222
K. Selvam et al. / Applied Catalysis A: General 413–414 (2012) 213–222
Earlier we reported the formation of quinaldine from aniline in
ethanol with TiO2 [28].
Acknowledgements
Reusability of the catalyst was tested with the reaction of 4,4ꢀ-
azoxyanisole in aqueous methanol for three cycles. Yield of the
product decreases slightly in each cycle (I cycle – 88%, II cycle –
86%, III cycle – 85%). There is no significant decrease in yield after
third run.
Authors thank Prof. P.V. Satyam, IOP, Bhubaneswar, India for
HRTEM measurements. The author (M.S.) thanks Council of Sci-
entific and Industrial Research (CSIR), New Delhi, for the financial
support through research grant no. 21 (0799)/10/EMR-II. One of the
authors, K. Selvam is thankful to CSIR, New Delhi, for the award of
Senior Research Fellowship.
3.2.6. Plausible reaction mechanism
Appendix A. Supplementary data
GC–MS chromatograms recorded at different reaction times
of the photocatalytic conversion of 4,4ꢀ-azoxyanisole in aque-
ous methanol are presented in Fig. 8. GC–MS chromatograms
reveal the formation of 4,4ꢀ-dimethoxyazobenzene, p-anisidine,
4-methoxyformanilide as intermediates during the 5-methoxy-
2-(4-methoxyphenyl)-2H-indazole formation. The formation of
byproducts azobenzene and aniline is indicated by GC–MS chro-
converted into azo compounds by irradiation for 1 h and further
irradiation lead to 2-phenylindazoles. Based on the intermediates
identified by GC–MS during irradiation, a mechanism is proposed
(Scheme 1).
Supplementary data associated with this article can be found, in
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