Green Chemistry
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H-bond network with its surrounding water molecules. Hence,
aromatic carbons in phloroglucinol are blocked from direct
hydrogenation. Instead, the hydrogen atom on the surface
tends to bond to the oxygen atom of the hydroxyl group and
breaks the C–O bond, which is already weakened upon
chemisorption on Pt, to form a water molecule. In contrast,
with the absence of one hydroxyl group in resorcinol, the
aromatic ring can be directly hydrogenated; the hydrogenation
step is then followed by dehydration to form phenol. The
References
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53.9 kJ mol− ) is only slight greater than that of direct hydro-
1
(
−
1
−1
genation of the ring (46.4 kJ mol or 42.4 kJ mol ), which
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(
−
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4
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−
1
pathways of resorcinol occur include hydrogenation to 17 L. C. Williams, C. Chang, P. Do, N. Nikbin, S. Caratzoulas,
−
1
1
,3-cyclohexanediol (E
a
= 46 kJ mol ) and hydrogenation/
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−
1
dehydration to phenol (E = 54 kJ mol ). For both reactions,
a
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−
1
phenol (E = 42 kJ mol ) produces cyclohexanone, which is
further hydrogenated (E
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−
1
a
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2
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Acknowledgements
Jin Yang and Paul Dauenhauer acknowledge support from
the 3M Corporation Nontenured Faculty Award. Ashwin 23 E. Furimsky, Appl. Catal., A, 2000, 199, 147–190.
Ramasubramaniam acknowledges startup support from the 24 T. P. Vispute, H. Y. Zhang, A. Sanna, R. Xiao and
University of Massachusetts Amherst.
G. W. Huber, Science, 2010, 330, 1222.
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