“Extended” Biphenols Bridged by ortho-, meta-, and para-Phenylene Spacers
3
3
1
and 6Ј-H), 7.48 (t, JH,H = 7.6 Hz, 1 H, 5Ј-H), 7.34 (dd, JH,H
=
M.p. 119–120 °C. H NMR (500 MHz, C2D2Cl4, 410 K): δ = 7.51
4
3
3
4
7.6 Hz, JH,H = 1.6 Hz, 2 H, 4,4ЈЈ-H), 7.24 (dd, JH,H = 7.6 Hz, (2d, 4 H, 3Ј,6Ј-H and 4Ј,5Ј-H), 7.14 (dd, JH,H = 7.6 Hz, JH,H
=
4JH,H = 1.6 Hz, 2 H, 6,6ЈЈ-H), 7.15 (t, JH,H = 7.6 Hz, 2 H, 5,5ЈЈ), 1.2 Hz, 2 H, 4,4ЈЈ-H or 6,6ЈЈ-H), 7.06 (br. d, JH,H = 7.6 Hz, 2 H,
3
3
3.36 (s, 6 H, OCH3), 1.45 (s, 18 H, tBu-H) ppm. 13C NMR
6,6ЈЈ-H or 4,4ЈЈ-H), 6.90 (t, JH,H = 7.6 Hz, 2 H, 5,5ЈЈ-H), 3.27 (s,
3
(125 MHz, CDCl3): δ = 157.7, 143.2, 140.3, 135.4, 130.0, 129.8, 6 H, OCH3), 1.24 (s, 18 H, tBu-H) ppm. Data for 16-anti: 1H NMR
128.7, 127.8, 126.4, 123.3, 60.5, 35.3, 31.0 ppm. C28H34O2 (500 MHz, C2D2Cl4, 275 K): δ = 7.47 (AB of AAЈBBЈ, 2 H, 3Ј,6Ј-
(402.576): calcd. C 83.54, H 8.51; found C 83.77, H 8.50.
H), 7.43 (AЈBЈ of AAЈBBЈ, 2 H, 4Ј,5Ј-H), 7.17 (dd, 3JH,H = 7.6 Hz,
4JH,H = 1.6 Hz, 2 H, 6,6ЈЈ-H), 7.04 (dd, JH,H = 7.6 Hz, JH,H
=
3
4
3,3ЈЈ-Di-tert-butyl-2,2ЈЈ-dihydroxy[1,1Ј;3Ј,1ЈЈ]terphenyl (2): A solu-
tion of BBr3 (0.1 in CH2Cl2, 8 mL, 0.8 mmol) was added to a
solution of 13 (0.108 g, 0.268 mmol) in CH2Cl2 (10 mL) at –78 °C.
After stirring for 1.5 h at this temperature, the reaction mixture was
warmed to room temperature. After 5 h stirring the reaction was
quenched by addition of 5% aqueous HCl (10 mL). The aqueous
phase was extracted with CH2Cl2 (3ϫ10 mL). The combined or-
ganic phase was washed with brine (10 mL) and dried (MgSO4),
and the solvent was evaporated. Column chromatography of the
residue (silica, 0–20% heptane in CH2Cl2) afforded diphenol 2 as
a colorless solid (0.052 g). Yield: 52%. M.p. 105–108 °C. 1H NMR
3
1.6 Hz, 2 H, 4,4ЈЈ-H), 6.90 (t, JH,H = 7.6 Hz, 2 H, 5,5ЈЈ-H), 3.07
(s, 6 H, OCH3), 1.05 (s, 18 H, tBu-H) ppm. H NMR (600 MHz,
CD2Cl2, 240 K): δ = 7.44 (AAЈBBЈ, 4 H, 3Ј,6Ј-H and 4Ј,5Ј-H), 7.15
