Base-Induced Chemiluminescent Decomposition of Bicyclic Dioxetanes Bearing a (Benzothiazol-2-yl)-3-hydroxyphenyl Group: A Radiationless Pathway Leading to Marked Decline of Chemiluminescence Efficiency
作者:Masatoshi, Tanimura、Nobuko Watanabe、Hisako K. Ijuin、Masakatsu Matsumoto
DOI:10.1021/jo300417e
日期:2012.5.18
Charge-transfer-induced decomposition (CTID) of bicyclic dioxetanes 1b–d bearing a 3-hydroxylphenyl moiety substituted with a benzothiazol-2-yl group at the 2-, 6-, or 5-position was investigated, and their chemiluminescence properties were compared to each other, based on those for a 4-benzothiazolyl analogue 1a. Dioxetanes 1c and 1d underwent CTID to give the corresponding oxido anions of keto esters
Thermochemiluminescence of bicyclic dioxetanes bearing a 4-(benzazol-2-yl)-3-hydroxyphenyl moiety in solution and in the solid state
作者:Nobuko Watanabe、Ayumu Matsumoto、Kai Takanashi、Hisako K. Ijuin、Yoshio Kabe、Masakatsu Matsumoto
DOI:10.1016/j.tet.2023.133332
日期:2023.4
Uncatalyzed thermal decomposition of four bicyclic dioxetanes bearing a 4-(benzothiazol-2-yl)-3-hydroxyphenyl and their 4-(benzimidazol-2-yl) analogs effectively caused thermochemiluminescence (TCL) due to ESIPT (excited state intramolecular proton transfer) both in solution and in the solid state. The efficiency of TCL (ΦTCL) was ∼15 times higher in the solid state than in solution. This high ΦTCL
Bicyclic dioxetanes bearing a 4-(benzoazol-2-yl)-3-hydroxyphenyl moiety: chemiluminescence profile for base-induced decomposition in aprotic medium and in aqueous medium
Four bicyclic dioxetanes bearing a 4-(benzothiazol-2-yl)-3-hydroxyphenyl or 4-(benzoxazol-2-yl)-3-hydroxyphenyl group were synthesized. These dioxetanes underwent base-induced decomposition with accompanying emission of light with high efficiency in NaOH/H2O as well as in tetrabutyl ammonium fluoride (TBAF)/acetonitrile. Among them, benzothiazol-analogs decomposed faster in the aqueous solution than in acetonitrile. (c) 2005 Published by Elsevier Ltd.
Intramolecular Charge-Transfer-Induced Decomposition Promoted by an Aprotic Polar Solvent for Bicyclic Dioxetanes Bearing a 4-(Benzothiazol-2-yl)-3-hydroxyphenyl Moiety
作者:Masatoshi Tanimura、Nobuko Watanabe、Hisako K. Ijuin、Masakatsu Matsumoto
DOI:10.1021/jo1021822
日期:2011.2.4
Bicyclic dioxetanes 3a-d bearing a 4-(benzothiazol-2-yl)-3-hydroxyphenyl group decomposed to give the corresponding keto esters 4a-d accompanied by the emission of bright light when simply dissolved in an aprotic polar solvent such as N-methylpyrrolidone (NMP) or DMF at 50-100 degrees C. This solvent-promoted decomposition (SPD) was effectively a chemiluminescence process caused by the hydrogen bonding of a phenolic OH with a solvent molecule(s). The characteristics of the chemiluminescence in SPD resembled those in base-induced decomposition (BID), which occurs through an oxidoaryl-substituted dioxetane 5 by an intramolecular charge-transfer-induced decomposition (CTID) mechanism. Both free energies of activation, Delta G*(SPD) and Delta G*(BID), increased in the order 3a < 3b < 3c < 3d, and were linearly correlated with each other. However, SPD showed features different from those of BID in terms of enthalpy of activation and entropy of activation. SPD had large negative values for Delta S* (ca. -71 J mol(-1) K-1) regardless of the substituent Rat the 5-position for 3a-d, while the Delta S* values for BID changed from 0.5 to -22 J mol(-1) K-1 as R became smaller. The enthalpy of activation Delta H* for SPD was 14-21 kJ mol(-1) smaller than that for BID.