array detector, or by CSP-GC on a Hewlett Packard 6890 GC
equipped with an autosampler and a flame ionization detector.
Determination of the branched-to-linear ratios was achieved by
GC-MS on a Agilent 6890 GC-MS using a capillary column HP-5.
ATR-IR spectra were recorded with a Perkin-Elmer 1650 FT-IR
spectrometer using a diamond ATR Golden Gate sampler.
b-Ketoesters 3a, 3c, 3d, 3f and 3g were prepared by DMAP-
catalyzed addition of the corresponding allylic alcohols to
diketene.21 b-Ketoesters 3b, 3e and 3h were prepared using a
transesterification procedure. A scheme showing the preparation
of these starting materials is included in the ESI.†
2 M. Shibasaki, H. Sasai and T. Arai, Angew. Chem., Int. Ed. Engl.,
1997, 36, 1236; M. Shibasaki, M. Kanai and K. Funabashi, Chem.
Commun., 2002, 1989; M. Shibasaki, S. Matsunaga and N. Kumagai,
Synlett, 2008, 1583.
3 J. A. Ma and D. Cahard, Angew. Chem., Int. Ed., 2004, 43, 4566; M.
Shibasaki and Y. Yamamoto, Multimetallic catalysts in organic syn-
thesis, Wiley-VCH, Weinheim, 2004; H. Yamamoto and K. Futatsugi,
Angew. Chem., Int. Ed., 2005, 44, 1924.
4 G. L. Hamilton, E. J. Kang, M. Mba and F. D. Toste, Science, 2007,
317, 496; M. Rueping, A. R. Antonchick and C. Brinkmann, Angew.
Chem., Int. Ed., 2007, 46, 6903.
5 R. Noyori and M. Kitamura, Angew. Chem., Int. Ed. Engl., 1991, 30,
49; M. Kanai, N. Kato, E. Ichikawa and M. Shibasaki, Synlett, 2005,
1491; T. Ikariya, K. Murata and R. Noyori, Org. Biomol. Chem., 2006,
4, 393.
Compounds 3a–3h and 7 have spectral characteristics identical
to those already described in the literature.7a,f
6 B. M. Trost, J. Org. Chem., 2004, 69, 5813; J. T. Mohr and B. M. Stoltz,
Chem.–Asian J., 2007, 2, 1476; Z. Lu and S. Ma, Angew. Chem., Int.
Ed., 2008, 47, 258 and references therein.
Cinnamyl prop-1-en-2-yl carbonate (6). Cinnamyl prop-1-
en-2-yl carbonate (6) was synthesised following a literature
procedure22 and obtained as a colorless oil. 1H NMR (500 MHz,
CDCl3) d: 7.50–7.30 (m, 5H), 6.80 (d, 3J(H–H) = 16 Hz, 1H), 6.40
7 (a) E. C. Burger and J. A. Tunge, Org. Lett., 2004, 6, 2603; (b) E. C.
Burger and J. A. Tunge, Chem. Commun., 2005, 2835; (c) T. Graening
and J. F. Hartwig, J. Am. Chem. Soc., 2005, 127, 17192; (d) H. He,
X. J. Zheng, U. Yi, L. X. Dai and S. L. You, Org. Lett., 2007, 9, 4339;
(e) D. J. Weix and J. F. Hartwig, J. Am. Chem. Soc., 2007, 129, 7720;
(f) S. Constant, S. Tortoioli, J. Muller and J. Lacour, Angew. Chem., Int.
Ed., 2007, 46, 2082; (g) S. Constant, S. Tortoioli, J. Muller, D. Linder,
F. Buron and J. Lacour, Angew. Chem., Int. Ed., 2007, 46, 8979.
8 E. P. Ku¨ndig and F. R. Monnier, Adv. Synth. Catal., 2004, 346, 901; A.
Labonne, L. Zani, L. Hintermann and C. Bolm, J. Org. Chem., 2007,
72, 5704.
3
3
2
(dt, J(H–H) = 16 Hz, J(H–H) = 6.5 Hz, 1H), 4.93 (d, J(H–
3
4
H) = 1.5 Hz, 1H), 4.88 (dd, J(H–H) = 7 Hz, J(H–H) = 1 Hz,
2H), 4.82–4.76 (m, 1H), 2.07 (d, 2J(H–H) = 1 Hz, 3 H). 13C NMR
(125 MHz, CDCl3) d: 153.0 (1C), 152.9 (1C), 136.0 (1C), 135.2
(1C), 128.7 (2C), 128.3 (1C), 126.8 (2C), 122.1 (1C), 102.0(1C),
68.7 (1C), 19.2(1C). MS (EI): 218 (1), 174 (3), 117 (100), 115 (25).
ATR-IR (neat): 1747, 1672, 1447, 1378, 1269, 1198 966, 931, 741,
691 cm-1. Low-resolution ESI-MS: 218 (1%), 117 (100%). Please
see the ESI for the GC-MS trace and 1H and 13C NMR spectra.†
9 D. Linder, F. Buron, S. Constant and J. Lacour, Eur. J. Org. Chem.,
2008, 5778.