(dd, JH,H = 7.8 Hz, JH,H = 1.8 Hz, 2 H, 4,4ЈЈ-H), 7.04 (dd, JH,H
= 7.8 Hz, JH,H = 1.8 Hz, 6,6ЈЈ-H), 6.88 (t, JH,H = 7.8 Hz, 2 H,
5,5ЈЈ-H), 3.06 (s, 6 H, OCH3), 1.05 (s, 18 H, tBu-H) ppm. 13C NMR
(126 MHz, C2D2Cl4, 278.5 K): δ = 156.9 (2,2ЈЈ-C), 141.3 (3,3ЈЈ-C),
139.7 (1Ј,2Ј-C), 135.0 (1,1ЈЈ-C), 130.4 (3Ј,6Ј-C), 130.3 (6,6ЈЈ-C),
127.5 (4Ј,5Ј-C), 125.6 (4,4ЈЈ-C), 122.1 (5,5ЈЈ-C), 60.0 (OCH3), 34.6
[C(CH3)3], 30.5 [C(CH3)3] ppm. Data for 16-syn: 1H NMR
1
3
4
3
4
3
(500 MHz, C2D2Cl4, 275 K): δ = 7.67 (dd, JH,H = 5.6 Hz, JH,H
=
3
(500 MHz, CDCl3): δ = 7.64 (t, JH,H = 7.5 Hz, 1 H, 5Ј-H), 7.60
(t, JH,H = 1.6 Hz, 1 H, 2Ј-H), 7.54 (dd, JH,H = 7.5 Hz, JH,H
1.6 Hz, 2 H, 4Ј-H and 6Ј-H), 7.35 (dd, JH,H = 7.7 Hz, JH,H
1.6 Hz, 2 H, 4,4ЈЈ-H), 7.15 (dd, JH,H = 7.7 Hz, JH,H = 1.6 Hz, 2
3.4 Hz, 2 H, 3Ј,6Ј-H), 7.42 (dd, JH,H = 5.6 Hz, JH,H = 3.4 Hz, 2 H,
4
3
4
=
=
3
3
4Ј,5Ј-H), 7.09 (d, JH,H = 7.6 Hz, 2 H, 4,4ЈЈ-H), 6.76 (t, JH,H
=
3
4
3
7.6 Hz, 2 H, 5,5ЈЈ-H), 6.65 (d, JH,H = 7.6 Hz, 2 H, 6,6ЈЈ-H), 3.36
(s, 6 H, OCH3), 1.19 (s, 18 H, tBu-H) ppm. H NMR (600 MHz,
3
4
1
3
H, 6,6ЈЈ-H), 6.97 (t, JH,H = 7.7 Hz, 2 H, 5,5ЈЈ-H), 5.48 (s, 2 H,
CD2Cl2, 240 K): δ = 7.63 (d, JH,H = 5.7 Hz, JH,H = 3.3 Hz, 2 H,
3Ј,6Ј-H), 7.40 (dd, JH,H = 5.7 Hz, JH,H = 3.3 Hz, 2 H, 4Ј,5Ј-H),
OH), 1.48 (s, 18 H, tBu-H) ppm. 13C NMR (125 MHz, CDCl3): δ
= 151.1, 138.9, 136.7, 130.9, 130.5, 129.1, 128.4, 128.2, 127.1, 120.3,
35.1, 29.8 ppm. C26H30O2·H2O (392.54): calcd. C 79.56, H 8.22;
found C 80.08, H 7.89.
7.07 (dd, 3JH,H = 8.0 Hz, JH,H = 1.5 Hz, 4,4ЈЈ-H), 6.74 (t, JH,H
=
4
3
3
4
8.0 Hz, 2 H, 5,5ЈЈ-H), 6.63 (dd, JH,H = 8.0 Hz, JH,H = 1.5 Hz, 2
H, 6,6ЈЈ-H), 3.32 (s, 6 H, OCH3), 1.16 (s, 18 H, tBu-H) ppm. 13C
NMR (126 MHz, C2D2Cl4, 278.5 K): δ = 157.4 (2,2ЈЈ-C), 142.7
(3,3ЈЈ-C), 138.7 (1Ј,2Ј-C), 134.5 (1,1ЈЈ-C), 130.8 (3Ј,6Ј-C), 130.5
(6,6ЈЈ-C), 127.3 (4Ј,5Ј-C), 125.6 (4,4ЈЈ-C), 122.3 (5,5ЈЈ-C), 60.3
(OCH3), 34.9 [C(CH3)3], 30.6 [C(CH3)3] ppm. C28H34O2 (402.576):
calcd. C 83.54, H 8.51; found C 83.26, H 8.30.
