RSC Advances
Paper
VI
[
Mo O
2
(ap-bhz)(MeOH)] 1 was treated with one drop portions
Acknowledgements
of 30% aqueous H O (0.066 g, 0.58 mmol) dissolved in 10 mL of
2
2
methanol and the resultant spectroscopic changes are pre- NS acknowledge MHRD fellowship and nancial support
sented in Fig. 10. A considerable increase in the intensity of the through Indian Institute of Technology Roorkee, India.
206 nm band and a broadening along with increase in intensity
of 226 and 251 nm bands were observed [Fig. 10(a)]. Another
prominent band at 295 nm shows increase in intensity without
any shi in position with successive addition of 30% aqueous
References
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reduction in intensity possibly due to the formation of corre-
12
VI
2+
sponding peroxido species. Other [Mo O
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]
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VI
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corresponding [Mo O(O )] complexes. Thus, reaction of H O
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VI
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7
Conclusions
VI
Dioxidomolybdenum(VI) complexes, [Mo O
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(ap-bhz)(MeOH)] 1,
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VI
VI
[
[
Mo O (ap-inh)(MeOH)] 2, [Mo O (ap-nah)(MeOH)] 3 and
2 2
VI
Mo O (ap-fah)(MeOH)] 4, and their corresponding oxidoper-
2
VI
oxidomolybdenum(VI) complexes, [Mo O(O
2
)(ap-bhz)(MeOH)]
)(ap-nah)(MeOH)]
)(ap-fah)(MeOH)] 8 have been prepared from
VI
VI
5
7
, [Mo O(O
2
)(ap-inh)(MeOH)] 6, [Mo O(O
2
VI
and [Mo O(O
2
potential tridentate hydrazones of 4-acetyl-3-methyl-1-phenyl-5-
pyrazolone, H ap-bhz I, H ap-inh II, H ap-nah III and H ap-fah
IV and characterized. Single crystal X-ray study of two Mo O
2
2
2
2
VI
2
-
VI
complexes and two Mo O(O )-complexes further conrm their
2
structures. These complexes are very efficient homogenous
catalyst precursors for the Hantzsch condensation reaction
under solvent free condition. Reaction of methylacetoacetate,
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3
phenylpyridine-3,5-dicarboxylate (b). Obtained conversion is
ꢁ
highest at 40 C with a : b selectivity ratio of ca. 10 : 90. This
ꢁ
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ˇ
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2 2
complex 3 with benzaldehyde in MeOH shows observable
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13008 | RSC Adv., 2016, 6, 12993–13009
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