N. Rozentul et al.
(75.49 MHz, CDCl3): δ = 25.06, 25.11, 29.82, 41.37, 57.12,
76.69, 117.06, 121.93, 126.02, 127.19, 127.82, 128.58, 129.05,
132.37, 142.60, 156.06 ppm; MS (EI) m/z: 329 [M + H].
6-(1,3-dithiolan-2-yl)-2-phenylchroman (6):
J = 6 Hz, 2H), 4.96 (d, J = 14.4 Hz, 1H), 5.17 (d,
J = 14.4 Hz, 1H), 6.01 (s, 1H), 6.78 (s, 1H), 7.03 (s, 1H),
7.42 (m, 3H), 7.51 ppm (m, 2H); 13C NMR (75.49 MHz,
CDCl3): δ = 20.66, 61.10, 66.73, 99.0, 124.58, 126.30,
127.89, 128.51, 129.47 ppm; MS (CI) m/z: 256 [M].
General Procedure for the Preparation of (11) (52).
The 10 (300 mg, 1.17 mmol) and PCC (378 mg,
1.75 mmol) in DCM (50 ml) were stirred at r. t. for 2 h.
After the reaction, the mixture was purified by column chro-
matography (silica gel, DCM) to give pure compound 11.
6-methyl-2-phenyl-4H-benzo[d] [1, 3]dioxin-8-
carbaldehyde (11):
The title compound was obtained starting from 4 (colorless
1
oil, 16%): H NMR (300 MHz, CDCl3): δ = 2.17 (m, 2H),
2.85 (m, 2H), 3.43 (m 4H), 5.04 (q, J = 2.7 Hz, 1H), 5.61 (s,
1H), 6.85 (d, J = 8 Hz, 1H), 7.34 ppm (m, 7H); 13C NMR
(75.49 MHz, CDCl3): δ = 25.11, 29.86, 40.28, 56.27, 77.93,
117.05, 121.82, 126.02, 127.19, 127.92, 128.59, 129.06,
131.37, 141.60, 155.05 ppm; MS (EI) m/z: 314 [M].
6-(1,3-dithiepan-2-yl)-2-phenylchroman (7):
The title compound was obtained starting from 4 (white
solid, 13%): 1H NMR (300 MHz, CDCl3): δ = 2.12 (m, 6H),
2.98 (m, 6H), 5.03 (d, J = 2.6 Hz, 1H), 5.26 (s, 1H), 6.84 (d,
J = 8 Hz, 1H), 7.30 ppm (m, 7H); 13C NMR (75.49 MHz,
CDCl3): δ = 25.11, 29.86, 31.71, 32.71, 56.67, 77.90, 117.11,
121.93, 126.01, 126.62, 127.89, 128.49, 128.56, 132.47,
141.63, 154.91 ppm; MS (EI) m/z: 342 [M].
The title compound was obtained starting from 10 (white
solid, 94%): H NMR (300 MHz, CDCl3): δ = 2.32 (s, 3H),
1
5.00 (d, J = 15 Hz, 1H), 5.20 (d, J = 15 Hz, 1H), 6.09 (s, 1H),
7.07 (m, 1H), 7.45 (m, 3H), 7.59 (m, 3H), 10.44 ppm (s, 1H);
13C NMR (75.49 MHz, CDCl3): δ = 20.51, 66.56, 99.39,
121.57, 123.99, 126.33, 126.95, 128.60, 129.69, 130.67,
131.72, 136.45 ppm; MS (ESI) m/z: 277 [M + Na].
8-(1,3-dithian-2-yl)-6-methyl-2-phenyl-4H-benzo[d] [1,
3]dioxin (12):
The title compound was obtained starting from 11 (white
solid, 25%): 1H NMR (300 MHz, CDCl3): δ = 2.03 (m, 2H),
2.28 (s, 3H), 2.98 (m, 4H), 4.92 (d, J = 14.4 Hz, 1H), 5.12 (d,
J = 14.4 Hz, 1H), 5.59 (s, 1H), 6.00 (s, 1H), 6.75 (s, 1H), 7.31 (s,
1H), 7.44 (m, 3H), 7.65 ppm (m, 2H); 13C NMR (75.49 MHz,
CDCl3): δ = 20.64, 25.36, 32.24, 32.32, 43.05, 66.49, 99.16,
120.61, 125.34, 126.60, 126.70, 128.20, 128.44, 129.34,
130.91, 137.23, 146.98 ppm; MS (CI) m/z: 345 [M + H].
