2428
S. Barroso et al.
LETTER
from a MeOH solution at –20 °C. Anal. Calcd for
Macromolecules 2009, 42, 4008.
(4) (a) Burke, W. J.; Weatherbee, C.; Lau, H.; Van Lear, G.;
Goken, G. J. Am. Chem. Soc. 1964, 29, 909. (b) Moloney,
G. P.; Craik, D. J.; Iskander, M. N. J. Pharm. Sci. 1992, 81,
692. (c) Colin, J. L.; Loubinoux, B. Tetrahedron Lett. 1982,
23, 4245.
(5) (a) Woodgate, P. D.; Horner, G. M.; Maynard, N. P.;
Rickard, C. E. F. J. Organomet. Chem. 1999, 592, 180.
(b) Lyle, R. E.; Walsh, D. A. J. Organomet. Chem. 1974, 67,
363. (c) Chirachanchai, S.; Laobuthee, A.; Phongtamburg,
S.; Siripatanasarakit, W.; Ishida, H. J. Appl. Polym. Sci.
2000, 77, 2561.
C32H42N2O·C14H22O: C, 81.65; H, 9.29; N, 4.23. Found: C,
81.47; H, 10.11; N, 4.17.
(12) Supplementary crystallographic data for 7e and 10e may be
obtained from the Cambridge Crystallographic Data Centre
data_request@ccdc.cam.ac.uk) under the deposit numbers
CCDC 773865 and CCDC 773866, respectively.
(13) Higham, C. S.; Dowling, D. P.; Shaw, J. L.; Cetin, A.;
Ziegler, C. J.; Farrell, J. R. Tetrahedron Lett. 2006, 47, 4419;
and references cited therein.
(14) Compound 8a: 1H NMR (300 MHz, CDCl3): d = 7.57 (d,
JHH = 8.3 Hz, 2 H, Ar), 7.50 (d, JHH = 8.1 Hz, 2 H, Ar), 7.22
(d, JHH = 1.9 Hz, 1 H, Ar), 6.69 (d, JHH = 1.8 Hz, 1 H, Ar),
4.94 (s, 1 H, ArCHPhN), 2.75 (m, 2 H, CH2), 2.59 (m, 2 H,
CH2), 2.42 (m, 1 H, CH2), 2.21 [s, 6 H, N(CH3)2] 1.44 [s, 9
H, C(CH3)3], 1.21 [s, 9 H, C(CH3)3] ppm. 13C-{1H} NMR
(75 MHz, CDCl3): d = 154.4, 146.3, 140.7, 136.7 (Cipso),
129.6 (Ar), 128,1 (2 C, Ar), 125.9 (2 C, Ar), 123.7, 123.4
(Ar), 68.3 (ArCHPhN), 58.4 (CH2), 45.5 [N(CH3)2], 45.2
(CH2), 35.2, 34.3 [C(CH3)3], 31.8, 29.8 [C(CH3)3] ppm. In
this case, small amounts of the corresponding benzoxazine
were also detected.
(6) Barroso, S.; Cui, J.; Carretas, J. M.; Cruz, A.; Santos, I. C.;
Duarte, M. T.; Telo, J. P.; Marques, N.; Martins, A. M.
Organometallics 2009, 28, 3449.
(7) Tshuva, E. Y.; Versano, M.; Goldberg, I.; Kol, M.; Weitman,
M.; Goldschmidt, Z. Inorg. Chem. Commun. 1999, 2, 371.
