The Journal of Organic Chemistry
Note
heptane and pentane and recrystallized from a saturated DCM
solution overlaid with hexane at room temperature. Then, 880 mg of a
crystalline yellowish solid was obtained (2.64 mmol, 75% yield). H
136.0 (C), 135.7 (C), 133.7 (CH), 133.3 (CH), 132.6 (CH), 132.1
(CH), 131.7 (C), 130.2 (C), 129.0 (CH), 128.9 (CH), 125.8 (CH),
124.9 (CH), 121.0 (C), 120.1 (CH), 119.1 (CH), 115.8 (C), 30.4
1
+•
+•
NMR (301 MHz, in CDCl ): δ 7.83 (ddd, J = 9.8, 7.8, 1.3 Hz, 3H),
(CH ), 30.1 (CH ). HRMS (EI) m/z: [M ] calcd for [C H Br ] ,
3
2 2 22 14 2
7
1
.77−7.68 (m, 1H), 7.49 (dd, J = 8.0, 7.0 Hz, 1H), 7.31 (t, J = 7.8 Hz,
435.9462; found, 435.9462.
1
3
1
H), 1.47 (s, 12H). C{ H} NMR (101 MHz, in CDCl ): δ 135.3
Synthesis of 7-Phenyldinaphtho[1,8-bc:1′,8′-ef]phosphepine 7-
3
(C), 134.5 (C), 133.4 (CH), 130.8 (CH), 130.2 (CH), 128.8 (CH),
Oxide (1). In a 10 mL Schlenk tube, 8,8′-dibromo-1,1′-binaphthalene
1
1
1
1
26.2 (CH), 125.8 (CH), 123.7 (C), 84.3 (C), 25.2 (CH3). B{ H}
(5) (1.0 equiv, 68 μmol, 28 mg) was dissolved in 3.4 mL of dry Et O
2
+•
t
NMR (128 MHz, in CDCl ): δ 31.8 (B). HRMS (EI) m/z: [M ]
calcd for [C H BO Br] , 332.0583; found, 332.0571.
Synthesis of 8,8′-Dibromo-1,1′-binaphthalene (5). In a 250 mL
three-neck round-bottom flask equipped with a condenser, 2-(8-
bromonaphthalen-1-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (3)
and cooled to −78 °C. Then, BuLi (2.0 equiv, 136 μmol, 0.08 mL,
1.7 M in pentane) was added dropwise for 5 min. The lithiated
intermediate was reacted with PhPCl (1.0 equiv, 68 μmol, 9.5 μL,
3
+•
16
18
2
2
9
7%) and warmed up to room temperature. After the mixture was
stirred for 3 h, the solvent was removed under a vacuum. The
intermediate product was dissolved in 2 mL of DCM and 1 mL of
42
(
(
1.0 equiv, 1.5 mmol, 500 mg), 1-bromo-8-iodonaphthalene (4)
1.0 equiv, 1.5 mmol, 500 mg), and Pd(PPh ) (3 mol %, 45 μmol, 52
water and cooled to 0 °C. Two drops of an aqueous H O solution
2
2
3
4
(
34.5−36.5%) were added, and the reaction solution was stirred for
5 min. The solvent was removed, and the crude was subsequently
washed with hexane and pentane to obtain 17 mg (45 μmol) of a
mg) were dissolved in 140 mL of dry toluene. K PO (3.0 equiv, 4.5
mmol, 953 mg) was added, and the reaction mixture was stirred at
3
4
2
1
40 °C for 4 weeks. The reaction was quenched with 80 mL of water,
1
yellowish solid (66% yield). H NMR (301 MHz, in CDCl ): δ 8.84−
and the aqueous layer was extracted with 100 mL of DCM for three
3
8
.77 (dd, J = 14.4, 6.6 Hz, 2H), 8.15−8.12 (d, J = 8.1 Hz, 2H), 7.94−
.91 (d, J = 7.3 Hz, 2H), 7.78−7.73 (t, J = 7.0 Hz, 2H), 7.52−7.46
times. The combined organic layers were dried over MgSO , and the
4
7
solvent was removed under a vacuum. After purification by column
chromatography using alumina and a gradient mixture of hexane and
toluene as an eluent (0.95:0.05 to 0.7:0.3), 50 mg (0.12 mmol) of a
(
m, 4H), 7.12−7.09 (t, J = 7.2 Hz, 1H), 6.98−6.94 (t, J = 6.0 Hz,
13 1
2
H), 6.83−6.76 (dd, J = 12.2, 7.4 Hz, 2H). C{ H} NMR (101
1
MHz, in CD Cl ): δ 140.2 (C), 136.1 (CH), 134.8 (d, J = 4.7 Hz,
colorless solid was obtained (40% yield). H NMR (400 MHz, in
2 2
CH), 134.0 (d, J = 3.2 Hz, CH), 133.8 (CH), 132.0 (C), 131.1 (CH),
30.2 (d, J = 2.3 Hz, CH), 130.1 (CH), 128.9 (d, J = 12.4 Hz, C),
128.6 (C), 128.1 (CH), 128.0 (CH), 126.8 (C), 126.4 (C), 125.7
CDCl ): δ 7.96−7.90 (ddd, J = 12.2, J = 8.2 Hz, 4H), 7.78−7.75 (dd,
3
1
J = 7.4 Hz, 2H), 7.50−7.46 (t, J = 8.1 Hz, 2H), 7.34−7.32 (dd, J =
1
3
1
7
.1, 1.3 Hz, 2H), 7.31−7.29 (d, J = 7.9 Hz, 2H). C{ H} NMR (101
3
1
1
(
CH), 125.6 (d, J = 12.3 Hz, CH). P{ H} NMR (162 MHz, in
MHz, in CDCl ): δ 140.3 (C), 135.9 (C), 133.5 (CH), 131.8 (CH),
3
+
•
CDCl ): δ 24.10 (P). HRMS (EI) m/z: [M ] calcd for
[C H OP] , 376.1017; found, 376.1024.