8-(1,3-dithiepan-2-yl)-6-methyl-2-phenyl-4H-benzo[d] [1,
3]dioxin (13):
The title compound was obtained starting from 11 (white
solid, 11%): 1H NMR (300 MHz, CDCl3): δ = 2.09 (m, 4H),
2.28 (s, 4H), 2.85 (m, 2H), 3.12 (m, 2H), 4.93 (d, J = 14.4 Hz,
1H), 5.13 (d, J = 14.4 Hz, 1H), 5.70 (s, 1H), 6.01 (s, 1H), 6.73
(s, 1H), 7.33 (s, 1H), 7.44 (m, 3H), 7.62 ppm (m, 2H); 13C
NMR (75.49 MHz, CDCl3): δ = 19.70, 30.61, 30.67, 31.56,
47.52, 65.48, 97.96, 123.81, 125.43, 126.61, 127.36,
128.22 ppm; MS (EI) m/z: 358 [M].
6-(bis(ethylthio)methyl)-2-phenylchroman (8):
The title compound was obtained starting from 4 (colorless
1
oil, 8%): H NMR (300 MHz, CDCl3): δ = 1.23 (t, J = 7.5,
6H), 2.15 (m, 2H), 2.51 (m, 4H), 2.85 (m, 2H), 4.88p (s, 1H),
5.04p (q, J = 2.6 Hz, 1H), 6.85 (d, J = 9 Hz, 1H), 7.16 (m, 2H),
7.35 ppm (m, 5H); 13C NMR (75.49 MHz, CDCl3):
δ = 14.40, 25.21, 26.36, 29.93, 52.07, 77.94, 116.90,
121.91, 126.03, 126.86, 127.92, 128.58, 128.69, 132.18,
141.64, 154.79 ppm; MS (CI) m/z: 344 [M].
6-(bis(propylthio)methyl)-2-phenylchroman (9):
The title compound was obtained starting from 4 (yellow oil,
9%): 1H NMR (300 MHz, CDCl3): δ = 0.97 (t, J = 7.4 Hz, 6H),
1.59 (m, 4H), 2.13 (m, 2H), 2.52 (m, 4H), 2.78 (m, 1H), 2.98 (m,
1H), 4.82 (s, 1H), 5.04 (q, J = 2.4 Hz, 1H), 6.85 (d, J = 9 Hz,
1H), 7.18 (m, 2H), 7.36 ppm (m, 5H); 13C NMR (75.49 MHz,
CDCl3): δ = 13.63, 22.66, 25.20, 29.92, 34.45, 52.77, 77.93,
116.86, 121.88, 126.03, 126.85, 127.91, 128.57, 128.67,
132.35, 141.65, 154.76 ppm; MS (CI) m/z: 297 [M-PrS].
General Procedure for the Preparation of (10) (45).
2, 6-bis (hydroxymethyl)-4-methylphenol (1 g, 5.94 mmol)
was dried by three washes with toluene and evaporation. It
was then dissolved in 10 mL of dry DMF to which 1.4 mL of
BDA, 0.5 g of molecular sieve 3 Å, and 100 μL of dry hydro-
chloric acid 4 M (in dioxane) were added. The reaction mix
was left stirring for 12 h followed by neutralization with 15%
(w/v) sodium bicarbonate. The mixture was then filtered, and
the filtrate was washed with chloroform, dried over MgSO4,
and evaporated. The residue amorphic solids were purified by
HPLC, using a stepwise gradient of water and acetonitrile.
(6-methyl-2-phenyl-4H-benzo[d] [1, 3]dioxin-8-
yl)methanol (10):
8-(1,3-dithiolan-2-yl)-6-methyl-2-phenyl-4H-benzo[d] [1,
3]dioxin (14):
The title compound was obtained starting from 11 (white
1
solid, 23%): H NMR (300 MHz, CDCl3): δ = 2.29 (s, 3H),
3.38 (m, 4H), 4.94 (d, J = 14.4 Hz, 1H), 5.15 (d, J = 14.4 Hz,
1H), 6.01 (s, 1H), 6.74 (s, 1H), 7.43 (m, 4H), 7.63 ppm (m,
2H); 13C NMR (75.49 MHz, CDCl3): δ = 20.91, 39.54,
39.63, 48.37, 66.65, 99.04, 120.49, 124.75, 126.45, 127.25,
128.47, 128.74, 129.37, 130.51, 137.11 ppm; MS (EI) m/z:
330 [M].
8-(bis(ethylthio)methyl)-6-methyl-2-phenyl-4H-benzo[d]
[1, 3]dioxin (15):
The title compound was obtained starting from 2, 6-bis
1
(hydroxymethyl)-4-methylphenol (white solid, 35%): H
The title compound was obtained starting from 11 (white
NMR (300 MHz, CDCl3): δ = 2.29 (s, 3H), 4.68 (d,
solid, 26%): 1H NMR (300 MHz, CDCl3): δ = 1.22 (m, 6H),