344
W. H. Meyer et al. · Tri(3-pyridyl)phosphine as Amphiphilic Ligand in the Rhodium-catalysed Hydroformylation
submitted to a vacuum distillation to separate volatiles from or 261 nm (aqueous phase) to determine the phosphine
the catalyst and excess ligand. This solution was transferred concentration.
into a three-necked flask containing a suspension of a suffi-
cient amount (about 0.5 g) of LiAlH4 in 20 mL of ether to
reduce the formed aldehydes to the alcohols overnight. After
aqueous workup (pH ∼ 1) the alcohols as well as unreacted
alkenes were extracted three times into ether. The combined
organic phases were dried over MgSO4 and analysed via gas
chromatography using n-hexanol as a standard.
Recycling experiments were carried out with preforma-
tion (see above). After the catalysis the reaction mixture was
transferred to a Schlenk tube under argon and extracted three
times with 2×7 mL and 1×6 mL of distilled water of pH 1
(H2SO4). The remaining organic phase was dried and re-
duced with LiAlH4 as described above. The aqueous phase
(a part was kept for rhodium analysis) was neutralised using
Na2CO3 and extracted with toluene (7 mL, 7 mL, 6 mL) at
pH 6 for run 1 or at pH 9 after addition of NaAc for run 2. The
determination of the rhodium amounts was carried out via
ICP-AES after digesting all relevant rhodium residues with
aqua regia.
Computational details
All geometry optimisations were performed with the
DMol3 Density Functional Theory (DFT) code [30 – 32] as
implemented in the MaterialsStudioTM (Version 3.2) pro-
gram suite released by Accelrys Inc. The revised PBE non-
local generalised gradient approximation (GGA) exchange-
correlation functional of Hammer, Hanson and Nørskov [33]
(termed RPBE), was used throughout this study. DMol3
utilises a basis set of numeric atomic functions, which are
exact solutions to the Kohn-Sham equations for the atoms;
in the present study an all electron polarised split valence
basis set, termed double numeric polarised (DNP) has been
used [34]. All geometry optimisations employed highly effi-
cient delocalised internal coordinates [35]. T−he5 tolerance for
convergence of the SCF density was set to 10 Ha while the
tolerance for energy convergence was set to 2×10−6 Ha. Ad-
ditional convergence criteria include the tolerance for con-
verged gradient (4×10−4 Ha A−1) and the tolerance for con-
˚
The distribution coefficient of P(3-py)3 in water-
cyclohexane mixtures was determined at different final pH
values (H2SO4 as acid, NaOH as base) according to the pub-
lished formula [13]. Portions of 2 mL of the same amount
of P(3-py)3 in cyclohexane were shaken with 2 mL of wa-
verged atom displacement (5×10−4 A).
˚
Acknowledgement
The authors thank Jan-Albert van den Berg from Sasol
ter of a certain pH. After settling for about 15 min both Technology, R&D, Analytical Solutions for the molecular
phases were analysed via UV-vis at 259 nm (organic phase) modeling calculations.
[1] G. R. Newkome, Chem. Rev. 1993, 93, 2067.
[2] P. C. J. Kamer, J. N. H. Reek, P. W. N. M. van Leeuwen
in Aqueous-Phase Organometallic Catalysis, 2nd ed.
(Eds.: B. Cornils, W. A. Herrmann), Wiley-VCH,
Weinheim, 2004, pp. 686.
[3] M. S. Goedheijt, P. C. J. Kamer, J. N. H. Reek,
P. W. N. M. van Leeuwen in Aqueous-Phase
Organometallic Catalysis, 2nd ed. (Eds.: B. Cornils,
W. A. Herrmann), Wiley-VCH, Weinheim, 2004,
pp. 121.
[4] Q. Peng, Y. Yang, C. Wang, X. Liao, Y. Yuan, Catalysis
Lett. 2003, 88, 219.
[5] A. Solsona, J. Suades, R. Mathieu, J. Organomet.
Chem. 2003, 669, 172.
Kamer, P. W. N. M. van Leeuwen, J. Chem. Soc., Dal-
ton. Trans. 1996, 2143.
[11] R. H. Laitinen, J. Soininen, P. Suomalainen, T. A.
Pakkanen, M. Ahlgre´n, J. Pursiainen, Acta Chem.
Scand. 1999, 53, 335.
[12] A. Buhling, P. C. J. Kamer, P. W. N. M. van Leeuwen,
J. Mol. Catal. A 1995, 98, 69.
[13] A. Buhling, P. C. J. Kamer, P. W. N. M. van Leeuwen,
J. W. Elgersma, J. Mol. Catal. A 1997, 116, 297.
[14] K. Wajda, F. Pruchnik, T. Lis, Inorg. Chim. Acta 1980,
40, 207.
[15] K. Wajda-Hermanowicz, F. P. Pruchnik, Transition
Met. Chem. 1988, 13, 101.
[16] J. D. Atwood, Inorganic and Organometallic Reaction
Mechanisms, 2nd ed., Wiley-VCH, New York, 1997,
pp. 95.
[6] S. Bischoff, M. Kant, Catalysis Today 2001, 66, 183.
[7] M. S. Goedheijt, B. E. Hanson, J. N. H. Reek, P. C. J.
Kamer, P. W. N. M. van Leeuwen, J. Am. Chem. Soc.
2000, 122, 1650.
[17] A. L. Rheingold, S. J. Geib, Acta Cryst. 1987, C43,
784.
[8] M. Karlsson, M. Johansson, C. Andersson, J. Chem.
Soc., Dalton Trans. 1999, 4187.
[9] K. Kurtev, D. Ribola, R. A. Jones, D. J. Cole-Hamilton,
G. Wilkinson, J. Chem. Soc., Dalton Trans. 1980, 55.
[10] A. Buhling, J. W. Elgersma, S. Nkrumah, P. C. J.
[18] P. A. Chaloner, C. Claver, P. B. Hitchcock, A. M. Mas-
deu, A. Ruiz, Acta Cryst. 1991, C47, 1307.
[19] Y.-J. Chen, Y.-C. Wang, Y. Wang, Acta Cryst. 1991,
C47, 2441.
- 10.1515/znb-2007-0306
Downloaded from De Gruyter Online at 09/12/2016 10:53:39PM
via free access