|Budget Amount *help
¥1,800,000 (Direct Cost : ¥1,800,000)
Fiscal Year 1997 : ¥500,000 (Direct Cost : ¥500,000)
Fiscal Year 1996 : ¥1,300,000 (Direct Cost : ¥1,300,000)
We have investigated the reaction path and the reaction mechanism for the chemiluminescent reaction of three-membered cyclic peroxides such as dimethyldioxirane and methyl (trifluoromethyl) dioxirane with 9-arylmethylene-10-methyl-9,10-dehydro-acridene to afford N-methylacridone and aromatic aldehydes with chemiluminescence.The steric effect of aryl substituents on the consumption rate of the olefin and the trapping experiments with methanol confirm that the first very reactive intermediate of the reaction is spiro [3-aryloxirane-2,9'- (10'-methyl-9', 10'-dihydroacridine) ]. The low-temperature NMR measurements of the rapid-quenched reaction solution and the comparison to the low-temperature NMR spectra of the corresponding 1,2-dioxetane indicate that the reaction of the second molecule of dimethyldioxirane with the oxirane intermediate gives spiro [3,3-dimethyl-5-aryl-1,2,4-trioxane-6,9'- (10'-methyl-9', 10'-dihydroacridine) ] as the chemiluminescint intermediate.
The first step of the
reaction is the Frontier-contolled reaction of dioxiranes with conjugated ene-tert-amines to afford enamine oxides as the first intermediate. The reaction of dioxiranes with enamin oxides is discussed on the stereochemical attacking direction and the change of the antibonding character in the perioxidec bond in view of the electrophilic reaction of dioxiranes by use of their LUMO and the nucleophilic reaction of dioxiranes by use of their HOMO.It is elucidated that the reactive enamine oxides as a polarized and large electrophile react Frontier-controlledly with the second molecule of dioxiranes as a nucleophile to give the chemiluminescent 1,2,4-trioxane. This reaction is the first reported example of the nucleophilic reaction of dioxiranes. The semi-emperical molecular orbital caluclation on HOMO,LUMO and the charge distribution of the transition state for the decomposition of the chemiluminescent 1,2,4-trioxanes indicate that the 1,2,4-trioxanes give the singlet-excited state of N-methylacridone on their decomposition by CIEEL mechanism. Less