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G. Mehta, N. S. Likhite / Tetrahedron Letters 49 (2008) 7113–7116
39.95, 38.90, 37.93, 25.93, 25.89, 25.63, 24.95, 24.46, 21.98, 18.10, À3.85,
J = 9.2, 4.0 Hz, 1H), 5.08 (d, J = 11.2 Hz, 1H), 3.81 (s, 3H), 3.75 (s, 3H), 2.75 (t,
J = 12.0 Hz, 1H), 2.70–2.63 (m, 2H), 2.17–2.11 (m, 1H), 1.69–1.66 (m, 1H), 1.56–
1.51 (m, 1H), 1.50–1.46 (m, 2H), 1.25–1.19 (m, 2H), 1.10 (d, J = 6.6 Hz, 3H), 1.06
(s, 3H), 1.05 (s, 3H); 13C NMR (100 MHz, CDCl3) d 213.80, 153.64, 151.61,
150.56, 128.37, 116.55, 115.87, 111.49, 110.97, 55.99, 55.74, 50.59, 46.08,
44.02, 42.47, 38.46, 33.99, 30.29, 29.69, 25.95, 22.75, 17.88; HRMS (ES) m/z
calcd for C22H30O3 (M+Na+): 365.2093; found: 365.2086; Compound 2 1H NMR
(400 MHz, CDCl3) d 7.23 (d, J = 8.7 Hz, 1H), 7.12 (d, J = 2.4 Hz, 1H), 6.70 (dd,
J = 8.6, 2.5 Hz, 1H), 4.53 (br s, 1H, OH), 3.21–3.15 (m, 1H), 2.55 (t, J = 5.7 Hz,
2H), 2.17–2.06 (m, 3H), 1.72–1.69 (m, 2H), 1.62–1.55 (m, 3H), 1.34 (d,
J = 6.9 Hz, 3H), 1.09 (s, 3H), 1.08 (s, 3H); 13C NMR (100 MHz, CDCl3) d 160.23,
150.70, 149.10, 144.37, 129.62, 123.76, 116.46, 111.06, 110.88, 107.26, 39.52,
38.56, 35.70, 34.67, 30.52, 28.92, 27.88, 26.05, 20.02, 19.73.
À4.70; HRMS (ES) m/z calcd for C29H48O4Si (M+Na+): 511.3220; found:
511.3227; Compound 16 IR (neat) 3440, 1588, 1495, 1464 cmÀ1 1H NMR
;
(400 MHz, CDCl3) d 7.06 (d, J = 2.6 Hz, 1H), 6.78 (d, J = 8.8 Hz, 1H), 6.70 (dd,
J = 8.8, 2.9 Hz, 1H), 5.84–5.72 (m, 2H), 5.56 (br s, 1H), 4.01 (d, J = 5.7 Hz, 1H),
3.78 (s, 3H), 3.76 (s, 3H), 3.29 (d, J = 9.6 Hz, 1H), 2.56–2.45 (m, 3H), 1.49–1.39
(m, 3H), 1.29–1.21 (m, 6H), 1.22 (s, 3H), 1.00 (s, 3H), 0.89 (s, 9H), À0.09 (s, 3H),
À0.47 (s, 3H); 13C NMR (100 MHz, CDCl3) d 153.40, 151.31, 134.56, 131.07,
130.24, 116.25, 111.05, 110.13, 75.40, 72.94, 56.21, 55.66, 46.89, 43.90, 39.53,
37.46, 32.42, 30.55, 25.90 (3C), 25.86, 23.61, 20.97, 17.89, À4.12, À6.00; HRMS
(ES) m/z calcd for C27H44O4Si (M+Na+): 483.2907; found: 483.2910; Compound
17 IR (neat) 3534, 1590, 1496, 1462 cmÀ1 1H NMR (300 MHz, CDCl3) d 7.00 (d,
;
J = 3.0 Hz, 1H), 6.75 (d, J = 8.7 Hz, 1H), 6.68–6.64 (m, 1H), 6.16 (t, J = 8.5 Hz, 1H),
5.75 (dd, J = 14.8, 9.1 Hz, 1H), 4.00 (d, J = 6.6 Hz, 1H), 3.77 (s, 3H), 3.74 (s, 3H),
3.39 (d, J = 10.5 Hz, 1H), 3.06 (dd, J = 13.9, 5.5 Hz, 1H), 2.63 (dd, J = 16.0,
10.0 Hz, 1H), 2.39 (dd, J = 13.6, 8.5 Hz, 1H), 1.91 (br s, 1H), 1.72–1.63 (m, 1H),
1.42–1.23 (m, 3H), 1.14–1.01 (m, 2H), 1.02 (s, 6H), 0.88 (s, 9H), À0.13 (s, 3H),
À0.29 (s, 3H); 13C NMR (75 MHz, CDCl3) d 153.47, 151.24, 137.26, 135.31,
129.85, 116.25, 111.17, 109.78, 75.42, 72.44, 55.29, 55.68, 42.18, 40.05, 39.02,
37.39, 33.47, 29.69, 27.67, 25.92 (2C), 25.48, 22.80, 22.06, 18.06, À4.34, À5.53;
HRMS (ES) m/z calcd for C27H44O4Si (M+Na+): 483.2907; found: 483.2914;
13. Pinnick, H. W. Org. React. 1990, 38, 655–792.
14. X-ray data were collected at 291 K on a Bruker Kappa APEX II diffractometer
with graphite monochromated MoK
a radiation (k = 0.7107 Å). The crystal
structure was solved by direct methods (SIR92) and refined by full-matrix
least-squares method on F2 using SHELXL-97. Crystallographic data have been
deposited with the Cambridge Crystallographic Data Centre, CCDC 697873.