10 For leading references on Cp*Ru-catalyzed allylic substitutions see: C.
Bruneau, J. L. Renaud and B. Demerseman, Chem.–Eur. J., 2006, 12,
5178; R. Hermatschweiler, I. Fernandez, P. S. Pregosin and F. Breher,
Organometallics, 2006, 25, 1440; B. M. Trost, P. L. Fraisse and Z. T.
Ball, Angew. Chem., Int. Ed., 2002, 41, 1059 and references therein.
11 C. Pettinari, F. Marchetti, A. Drozdov, J. A. McCleverty and T. J.
Meyer, in [beta]-Diketones and Related Ligands, Oxford, 2003,
p. 97.
CpRu-Catalyzed Carroll rearrangement—dual-catalysis procedure
In a typical procedure, in a 2 mL screw-cap vial equipped with
6
a magnetic stirring bar, [CpRu(h -naphthalene)][PF6] 1 (5.3 mg,
12 Acid Catalysis in Modern Organic Synthesis, ed. H. Yamamoto and
0.012 mmol, 2 mol%) and ligand 2 (8.1 mg, 0.033 mmol, 4.4 mol%)
were dissolved in 0.6 mL dry THF. The vial was flushed with
argon and capped. After heating for 1 h at 60 ◦C, the vial
was cooled to room temperature (~25 ◦C) and allyl b-ketoester
3a (150 mg, 0.6 mmol) was added in one portion followed by
Mg(OTf)2 (2.0 mg, 0.006 mmol, 1 mol%) and the vial was flushed
again with argon and stirred at room temperature for 24 h. The
cooled reaction mixture was diluted with 1.5 mL of ether–pentane
(60 : 40). After precipitation, the metal salts were filtered off on
a short SiO2 column (0.5 cm ¥ 4 cm, elution ether–pentane, 60 :
40); the solvents were then evaporated under reduced pressure to
afford the crude reaction mixture (4a + 5a) as a pale yellow oil
which was analysed (1H NMR, GC-MS, CSP-GC, ORD) without
further purification. Compounds 4a–4f, 5g and 4h have already
been reported in the literature and all general data collected fit the
previous description.7,23
K. Ishihara, Wiley-VCH, Weinheim, Germany, 2008.
13 This shows that the observed reactivity of the metal triflate salts is not
due to a possible Brønsted acid contamination.
14 No glove box manipulation of reagents needed.
15 These diastereoisomers result from the presence of a novel stereogenic
center a to the ketone carbonyl moiety.
16 Determined from the crude reaction mixture in CDCl3 (c ~ 1).
17 (S)-7 was prepared by olefination of commercially available enan-
tiopure styrene oxide using the protocol developed by Mioskowski
et al. and then subjected to an esterification with diketene (ee >
99%, CSP-HPLC). For the olefination, see: L. Alcaraz, J. J. Harnett,
C. Mioskowski, J. P. Martel, T. Legall, D. S. Shin and J. R. Falck,
Tetrahedron Lett., 1994, 35, 5449.
18 R. Hermatschweiler, I. Fernandez, F. Breher, P. S. Pregosin, L. F. Veiros
and M. J. Calhorda, Angew. Chem., Int. Ed., 2005, 44, 4397.
19 ent-2 and 2 are the ligands of (3S,8R) and (3R,8S) configuration
respectively.
20 For the use of Mg cations in the catalytic activation processes see: Y.
Kiyotsuka, H. P. Acharya, Y. Katayama, T. Hyodo and Y. Kobayashi,
Org. Lett., 2008, 10, 1719; R. W. Coscia and T. H. Lambert, J. Am.
Chem. Soc., 2009, 131, 2496 and references therein.
21 I. Collado, C. Pedregal, A. Mazon, J. F. Espinosa, J. Blanco-Urgoiti,
D. D. Schoepp, R. A. Wright, B. G. Johnson and A. E. Kingston,
J. Med. Chem., 2002, 45, 3619.
22 T. Nishimata, Y. Sato and M. Mori, J. Org. Chem., 2004, 69,
1837.
23 M. Fujii, K. Nakamura, S. Yasui, S. Oka and A. Ohno, Bull. Chem.
Soc. Jpn., 1987, 60, 2423; M. Morita, S. Sakaguchi and Y. Ishii, J. Org.
Chem., 2006, 71, 6285.
Notes and references
1 E. N. Jacobsen, A. Pfaltz and H. Yamamoto, Comprehensive asym-
metric catalysis, Springer, Berlin, New York, 1999; I. Ojima, Catalytic
asymmetric synthesis, Wiley-VCH, Weinheim, 2000; E. N. Jacobsen,
A. Pfaltz and H. Yamamoto, Comprehensive asymmetric catalysis.
Supplement, Springer, Berlin, New York, 2004.
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