Synthesis of symmetric triarylmethane derivatives catalyzed by AIL ionic liquid
Fig. 2 Weight at a function of T for TGA of AIL
Fig. 3 Yield as a function of run no.
Conclusion
layer containing the AIL was subjected to rotary evapora-
tion at 60 °C under reduced pressure to afford the
recovered AIL. Also, the catalyst could be reused easily six
times without apparent loss of activity in terms of yield
(85–83%; Fig. 3).
Over just a few years, there has been remarkable progress
for the synthesis of triarylmethanes. Here we have
demonstrated a facile AIL-catalyzed synthesis of sym-
metric triarylmethane derivatives from readily available
N,N-dimethylaniline or indole with different active aro-
matic aldehyde compounds. Hopefully the work described
here will stimulate further work for the synthesis of
unsymmetrical triarylmethanes.
All compounds were known and their physical data were
compared with those of authentic samples and found to be
identical.
Acknowledgements We are grateful to the Science and Technology
Foundation of Shanghai Institute of Technology for financial support.
Experimental
References
Melting points were measured on a WRS-IB digital melt-
1
ing point instrument. H NMR was recorded on AVANG
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To a mixture of aromatic aldehyde (2.0 mmol) and N,N-
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