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equivalents of N,N dimethylurea, 65% conversion was achieved
with the formation of the monocarbamate. A minor byproduct
(<12%) was not fully characterised, however mass spectrometry
evidence suggested it may be the disubstituted N,N dime-
thylcarbamate (Table 3).
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Experimental
The general method to convert diols to either the cyclic
carbonate or the diurethane was as follows: a mixture of diol
(0.066 mol), urea (0.132 mol) and 5% wt zinc monoglycerolate
(0.25 g) with respect to the diol, were heated to 140 ꢀC at a
reduced pressure of 40 mbar in a round bottom ask tted with
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This paper has highlighted the use of zinc monoglycerolate
being used as a homogeneous catalyst in the transformation of
1,2- and higher order diols to yield the cyclic carbonate or the
linear diurethane selectively in good yields (54–79%).
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Acknowledgements
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The authors are grateful to Micronisers Pty Ltd for supply of zinc
glycerolate nanoparticles, the Australian Research Council for
nancial support (Grant no.: DP1095129), the Faculty of Science
for providing an international PhD fees scholarship (US) and
wish to thank Mingdeng Luo and Sally Duck from Monash
University for instrumental support.
47812 | RSC Adv., 2015, 5, 47809–47812
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