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ChemComm
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DOI: 10.1039/C6CC01599A
Journal Name
COMMUNICATION
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M. Guerbet, C. R. Acad. Sci. Paris, 1899, 128, 1002; M. M.
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recycled three times and still produce isobutanol in good yield.
These results suggest that base deactivation may be a deciding
factor. Deactivation may also occur due to the formation of
water as the reaction proceeds. However, when water was
added at the start of a run (0.62 mL, 2 molar equivalents with
respect to ethanol) the catalyst was remarkably robust, the
same results within error being obtained compared to an
absence of initial water (compare runs 9 and 17).
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á
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In conclusion, we report an extremely selective and
productive homogeneous ruthenium catalyst for the
production of the advanced biofuel molecule isobutanol from
methanol-ethanol mixtures. Complexes supported by small
bite angle disphosphines give the best performance, with
preliminary mechanistic studies supportive of a Guerbet-type
mechanism.
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Notes and references
‡ When using sodium methoxide as the base the molar ratio of
methanol/methoxide:ethanol is 16.4.
§ Renan Cariou, Ian Dobson, Helen Mason, Glenn Sunley and
Russell Taylor (all BP) are thanked for useful discussions. BP
Biofuels Ltd and the EPSRC are thanked for funding.
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