C. Müller, C. Loos, N. Schulenberg, S. Doye
SHORT COMMUNICATION
recorded with a JEOL JMS-700 or a Finnigan TSQ 700 (EI) spec-
trometer with an ionization potential of 70 eV. Elemental analyses
were carried out with an Elementar Vario EL machine. GC-MS
analyses were performed with a Hewlett–Packard HP 5890 Series
II gas chromatograph equipped with a Hewlett Packard HP 5972
Series I Mass Selective Detector. PE: light petroleum ether, b.p. 40–
60 °C.
amino-2,2-dimethyl-4-pentene (15) (272 mg, 2.40 mmol), the pre-
catalyst (0.12 mmol, 5 mol-%, Table 3), and toluene (2.0 mL).
Then, the tube was sealed and the resulting mixture was heated to
105 °C for the appropriate time (Table 3). After the mixture had
been cooled to room temperature, CH2Cl2 (5.0 mL), benzoyl chlo-
ride (0.3 mL, 2.64 mmol), and NEt3 (1.0 mL, 7.2 mmol) were
added. The resulting mixture was stirred at 25 °C for 12 h. Then,
the solution was diluted with Et2O (30 mL), washed with saturated
NH4Cl solution, and dried with MgSO4. After concentration under
vacuum in the presence of celite®, the product 16 was isolated as a
colorless oil by flash chromatography (SiO2, PE/EtOAc, 10:1). For
reactions performed with Cp2TiMe2 (3) as the pre-catalyst, only
the amine was added to the Schlenk tube inside of the glovebox.
Then, the Schlenk tube was removed from the glovebox and
Cp2TiMe2 (0.26 mL, c = 0.46 mol/L in toluene, 0.12 mmol, 5 mol-
%) and toluene (1.7 mL) were added. 1H NMR (500 MHz, CDCl3):
δ = 0.90 (s, 3 H), 1.04 (s, 3 H), 1.31–1.47 (m, 4 H), 1.93 (dd, J =
11.9, 7.5 Hz, 1 H), 3.10 (d, J = 10.4 Hz, 1 H), 3.29 (d, J = 10.4 Hz,
1 H), 4.30–4.42 (m, 1 H), 7.34–7.42 (m, 3 H), 7.52 (d, J = 6.0 Hz,
2 H) ppm. 13C NMR (125 MHz, DEPT, CDCl3): δ = 20.1 (CH3),
25.3 (CH3), 25.6 (CH3), 38.1 (C), 47.4 (CH2), 52.8 (CH), 62.5
(CH2), 127.4 (CH), 128.0 (CH), 129.8 (CH), 137.2 (C), 170.0 (C)
2-Methyl-4,4-diphenylpyrrolidine (10): A flame-dried Schlenk tube
equipped with a Teflon stopcock and a magnetic stirring bar was
transferred into a nitrogen-filled glovebox and charged with 1-
amino-2,2-diphenyl-4-pentene (9) (570 mg, 2.40 mmol), the pre-cat-
alyst (0.12 mmol, 5 mol-%, Table 1), and toluene (2.0 mL). Then,
the tube was sealed, and the resulting mixture was heated to 105 °C
for the appropriate time (Table 1). After the mixture had been co-
oled to room temperature, the product 10 was isolated as a colorless
oil by flash chromatography (SiO2, PE/EtOAc, 1:2). For reactions
performed with Cp2TiMe2 (3) as the pre-catalyst, only the amine
was added to the Schlenk tube inside of the glovebox. Then, the
Schlenk tube was removed from the glovebox and Cp2TiMe2
(0.26 mL, c = 0.46 mol/L in toluene, 0.12 mmol, 5 mol-%) and tolu-
1
ene (1.7 mL) were added. H NMR (500 MHz, CDCl3): δ = 1.18
(d, J = 6.4 Hz, 3 H), 1.98–2.04 (m, 2 H), 2.70 (dd, J = 12.4, 6.4 Hz,
1 H), 3.30–3.38 (m, 1 H), 3.45 (d, J = 11.4 Hz, 1 H), 3.64 (d, J =
11.4 Hz, 1 H), 7.10–7.14 (m, 2 H), 7.19–7.29 (m, 8 H) ppm. 13C
NMR (125 MHz, DEPT, CDCl3): δ = 22.2 (CH3), 46.9 (CH2), 52.9
(CH), 57.1 (C), 57.7 (CH2), 125.7 (CH), 125.8 (CH), 126.8 (CH),
126.8 (CH), 128.1 (CH), 128.1 (CH), 146.9 (C), 147.6 (C) ppm. IR
ppm. IR (neat): ν = 3059, 3029, 2958, 2928, 2868, 1629, 1603, 1578,
˜
1496, 1465, 1447, 1409, 1372, 1352, 1321, 1290, 1213, 1137, 794,
719, 699 cm–1. MS (25 °C): m/z (%) = MS (25 °C): m/z (%) = 218
(1) [M+H+], 217 (4) [M+], 202 (4), 160 (4), 105 (77), 77 (100), 56
(26), 55 (19), 51 (37), 41 (30), 39 (17). C14H19NO (217.3): calcd. C
77.38, H 8.81, N 6.45; found C 77.07, H 8.67, N 6.49.
(neat): ν = 3084, 3057, 3025, 2958, 2920, 2968, 1598, 1493, 1446,
˜
1372, 1129, 1098, 1032, 906, 869, 773, 756, 700 cm–1. MS (25 °C):
m/z (%) = 238 (27) [M+H+], 237 (73) [M+], 222 (8) [M+ – CH3], Acknowledgments
193 (12), 178 (23), 165 (20), 115 (16), 91 (10), 77 (4), 57 (100).
