Chemistry - A European Journal
10.1002/chem.201602133
COMMUNICATION
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In conclusion, we report a new, highly efficient protocol using
continuous flow technology for the in situ formation and the
direct use of ethyl lithiodiazoacetate from EDA. Difficulties with
the decomposition of ethyl lithiodiazoacetate were solved
through careful temperature control of the entire continuous flow
system. The system operated at low temperature (−78 °C) under
exclusion of air and water in an argon atmosphere. The method
gave excess to diversely substituted tertiary diazo alcohols
derived from ketones in moderate to good yields. A symmetrical
diazo alcohol was subsequently decomposed efficiently in
continuous flow conditions to give the seven-membered ketone
23 in excellent yield.
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Acknowledgements
Support from Pierre Fabre, France, and the School of Chemistry,
Cardiff University, is gratefully acknowledged. We thank the
EPSRC National Mass Spectrometry Facility, Swansea, for
mass spectrometric data. The support to TH and SE from the
Erasmus programme is gratefully acknowledged.
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Keywords: diazo compounds • flow chemistry • hazardous
intermediates • lithiation
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