S.
, p. 12412 - 12413 (2002)
A series of monodisperse Pt-acetylide polymers that contain the [-C≡C-(p-C6H4)-C≡C-(t-Pt(PBu3)2)-]n repeat unit has been prepared for n = 1, 2, 3, 4, 5, and 7. The photophysical properties of the series provide information concerning the relationship between the oligomer length and delocalization in the singlet and triplet excited states of the π-conjugated electron system. The results imply that the singlet excited state is delocalized over approximately 6 repeat units; however, the triplet state is considerably more localized. The triplet energy is almost invariant with oligomer length, but the phosphorescence spectra and triplet nonradiative decay rates indicate that the electron-vibrational coupling in the triplet state decreases with increasing oligomer length. Copyright
Synthesis and Photochemistry of a New Photolabile Protecting Group for Propargylic Alcohols
Ma, Chi,Zhang, Youlai,Zhang, Huan,Li, Junru,Nishiyama, Yasuhiro,Tanimoto, Hiroki,Morimoto, Tsumoru,Kakiuchi, Kiyomi
, p. 560 - 564 (2017/03/11)
A new and efficient thiochromenone S,S-dioxide-based photolabile protecting group for propargylic alcohols is described. Robust protection reactions were developed through copper (II)-catalyzed substitution of propargylic alcohols. Subsequent photodeprote