(8) Compound 7a: 1H NMR (300 MHz, CDCl3): d = 7.20 (m, 5
H, Ar), 7.07 (d, JHH = 2.08 Hz, 1 H, Ar), 6.67 (d, JHH = 2.21
Hz, 1 H, Ar), 4.71 (s, 2 H, NCH2O), 3.90 (s, 2 H, ArCH2N),
3.80 (s, 2 H, CH2Ph), 1.30 [s, 9 H, C(CH3)3], 1.70 [s, 9 H,
C(CH3)3] ppm. 13C-{1H} NMR (75 MHz , CDCl3): d =
150.7, 142.2, 138.5, 136.7 (Cipso), 129.2 (2 C, Ar), 128.6 (2
C, Ar), 127.4 (Ar), 122.2 (2 C, Ar), 119.0 (Cipso), 81.0
(NCH2O), 55.8 (CH2Ph), 51.1 (ArCH2N), 35.0, 34.4
(C(CH3)3), 31.7, 29.8 (C(CH3)3) ppm. Anal. Calcd for
C23H31NO: C, 81.85; H, 9.26; N, 4.15. Found: C, 82.12; H,
10.22; N, 3.84.
Compound 8b: 1H NMR (300 MHz, CDCl3): d = 7.45 (d,
JHH = 8.4 Hz, 2 H, Ar), 7.26 (d, JHH = 8.4 Hz, 2 H, Ar), 7.21
(d, JHH = 2.3 Hz, 1 H, Ar), 6.66 (d, JHH = 2.2 Hz, 1 H, Ar),
4.86 (s, 1 H, ArCHPhN), 2.72 (m, 2 H, CH2), 2.58 (m, 1 H,
CH2), 2.36 (m, 1 H, CH2), 2.19 [s, 6 H, N(CH3)2], 1.45 [s, 9
H, C(CH3)3], 1.21 [s, 9 H, C(CH3)3] ppm. 13C-{1H} NMR
(75 MHz, CDCl3): d = 154.4, 141.3, 140.5, 136.5 (Cipso),
132.0 (2 C, Ar), 129,6 (2 C, Ar), 123.8 (Cipso), 132.0, 129.5
(Ar), 121.6 (Cipso), 67.9 (ArCHPhN), 58.4 (CH2), 45.5
[N(CH3)2], 45.1 (CH2), 35.2, 34.3 [C(CH3)3], 31.8, 29.8
[C(CH3)3] ppm.
(9) Compound 7d: 1H NMR (300 MHz, CDCl3): d = 7.78 (s, 1
H, Ar), 7.75 (s, 1 H, Ar), 7.37 (m, 14 H, Ar), 6.93 (d,
JHH = 2.23 Hz, 1 H, Ar), 5.92 (s, 1 H, OCHPhN), 4.98 (s, 1
H, ArCHPhN), 3.94 (d, JHH = 13.95 Hz, 1 H, CH2Ph), 3.49
(d, JHH = 13.96 Hz, 1 H, CH2Ph), 1.66 [s, 9 H, C(CH3)3],
1.37 [s, 9 H, C(CH3)3] ppm. 13C-{1H} NMR (75 MHz,
CDCl3): d = 151.1, 144.5, 141.9, 139.5, 138.9, 136.8 (Cipso),
129.2 (2 C, Ar), 129.1 (2 C, Ar), 128.3 (2 C, Ar), 128.2 (2 C,
Ar), 128.0 (2 C, Ar), 127.7, 127.0, 126.9 (Ar), 126.6 (2 C,
Ar), 125.2, 122.5 (Ar), 118.5 (Cipso), 85.7 (ArCHPhN), 60.8
(NCHPhO), 49.4 (CH2Ph), 35.1, 34.3 [C(CH3)3], 31.6, 29.9
[C(CH3)3] ppm. Anal. Calcd for C35H39NO: C, 85.84; H,
8.03; N, 2.86. Found: C, 84.87; H, 8.51; N, 3.56.
(15) Bürgi, H. B.; Dunitz, J. D.; Shefter, E. J. Am. Chem. Soc.
1973, 95, 5065.
