144079-25-4Relevant academic research and scientific papers
Time-resolved Spectroscopy and Charge-transfer Photochemistry of Aromatic EDA Complexes with X-Pyridinium Cations
Bockman, T. M.,Lee, K. Y.,Kochi, J. K.
, p. 1581 - 1594 (2007/10/02)
Direct photoexcitation of 1: 1 aromatic EDA complexes with various N-substituted X-pyridinium cations (X = nitro, fluoro, methoxy and acetoxy) is achieved by the specific irradiation of their charge-transfer (CT) absorption bands.Time-resolved picosecond spectroscopy refers to charge-transfer activation by the identification of the aromatic cation radical as the initial transient (T1) formed in a photoinduced electron-transfer together with the X-pyridinyl radical.The homolytic fragmentation of the latter varies with the X-substituent in the order X = NO2 > F > AcO >CH3O, and the addition of X. to the aromatic donors leads to a series of cyclohexadienyl adducts that are identified as longer-lived transients (T2) by time-resolved (nanosecond/microsecond) spectroscopy.The phototransients T1 and T2 together account for the different types of aromatic product (resulting from ring substitution, side-chain substitution and dimerization) that are generated by steady-state CT photochemistry of the aromatic EDA complexes with X-pyridinium cations.