2Ј-Bromo-3-tert-butyl-2-methoxybiphenyl (15): [Pd(PPh3)4] (0.034 g,
0.0294 mmol) and a solution of K2CO3 (0.622 g, 4.5 mmol) in
water (1.5 mL) were added to a solution of boronic acid 10
(0.836 g, 4 mmol) and 1,2-dibromobenzene (14; 0.13 mL,
1.08 mmol) in DME (15 mL). The reaction mixture was heated at
reflux for 60 h under vigorous stirring. The solvents were evapo-
rated, and the residue was purified by column chromatography
(alumina; heptane/CH2Cl2, 9:1) to afford 15 (0.340 g) as a colorless
3,3ЈЈ-Di-tert-butyl-2,2ЈЈ-dihydroxy[1,1Ј;2Ј,1ЈЈ]terphenyl (3): A solu-
tion of BBr3 (0.1 in CH2Cl2, 8 mL, 0.8 mmol) was added to a
solution of 16 (0.108 g, 0.268 mmol) in CH2Cl2 (10 mL) at –78 °C.
After 1.5 h stirring at this temperature, the reaction mixture was
warmed to room temperature and further stirred for 24 h. The reac-
tion was quenched with 5% aqueous HCl (10 mL). The aqueous
phase was extracted with CH2Cl2 (3ϫ10 mL). The combined or-
ganic extract was washed with brine (10 mL) and dried (MgSO4),
and the solvents were evaporated. Column chromatography of the
residue (silica; heptane/CH2Cl2, 8:2) afforded diphenol 3 (0.078 g)
as a pale-yellow solid. Yield: 78%. M.p. 128–132 °C. 1H NMR
(500 MHz, C2D2Cl4, 400 K): δ = 7.57 (br. s, 4 H, 3Ј,6Ј-H and 4Ј,5Ј-
H), 7.15 (d, 3JH,H = 7.6 Hz, 2 H, 4,4ЈЈ-H or 6,6ЈЈ-H), 7.06 (d, 3JH,H
1
3
oil. Yield: 98%. H NMR (500 MHz, CDCl3): δ = 7.76 (dd, JH,H
4
3
= 7.8 Hz, JH,H = 1.1 Hz, 1 H, 3Ј-H), 7.47 (dd, JH,H = 7.8 Hz,
4JH,H = 1.7 Hz, 1 H, 6Ј-H), 7.44 (dd, JH,H = 7.5 Hz, JH,H
=
3
4
3
4
2.0 Hz, 1 H, 6-H), 7.41 (td, JH,H = 7.8 Hz, JH,H = 1.1 Hz, 1 H,
5Ј-H), 7.26 (td, JH,H = 7.8 Hz, JH,H = 1.7 Hz, 1 H, 4Ј-H), 7.18
(dd, JH,H = 7.5 Hz, JH,H = 2.0 Hz, 1 H, 4-H), 7.14 (t, JH,H
7.5 Hz, 1 H, 5-H), 3.35 (s, 3 H, OCH3), 1.52 (s, 9 H, tBu-H) ppm.
13C NMR (125 MHz, CDCl3): δ = 157.6, 142.8, 140.8, 134.6, 133.1,
132.1, 130.3, 128.8, 127.3, 126.8, 125.6, 124.0, 122.6, 122.3, 60.4,
35.2, 30.8 ppm. C17H19BrO (319.24): calcd. C 63.96, H 6.00; found
C 62.72, H 6.33.