(16) Compound 10a: 1H NMR (300 MHz, CDCl3): d = 7.49 (m,
2 H, Ar), 7.37 (m, 3 H, Ar), 7.31 (d, JHH = 2.20 Hz, 1 H, Ar),
6.96 (d, JHH = 2.15 Hz, 1 H, Ar), 3.92 (s, 2 H, ArCH2N), 3.86
(s, 2 H, CH2Ph), 1.38 [s, 9 H, C(CH3)3], 1.23 [s, 9 H,
C(CH3)3] ppm. 13C-{1H} NMR (75 MHz, CDCl3): d = 151.3,
144.4, 141.4 (Cipso), 130.1 (2 C, Ar), 130.0 (Cipso), 129.4
(Ar), 129.1 (2 C, Ar), 126.9, 125.7 (Ar), 121.3 (Cipso), 49.4
(ArCH2N), 46.5 (CH2Ph), 35.1, 34.3 [C(CH3)3], 31.4, 30.1
[C(CH3)3] ppm. Anal. Calcd for C22H31NO·2.12 (CH3OH):
C, 73.37; H, 10.13; N, 3.53. Found: C, 73.33; H, 9.80; N,
3.66.
(10) For isolated examples, see: (a) Morimura, S. Heterocycles
1980, 1331. (b) Neuvonen, K.; Pihlaja, K. Acta Chem.
Scand. 1993, 47, 695. (c) For a discussion of how steric
hindrance around the phenol OH affects benzoxazine
formation, see ref. 4a.
(11) Compound 7e: 1H NMR (300 MHz, CDCl3): d = 7.68 (d,
JHH = 7.41 Hz, 2 H, Ar), 7.56 (d, JHH = 7.48 Hz, 2 H, Ar),
7.45 (m, 5 H, Ar), 7.73 (m, 2 H, Ar), 7.07 (d, JHH = 2.23 Hz,
1 H, Ar), 5.78 (s, 1 H, NCHPhO), 5.20 (s, 1 H, ArCHPhN),
3.01 (m, 1 H, CH2), 2.84 (m, 1 H, CH2), 2.72 (m, 1 H, CH2),
2.55 (m, 1 H, CH2), 2.24 [s, 6 H, N(CH3)2] 1.66 [s, 9 H,
C(CH3)3], 1.44 [s, 9 H, C(CH3)3] ppm. 13C-{1H} NMR
(75 MHz, CDCl3): d = 152.8, 144.6, 138.7, 137.0, 135.4
(Cipso), 129.1 (2 C, Ar), 128.0 (4 C, Ar), 126.5 (2 C, Ar),
125.0, 123.8, 122.5 (Ar), 118.9 (Cipso), 85.7 (NCHPhO), 63.2
(ArCHPhN), 59.1 (CH2), 45.4 [N(CH3)2], 43.2 (CH2), 35.1,
34.8 [C(CH3)3], 31.6, 29.9 [C(CH3)3] ppm. Colourless
crystals of 7e suitable for X-ray diffraction were obtained
Compound 10b: 1H NMR (300 MHz, CDCl3): d = 7.27 (s, 1
H, Ar), 7.07 (s, 1 H, Ar), 3.97 (s, 2 H, ArCH2N), 2.69 (m, 1
H, CH, Cy), 1.97 (m, 2 H, CH2, Cy), 1.73 (m, 2 H, CH2, Cy),
1.62 (m, 1 H, CH2, Cy), 1.42 [s, 9 H, C(CH3)3], 1.29 [s, 9 H,
C(CH3)3], 1.19 (m, 5 H, CH2, Cy) ppm. 13C-{1H} NMR
(75 MHz, CDCl3): d = 152.7, 142.8, 129.0 (Cipso), 125.9,
124,3 (Ar), 121.6 (Cipso), 56.9 (CH, Cy), 47.1 (ArCH2N),
35.2, 34.4 [C(CH3)3], 31.5, 30.1 [C(CH3)3], 29.8 (2 C, CH2,
Cy), 25.3 (CH2, Cy), 24.9 (2 C, CH2, Cy) ppm. Anal. Calcd
for C21H35NO·2.64 (CH3OH): C, 70.62; H, 11.42; N, 3.48.
Found: C, 70.54; H, 10.50; N, 3.96.
Synlett 2010, No. 16, 2425–2428 © Thieme Stuttgart · New York