We thank the Deutsche Forschungsgemeinschaft, the Fonds der
Chemischen Industrie and the Dr. Otto Röhm Gedächtnisstiftung,
C17H19N (237.3): calcd. C 86.03, H 8.07, N 5.90; found C 85.78,
H 8.14, N 5.93.
Darmstadt, for financial support of our research.
2-Methyl-5,5-diphenylpiperidine (12): A flame-dried Schlenk tube
equipped with a Teflon stopcock and a magnetic stirring bar was
transferred into a nitrogen-filled glovebox and charged with 1-
amino-2,2-diphenyl-5-hexene (11) (603 mg, 2.40 mmol), the pre-
catalyst (0.12 mmol, 5 mol-%, Table 2), and toluene (2.0 mL).
Then, the tube was sealed, and the resulting mixture was heated
to 105 °C for 24 h. After the mixture had been cooled to room
temperature, the product 12 was isolated as a colorless oil by flash
chromatography (SiO2, PE/EtOAc, 1:2). For reactions performed
with Cp2TiMe2 (3) as the pre-catalyst, only the amine was added
to the Schlenk tube inside of the glovebox. Then, the Schlenk tube
was removed from the glovebox and Cp2TiMe2 (0.26 mL, c =
0.46 mol/L in toluene, 0.12 mmol, 5 mol-%) and toluene (1.7 mL)
were added. 1H NMR (500 MHz, CDCl3): δ = 1.00 (d, J = 6.4 Hz,
3 H), 1.10–1.20 (m, 1 H), 1.29 (br. s, 1 H), 1.60–1.65 (m, 1 H), 2.21
(dt, J = 3.7, 13.4 Hz, 1 H), 2.67–2.81 (m, 2 H), 3.10 (d, J = 13.7 Hz,
1 H), 3.91 (dd, J = 13.7, 3.0 Hz, 1 H), 7.08–7.43 (m, 10 H) ppm.
13C NMR (125 MHz, DEPT, CDCl3): δ = 22.5 (CH3), 31.4 (CH2),
35.4 (CH2), 45.2 (C), 52.3 (CH), 55.8 (CH2), 125.7 (CH), 125.7
(CH), 126.4 (CH), 128.1 (CH), 128.2 (CH), 128.6 (CH), 144.8 (C),
[1] For reviews, see: a) T. E. Müller, M. Beller, Chem. Rev. 1998,
98, 675–703; b) J. J. Brunet, D. Neibecker, in Catalytic Hetero-
functionalization (Eds.: A. Togni, H. Grützmacher), Wiley-
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Angew. Chem. 2003, 115, 2812–2815; Angew. Chem. Int. Ed.
2003, 42, 2708–2710; d) K. C. Hultzsch, Adv. Synth. Catal.
2005, 347, 367–391; e) K. C. Hultzsch, Org. Biomol. Chem.
2005, 3, 1819–1824.
[2] For recent examples of hydroamination catalyzed by lantha-
nide complexes, see: a) D. V. Gribkov, K. C. Hultzsch, F. Ham-
pel, Chem. Eur. J. 2003, 9, 4796–4810; b) A. Zulys, T. K. Panda,
M. T. Gamer, P. W. Roesky, Chem. Commun. 2004, 2584–2585;
c) S. Hong, T. J. Marks, Acc. Chem. Res. 2004, 37, 673–686; d)
J.-S. Ryu, T. J. Marks, J. Org. Chem. 2004, 69, 1038–1052; e) S.
Tobisch, J. Am. Chem. Soc. 2005, 127, 11979–11988.
[3] For recent examples of hydroamination catalyzed by late tran-
sition metal complexes, see: a) C. F. Bender, R. A. Widenho-
efer, J. Am. Chem. Soc. 2005, 127, 1070–1071; b) J. Takaya,
J. F. Hartwig, J. Am. Chem. Soc. 2005, 127, 5756–5757; c) D.
Karshtedt, A. T. Bell, T. D. Tilley, J. Am. Chem. Soc. 2005, 127,
12640–12646; d) J.-J. Brunet, N. C. Chu, O. Diallo, Organome-
tallics 2005, 24, 3104–3110; e) A. Zulys, M. Dochnahl, D.
Hollmann, K. Löhnwitz, J.-S. Herrmann, P. W. Roesky, S. Ble-
chert, Angew. Chem. 2005, 117, 7972–7976; Angew. Chem. Int.
Ed. 2005, 44, 7794–7798.
[4] For recent examples of hydroamination catalyzed by group-III
metal complexes, see: a) Y. K. Kim, T. Livinghouse, J. E.
Bercaw, Tetrahedron Lett. 2001, 42, 2933–2935; b) J. Y. Kim, T.
Livinghouse, Angew. Chem. 2002, 114, 3797–3799; Angew.
Chem. Int. Ed. 2002, 41, 3645–3647; c) F. Lauterwasser, P. G.
Hayes, S. Bräse, W. E. Piers, L. L. Schafer, Organometallics
148.8 (C) ppm. IR (neat): ν = 3086, 3057, 3027, 2931, 2864, 2797,
˜
1599, 1494, 1462, 1445, 1376, 1156, 1130, 1107, 925, 844, 751,
699 cm–1. MS (25 °C): m/z (%) = 252 (5) [M+H+], 251 (10) [M+],
236 (5) [M+ – CH3], 193 (3), 179 (32), 165 (40), 115 (7), 91 (9), 71
(7), 58 (100). C18H21N (251.4): calcd. C 86.01, H 8.42, N 5.57;
found C 85.78, H 8.44, N 5.84.
N-Benzoyl-2,4,4-trimethylpyrrolidine (16): A flame-dried Schlenk
tube equipped with a Teflon stopcock and a magnetic stirring bar
was transferred into a nitrogen-filled glovebox and charged with 1-
2502
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