3
4
3
4
3
=
3
= 7.6 Hz, 2 H, 6,6ЈЈ-H or 4,4ЈЈ-H), 6.76 (t, JH,H = 7.6 Hz, 2 H,
5,5ЈЈ-H), 4.87 (br. s, 2 H, OH), 1.33 (s, 18 H, tBu-H) ppm. Data
for 3-anti: H NMR (500 MHz, C2D2Cl4, 240 K): δ = 7.56 (AB of
AAЈBBЈ, 2 H, 3Ј,6Ј-H), 7.50 (AЈBЈ of AAЈBBЈ, 2 H, 4Ј,5Ј-H), 7.08
3,3ЈЈ-Di-tert-butyl-2,2ЈЈ-dimethoxy[1,1Ј;2Ј,1ЈЈ]terphenyl (16)
Method A: [Pd(PPh3)4] (0.043 g, 0.0372 mmol) and K2CO3 (0.310 g,
2.25 mmol) were added to a solution of 15 (0.120 g, 0.376 mmol)
and boronic acid 10 (0.313 g, 1.5 mmol) in DMF (8 mL). The reac-
tion mixture was stirred vigorously at 100 °C for 16 h. The solvent
was removed in vacuo. Column chromatography of the residue
(alumina, heptane) afforded 16 (0.147 g) as a colorless solid in 97%
yield.
1
3
4
3
(dd, JH,H = 7.5 Hz, JH,H = 1.5 Hz, 2 H, 4,4ЈЈ-H), 6.96 (dd, JH,H
4
3
= 7.5 Hz, JH,H = 1.5 Hz, 2 H, 6,6ЈЈ-H), 6.77 (t, JH,H = 7.5 Hz, 2
H, 5,5ЈЈ-H), 4.83 (s, 2 H, OH), 1.12 (s, 18 H, tBu-H) ppm. 1H NMR
(600 MHz, CD2Cl2, 240 K): δ = 7.56 (AB of AAЈBBЈ, 2 H, 3Ј,6Ј-
H), 7.50 (AЈBЈ of AAЈBBЈ, 2 H, 4Ј,5Ј-H), 7.08 (dd, 3JH,H = 7.5 Hz,
3
4
Method B: [Pd(PPh3)4] (0.070 g, 0.0606 mmol) and K2CO3 (1.66 g,
12.0 mmol) were added to a solution of 1,2-dibromobenzene (14;
0.49 g, 2.0 mmol) and boronic acid 10 (1.704 g, 8.15 mmol) in
4JH,H = 1.5 Hz, 2 H, 4,4ЈЈ-H), 6.93 (dd, JH,H = 7.5 Hz, JH,H
=
3
1.5 Hz, 2 H, 6,6ЈЈ-H), 6.68 (t, JH,H = 7.5 Hz, 2 H, 5,5ЈЈ-H), 4.95
(s, 2 H, OH), 1.16 (s, 2 H, tBu-H) ppm. 13C NMR (151 MHz,
DMF (18 mL). The reaction mixture was stirred vigorously at C2D2Cl4, 273 K): δ = 152.2 (2,2ЈЈ-C), 138.8 (1Ј,2Ј-C), 137.6 (3,3ЈЈ-
100 °C for 6 h. After addition of an extra portion of 14 (0.1 mL,
0.83 mmol), the reaction mixture was stirred overnight at 100 °C
and the solvent was evaporated. Column chromatography (alu-
mina, heptane) of the residue afforded 16 (0.729 g) in 64% yield.
C), 133.5 (4Ј,5Ј-C), 131.1 (3Ј,6Ј-C), 129.3 (6,6ЈЈ-C), 129.2 (1,1ЈЈ-C),
128.3 (4,4ЈЈ-C), 121.5 (5,5ЈЈ-C), 36.1 (C(CH3)3), 31.0
(C(CH3)3) ppm. Data for 3-syn: 1H NMR (500 MHz, C2D2Cl4,
3
240 K): δ = 7.53 (s, 4 H, 3Ј,4Ј,5Ј,6Ј-H), 7.06 (dd, JH,H = 7.5 Hz,
Eur. J. Org. Chem. 2009, 6318–6327
© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjoc.org
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