Compound 15: C29H48O4Si, MW = 488.33, crystal system: monoclinic, space
group: P21/n, cell parameters: a = 20.1001(7) Å, b = 7.2963(2) Å, c =
Compound 18 IR (neat) 2950, 1613, 1496 cmÀ1
;
1H NMR (400 MHz, CDCl3) d
22.5767(8) Å, b = 116.108(2)°, V = 2973.18(17) Å3, Z = 4, calc = 1.072 g cmÀ3
q ,
7.08 (d, J = 3.0 Hz, 1H), 6.74 (d, J = 8.4 Hz, 1H), 6.65 (dd, J = 8.7, 3.0 Hz, 1H),
5.95–5.83 (m, 2H), 5.82 (d, J = 5.2 Hz, 1H), 4.35 (t, J = 4.3 Hz, 1H), 3.81 (dd,
J = 10.1, 2.8 Hz, 1H), 3.77 (s, 3H), 3.72 (s, 3H), 2.92–2.86 (m, 1H), 1.54–1.38 (m,
6H), 1.19 (s, 3H), 1.13 (s, 3H), 0.82 (s, 9H), À0.02 (s, 3H), À0.06 (s, 3H); 13C NMR
(100 MHz, CDCl3) d 156.34, 153.48, 151.57, 136.28, 135.26, 126.37, 117.02,
114.47, 110.94, 110.90, 72.50, 56.13, 55.66, 50.23, 42.29, 41.87, 38.39, 33.75,
31.82, 27.83, 25.86, 25.48, 21.87, 18.18, À4.29, À4.91; HRMS (ES) m/z calcd for
C27H42O3Si (M+Na+): 465.2001; found: 465.2817; Compound 21 IR (neat) 2929,
F(000) = 1036,
for 3665 reflections with I > 2
l
= 0.107 mmÀ1, number of l.s. parameters = 324, R1 = 0.0678
(I) and 0.1062 for all 5501 data. wR2 = 0.2465,
r
GOF = 1.086 for all data. An ORTEP diagram of 15, drawn at 30% ellipsoidal
probability, is shown below.
1708, 1497, 1221 cmÀ1 1H NMR (300 MHz, CDCl3) d 6.84–6.73 (m,3H), 6.25 (d,
;
J = 10.5 Hz, 1H), 5.50–5.43 (m, 1H), 4.42 (s, 1H), 3.74 (s, 3H), 3.72 (s, 3H), 3.10
(d, J = 5.4 Hz, 1H), 2.08 (t, J = 6.1 Hz, 1H), 1.63–1.47 (m, 6H), 1.17 (s, 3H), 1.05 (s,
3H); 13C NMR (75 MHz, CDCl3)
d 203.12, 153.43, 152.11, 140.33, 130.66,
129.46, 126.27, 122.11, 114.80, 112.58, 111.64, 60.06, 56.06, 55.52, 43.82,
38.61, 34.38, 31.94, 29.02, 28.44, 19.43; HRMS (ES) m/z calcd for C21H26O3
(M+Na+): 349.1780; found: 349.1767; Compound 6 IR (neat) 2925, 1715, 1497,
1049 cmÀ1 1H NMR (300 MHz, CDCl3) d 6.83 (d, J = 9.0 Hz, 1H), 6.79–6.75 (m,
;
1H), 6.66 (d, J = 3.0 Hz, 1H), 4.23 (s, 1H), 3.75 (s, 3H), 3.73 (s, 3H), 2.70–2.61 (m,
1H), 2.46–2.36 (m, 1H), 2.21–2.04 (m, 4H), 1.96–1.68 (m, 2H), 1.64–1.50 (m,
4H), 1.11 (s, 3H), 1.08 (s, 3H); 13C NMR (75 MHz, CDCl3) d 210.31, 153.72,
152.46, 141.48, 129.24, 127.20, 114.14, 112.43, 111.66, 61.06, 56.13, 55.48,
39.97, 39.21, 35.74, 32.44, 28.19, 27.82, 26.78, 26.22, 19.80; HRMS (ES) m/z
calcd for C21H28O3 (M+Na+): 351.1936; found: 351.1920; Compound 24 IR
(neat) 2926, 1716, 1497, 1463 cmÀ1 1H NMR (500 MHz, CDCl3) d 7.05 (d,
;
J = 3.0 Hz, 1H), 6.78–6.73 (m, 2H), 5.64 (dd, J = 8.8, 4.9 Hz, 1H), 4.93 (d,
J = 10.8 Hz, 1H), 3.80 (s, 3H), 3.74 (s, 3H), 2.94–2.87 (m, 1H), 2.79 (t, J = 11.3 Hz,
1H), 2.70–2.65 (m, 1H), 2.61–2.55 (m, 1H), 2.22–2.15 (m, 1H), 1.78–1.75 (m,
1H), 1.62–1.48 (m, 3H), 1.28–1.16 (m, 2H), 1.08 (s, 3H), 1.06 (s, 3H); 13C NMR
(100 MHz, CDCl3) d 211.09, 153.57, 151.63, 150.38, 128.51, 117.42, 115.51,
111.26, 110.91, 56.07, 55.68, 49.62, 45.27, 42.42, 42.36, 38.51, 34.13, 30.36,
25.99, 22.69, 20.88; HRMS (ES) m/z calcd for C21H28O3 (M+Na+): 351.1936;
found: 351.1926; Compound 25 IR (neat) 2926, 1716, 1498, 1216 cmÀ1
;
1H
NMR (400 MHz, CDCl3) d 7.13 (d, J = 2.4 Hz, 1H), 6.78–6.73 (m, 2H), 5.59 (dd,