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Organic & Biomolecular Chemistry
Page 5 of 6
Journal Name
COMMUNICATION
proposed Path-A as minor approach for this transformation. and S) and ring size (five and six-member) which also gives
DOI: 10.1039/C7OB03064A
While in Path-B, the intermediate (V) was not detected in LC- additional advantage of the method.
MS but this step is not ignorable because both the
intermediates (VI) and (VIII) were detected by LC-MS. Further,
as we know that 2,2-dihydroxy-N-phenyl acetamide is a known
Acknowledgements
We are thankful to the Director, CSIR-IHBT for providing
necessary facilities. The authors are also thanks to CSIR, New
2
0
molecule
dihydroxyacetamide (
therefore,
diol-N-(2-aminophenyl)-2,2-
V
) could be possible intermediate, which
can be formed by the hemiacetal formation of intermediate (
I
)
)
)
th
Delhi for financial support as part of XII Five Year Plan
under acidic environment. In some cases, a clear mass of (
X
programme under title ORIGIN (CSC-0108) and MLP-0066 for
financial support. S. S. and D. B. thanks to CSIR, New Delhi for
awarding fellowships.
was detected in traces with corresponding intermediates (VIII
and (IX), indicated a minor Path-C for the by-product (
an unavoidable witness of intermediate ( ).
X
) and
V
CSIR-IHBT communication no. 4155
Notes and references
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information). The intermediate (V) can give the hydrogenated
4
5
product (VI) (detected in LC-MS) which through dehydrative
cyclization approach can give intermediate (VII). Since
21
methylene diol could be a good leaving group and participate
in aromatization reaction through elimination of methanediol
from intermediate (VII) to give the desired product 1H-
benzoimidazole (2a).
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1
1
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5
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