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CDCl3): δ 7.42-7.17 (m, 13H), 7.04-7.00 (m, 2H), 5.88 (d, J = 1.1 Hz, 1H), 4.60 (d, J = 17.7 Hz,
1H), 4.18 (d, J = 13.7 Hz, 1H), 3.81 (s, 3H), 3.44 (d, J = 13.8 Hz, 1H), 3.10-2.98 (m, 2H), 1.36
(d, J = 7.5 Hz, 3H); 13 C NMR (75 MHz, CDCl3): δ 204.7, 171.8, 171.7, 153.6, 141.2, 136.6,
135.9, 135.5, 130.8, 130.3, 130.1, 128.9, 128.8, 128.7, 128.7, 128.6, 127.6, 126.8, 122.2, 66.6,
59.9, 53.3, 45.2, 42.9, 40.3, 13.9; IR (thin film): ν 2949, 1741, 1706, 1643 1259 cm -1 ; MS m/z
(%) 477 (6), 418 (63), 386 (55), 105 (100); EI-HRMS calcd for C31H27NO4 m/z [M] + 477.1940;
found 477.1954.
270d (minor diastereomer, Rt = 18 min HPLC, hexanes/EtOAc 5 : 1, v/v): 1 H NMR (300 MHz,
CDCl3): δ 7.40-7.20 (m, 13H), 7.03-6.99 (m, 2H), 5.90 (d, J = 0.9 Hz, 1H), 4.59 (d, J = 18.2, 1.2
Hz, 1H), 4.19 (d, J = 13.8 Hz, 1H), 3.83 (s, 3H), 3.45 (d, J = 13.8 Hz, 1H), 3.17 (d, J = 18.3 Hz,
1H), 3.03 (q, J = 7.5 Hz, 1H), 1.41 (d, J = 7.6 Hz, 3H); 13 C NMR (75 MHz, CDCl3): δ 204.9,
172.1, 171.7, 153.8, 140.7, 136.4, 136.0, 135.5, 130.9, 130.3, 130.1, 129.1, 128.8, 128.7, 128.6,
128.5, 127.6, 126.8, 122.5, 66.4, 53.3, 45.6, 42.6, 40.3, 14.9; IR (thin film): ν 2950, 1741, 1706,
1645, 1235 cm -1 ; MS m/z (%) 477 (10), 418 (15), 386 (25), 105 (100); EI-HRMS calcd for
C31H27NO4 m/z [M] + 477.1940; found 477.1941.
Bz
MeO 2C
TBSO
N
2-Benzoyl-3-(tert-butyldimethylsilyloxymethyl)-5,7-dimethyl-6-oxo-2,3,5,6-tetrahydro-1H-
270e
[2]pyrindine-3-carboxylic acid methyl ester (270e). Prepared by following general procedure
N, using: 73e (50 mg, 113 µmol), [Rh(CO)2Cl]2 (4 mg, 11 µmol), PPh3 (9 mg, 34 µmol), AgBF4
(250 µL of 0.1 M solution in DCE, 25 µmol). The reaction was heated at 35 °C for 1 h.
Yield 270e (43 mg, 81%) as a mixture of diastereomers in 1.7 : 1 ratio. The diastereomers were
separated by semi-preparative HPLC (hexanes-EtOAc, 6 : 1 v/v, flow rate 3 mL/min, UV
239
O