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Chemical Science
activity in the Knoevenagel condensation of benzaldehyde and
malononitrile.
Acknowledgements
Powder X-ray diffraction (XRD) patterns were acquired with This work was supported by ETH Zurich (research grant ETH-31
a PANalytical X’Pert PRO-MPD diffractometer using Ni-ltered 13-1) and the Swiss National Science Foundation (project
Cu Ka radiation (l ¼ 0.1541 nm). Data were recorded in the number 200021-134572).
ꢁ ꢁ
q range of 5–70 with an angular step size of 0.05 and a
2
counting time of 8 s per step. The relative crystallinity of the
faujasite samples was determined according to ASTM stan-
dard D3906. Si and Al concentrations in the solids were
determined by inductively coupled plasma optical emission
spectroscopy (ICP-OES) by using a Horiba Ultima 2 instru-
ment equipped with photomultiplier tube detection. Nitrogen
Notes and references
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A: Chem., 2002, 182–183, 327.
ꢁ
sorption at ꢀ196 C was carried out in a Micromeritics
TriStar II instrument. Prior to the measurement, the samples
ꢁ
were evacuated at 300 C for 3 h. The total surface area (SBET
)
was determined by the BET method and the t-plot method
was used to discriminate between micro- and mesoporosity.
The protocols for other applied characterisations are detailed
in the ESI.†
4 (a) K. Tanabe and W. F. H ¨o lderich, Appl. Catal., A, 1999, 181,
399; (b) H. Hattori, Appl. Catal., A, 2001, 222, 247; (c)
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Knoevenagel condensations with malononitrile were
3
carried out in a Radleys Carousel 6+ equipped with 50 cm
5 (a) Y. Ono, J. Catal., 2003, 216, 406; (b) H. Hattori, Chem. Rev.,
1995, 95, 537; (c) A. Corma and S. Iborra, in Fine Chemicals
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van Bekkum, Wiley-VCH, New York, 2002, vol. 1, p. 309.
6 D. Barthomeuf, Catal. Rev. Sci. Eng., 1996, 38, 521.
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2010, 22, 130; (c) S. Ernst, M. Hartmann, T. Hecht,
P. Cremades Ja ´e n and S. Sauerbeck, Stud. Surf. Sci. Catal.,
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two-necked round-bottom asks and reux cooling under a
nitrogen atmosphere. In a typical experiment, equimolar
amounts (4 mmol) of aldehyde and malononitrile, decane as
the internal standard (6 mmol), and pre-dried catalyst (50 mg)
3
ꢁ
were reacted in 30 cm of toluene at 80 C for 4 h under time-
resolved sampling. For the screening of alkaline-treated
USY385 zeolites (Fig. 3), the reaction temperature was lowered
ꢁ
to 60 C to reduce the conversion levels. The catalytic tests of
aldehydes with different kinetic diameters were carried out at
room temperature, the reaction time was adapted for each
substrate according to Table S2.† Solvent-free liquid-phase
3
reactions were carried out in Ace pressure tubes (15 cm , front
seal). In
a
typical experiment, an activated methylene
9 (a) X. Wang, K. S. K. Lin, J. C. C. Chan and S. Cheng, J. Phys.
Chem. B, 2005, 109, 1763; (b) A. Corma, R. M. Martin-Aranda
and F. Sanchez, J. Catal., 1990, 126, 192.
compound, aldehyde, internal standard and pre-dried catalyst
were heated to reaction temperature and le to react for the
desired reaction time. Then, the reaction was quenched by 10 (a) G. V. Shanbhag, M. Choi, J. Kim and R. Ryoo, J. Catal.,
cooling and diluted in acetone. The exact reaction conditions
are listed in Table S3.† Samples were analysed using a HP
2009, 264, 88; (b) D. Verboekend, T. C. Keller, S. Mitchell
and J. P ´e rez-Ram ´ı rez, Adv. Funct. Mater., 2013, 23, 1923.
Agilent 6890 gas chromatograph equipped with an HP-5 11 (a) D. Verboekend, G. Vil ´e and J. P ´e rez-Ram ´ı rez, Adv. Funct.
column and an FID detector. Due to the high boiling point,
the conversion of 9-phenanthrenealdehyde was determined by
Mater., 2012, 22, 916; (b) D. Verboekend, S. Mitchell,
M. Milina, J. C. Groen and J. P ´e rez-Ram ´ı rez, J. Phys.
Chem. C, 2011, 115, 14193; (c) J. P ´e rez-Ram ´ı rez,
D. Verboekend, S. Abell ´o and A. Bonilla, Adv. Funct.
Mater., 2009, 19, 3972.
ꢀ
1
ATR investigation of the C]O stretching band at 1695 cm
on a Bruker Vertex 70 spectrometer by coaddition of 96 scans
ꢀ1
with a resolution of 2 cm . Conversion and selectivity for all
reactions are reported with respect to the limiting aldehyde. 12 (a) A. C. Cope, J. Am. Chem. Soc., 1937, 59, 2327; (b)
The gas-phase aldol condensation of propanal was carried out
at atmospheric pressure in a continuous-ow xed-bed reactor
D. T. Mowry, J. Am. Chem. Soc., 1945, 67, 1050; (c)
S. L. Hruby and B. H. Shanks, J. Catal., 2009, 263, 181.
(internal diameter of 12 mm) using 0.3 g of catalyst (particle 13 (a) A. W. Chester, Y. F. Chu, R. M. Dessau, G. T. Kerr and
size ¼ 0.2–0.4 mm). Prior to the reaction, the catalyst was
C. T. Kresge, J. Chem. Soc., Chem. Commun., 1985, 289; (b)
J. R. Huon, D. M. Ruthven and R. P. Danner, Microporous
Mater., 1995, 5, 39; (c) D. F. Shantz, J. S. auf der G u¨ nne,
H. Koller and R. F. Lobo, J. Am. Chem. Soc., 2000, 122,
6659; (d) S. B. Hong and M. A. Camblor, Chem. Mater.,
1997, 9, 1999; (e) D. H. Olson, W. O. Haag and
W. S. Borghard, Microporous Mesoporous Mater., 2000, 35–
36, 435.
ꢁ
ꢁ
ꢀ1
activated at 450 C (heating rate ¼ 10 C min ) for 1 h under
3
ꢀ1
a 50 cm min He ow. Propanal was fed into the reactor
3
ꢀ1
using a syringe pump at 1.2 cm h via a vaporisation line.
Reactions were conducted at 400 C in a 50 cm min He
ow. The reaction mixture was analysed by an on-line HP
ꢁ
3
ꢀ1
Agilent 6890 gas chromatograph equipped with an HP-5
column and an FID detector.
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