CHEMCATCHEM
COMMUNICATIONS
1
trans-Stilbene: H NMR (CDHCl2): d=7.55–7.51 (4H, CH), 7.39 À7.33
Keywords: alkynes
complexes · rhodium · selective hydrogenation
·
homogeneous catalysis
·
hydride
(4H, CH), 7.29–7.25 (2H, CH), 7.14 ppm (2H, CH). 13C NMR (CD2Cl2):
d=137.65 (C), 129.01 (CH), 128.88 (CH), 127.97 (CH), 126.79 ppm.
1
cis-1-(4-Styrylphenyl)ethanone: H NMR (CDHCl2): d=7.82–7.79 (CH,
phenyl), 7.35–7.33 (2H, CH, phenyl), 7.26 (5H, CH), 2.25 ppm (3H,
CH3). 13C NMR (CD2Cl2): d=197.5 (C), 142.5 (C), 137.0 (C), 135.9 (C),
132.5 (CH), 129.4 (CH), 129.2 (CH), 129.1 (CH), 128.6 (CH), 128.4
(CH), 127.7 (CH), 26.6 ppm (CH3). GC–MS (EI, 70 eV): m/z (%)=222
(65) [M]+, 207 (100), 178 (70), 152 (15), 89 (9), 76 (6), 43 (8). Rf =
0.42 (ethyl acetate/n-hexane 10:90). HR-MS (EI): theoretical for
C14H12: 222.1039; found: 222.1040 [M]+.
[1] J. Scheirs, D. B. Priddy, Modern Styrenic Polymers: Polystyrenes and Styr-
enic Polymers, Wiley, Chichester, 2003.
[2] R. H. Grubbs, Handbook of Metathesis, Wiley-VCH, Weinheim, 2003.
[4] A. L. Reznichenko, K. C. Hultzsch, “Asymmetric Hydroamination”, in
“Chiral Amine Synthesis: Methods, Developments and Applications” (Ed.:
T. Nugent), Wiley-VCH, Weinheim, 2010, chapter 10, pp. 341–372.
[6] a) P. Hauwert, R. Boerleider, S. Warsink, J. J. Weigand, C. J. Elsevier, J. Am.
4-Chlorostilbene: The separation of both isomers occurred by
a bulb-to-bulb Kugelrohr distillation. Firstly, the cis-4-chlorostilbene
was observed as a colourless oil, then trans-4-chlorostilbene as
a white solid (vacuum, 758C). HR-MS (EI): theoretical for C14H12:
214.0538; found: 214.0543 [M]+. IR: n˜ =3020, 2924, 1488, 1448,
1405, 1087, 1073, 966, 816 (uCÀCl), 751, 689, 527 cmÀ1. Rf =0.77
(ethyl acetate/n-hexane 20:80).
cis-4-Chlorostilbene: 1H NMR (CD3OD): d=7.0–7.18 (9H, CH,
phenyl), 6.4–6.6 ppm (2H, CH, double bond). 13C NMR (CD3OD): d=
138.3 (C), 137.3 (C), 133.8 (C), 132.2 (CH), 131.5 (CH), 130.0 (CH),
129.9 (CH), 129.4 (CH), 129.3 (CH), 128.4 ppm (CH). GC–MS (EI,
70 eV): m/z (%)=214 (68) [M]+, 199 (8), 178 (100), 151 (12), 89 (15),
76 (15), 51 (6).
[8] J. A. Osborn, F. H. Jardine, J. F. Young, G. Wilkinson, J. Chem. Soc. A
[10] a) R. Malacea, E. Manoury, L. Routaboul, J.-C. Daran, R. Poli, J. P. Dunne,
trans-4-Chlorostilbene: 1H NMR (CDHCl2): d=7.55–7.44 (5H, CH,
phenyl), 7.40–7.24 (4H, CH, phenyl), 7.1 ppm (2H, CH, double
bond). 13C NMR (CD2Cl2): d=137.4 (C), 136.4 (C), 133.4 (C), 129.7
(CH), 129.2 (CH), 129.1 (CH), 128.3 (CH), 128.1 (CH), 127.6 (CH),
126.9 ppm (CH). GC–MS (EI, 70 eV): m/z (%)=214 (69) [M]+, 179
(100), 178 (87), 177 (22), 176 (17), 152 (14), 89 (19), 88 (12), 76 (17),
75 (12), 63 (10).
[12] R. R. Burch, A. J. Shusterman, E. L. Muetterties, R. G. Teller, J. M. Williams,
[15] a) C. Kohrt, W. Baumann, A. Spannenberg, H.-J. Drexler, I. Gridnev, D.
7383; c) C. Fischer, C. Kohrt, H.-J. Drexler, W. Baumann, D. Heller, Dalton
1
Diethyl maleate: H NMR (CDCl3): d=6.18 (2H, double bond), 4.20
(4H, CH2), 1.25 (6H, CH3). 13C NMR (CDCl3): 165.2 (C), 129.7 (CH),
61.1 (CH2), 13.9 ppm (CH3). GC–MS (EI, 70 eV): m/z (%)=172 (0.02)
[M]+, 127 (25), 99 (100), 54 (11), 29 (21).
cis-Prop-1-enylbenzene: 1H NMR ([D8]THF): d=7.22 (5H, CH,
phenyl), 6.41 (1H, CH), 5.73 (1H, CH, double bond), 1.86 ppm (3H,
CH3). 13C NMR ([D8]THF): d=138.7 (C), 131.4 (CH), 129.8 (CH), 129.0
(CH), 127.4 (CH), 127.2 (CH), 15.0 ppm (CH3). GC–MS (EI, 70 eV): m/z
(%)=118 (72) [M]+, 117 (100), 115 (44), 103 (10), 91 (32), 89 (8), 77
(9), 63 (11), 51 (13), 39 (13).
[16] The use of these complexes in the asymmetric hydrogenation of pro-
chiral olefins such as dimethyl itaconate shows a strong induction
period (Figure S1). This could be because the trinuclear complex is inac-
tive for such types of substrates and needs some time to convert into
the active species.
(E)-But-1-ene-1,4-diyldibenzene: GC–MS (EI, 70 eV): m/z (%)=208
(14) [M]+, 117 (100), 91 (33), 77 (4), 65 (15), 51 (5), 39 (6).
(E)-1,4-Diphenylbut-2-ene: GC–MS (EI, 70 eV): m/z (%)=208 (7)
[M]+, 130 (42), 117 (100), 104 (20), 91 (43), 77 (11), 65 (15), 51 (11),
39 (10).
[17] The analysis according to Michalis–Menten-type kinetics is exemplarity
shown in Figure S3.
[18] H.-J. Drexler, A. Preetz, T. Schmidt, D. Heller, “Kinetics of Homogeneous
Hydrogenations: Measurements and Interpretation” in “The Handbook of
Homogeneous Hydrogenation” (Ed.: J. G. de Vries, C. J. Elsevier), Wiley-
VCH, Weinheim, 2007, chapter 10, pp. 257–288.
1,2,3,4-Tetrabenzylidenecyclobutane: GC–MS (EI, 70 eV): m/z (%)=
408 (100) [M]+, 317 (92), 252 (16), 204 (24), 165 (8), 91 (7).
[19] G. M. Sheldrick, Acta Cryst. 2008, A64, 112–122.
Acknowledgements
Received: April 30, 2013
The authors thank the DFG for financial support.
Published online on July 19, 2013
ꢀ 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
ChemCatChem 2013, 5, 2818 – 2821 2821