1
31.4 (C), 129.2 (CH), 129.1 (CH), 126.0 (CH), 125.1 (CH), 121.1
3
+•
+•
+•
(C). HRMS (EI) m/z: [M ] calcd for [C H Br ] , 409.9306;
26 17
2
0
12
2
Synthesis of 5-Phenyl-1,2-dihydroacenaphtho[5,6-bc]naphtho-
1,8-ef ]phosphepine 5-Oxide (2). In a 10 mL Schlenk tube, 5-bromo-
found, 409.9299.
[
Synthesis of 5,6-Dibromo-1,2-dihydroacenaphthylene (6). This
6
-(8-bromonaphthalen-1-yl)-1,2-dihydroacenaphthylene (7) (1.0
compound was synthesized according to a modified protocol
50
equiv, 80 μmol, 35 mg) was dissolved in 4 mL of dry Et O and
cooled to −78 °C. Then, BuLi (2.0 equiv, 0.16 mmol, 0.09 mL, 1.7 M
in pentane) was added dropwise. The lithiated intermediate was
2
described elsewhere. In a 250 mL flame-dried round-bottom flask
equipped with a Schlenk adapter, 1,2-dihydroacenaphthylene (1.0
equiv, 129.7 mmol, 20 g) was dissolved in 25 mL of dry DMF. The
reaction solution was cooled to 10 °C, and an NBS suspension (2.15
equiv, 278.9 mmol, 50.09 g, in 80 mL of dry THF) was added
dropwise via a dropping funnel over a time of 20 min. The solution
was stirred at 10 °C for 18 h, protected from light, and was warmed
up to room temperature. A beige solid precipitate was filtered from
the reaction solution and washed three times with 125 mL of EtOH.
After drying under a vacuum at 40 °C, the product was obtained as a
beige solid, which was further crystallized from a mixture of DCM and
t
reacted with PhPCl (1.0 equiv, 80 μmol, 11 μL, 97%), and the
2
reaction warmed up to room temperature. After the mixture was
stirred for 3 h, the solvent was removed under a vacuum. The
intermediate product was dissolved in 2 mL of DCM and 1 mL of
water and cooled to 0 °C. Two drops of an aqueous H O solution
2
2
(
1
34.5−36.5%) were added, and the reaction solution was stirred for
0 min. The solvent was removed, and the crude was purified by
column chromatography using silica and the mixture of DCM/
MeOH/NH (aq) = 100:4:0.5 (v/v/v) to isolate 7 mg (17 μmol) of a
3
CHCl and upon cooling in the fridge. Yield: 25% (10.24 g, 32.82
3
1
1
pale yellow solid (22% yield). H NMR (600 MHz, in CDCl
8.84−8.67 (ddd, J = 84.9, 14.3, 6.9 Hz, 2H), 8.02−8.01 (d, J = 8.0 Hz,
3
): δ
mmol). H NMR (301 MHz, in CDCl ): δ 7.81−7.78 (d, J = 7.4 Hz,
3
1
3
1
2
H), 7.11−7.08 (d, J = 7.4 Hz, 2H), 3.31 (s, 4H). C{ H} NMR
1
H), 7.81−7.80 (d, J = 7.6 Hz, 1H), 7.76−7.75 (d, J = 7.1 Hz, 1H),
(101 MHz, in CDCl ): δ 147.1 (C), 142.0 (C), 135.9 (CH), 127.9
3
+•
7.70−7.67 (t, J = 7.3 Hz, 1H), 7.64−7.63 (d, J = 6.7 Hz, 1H), 7.46−
7.42 (dd, J = 14.5, 7.3 Hz, 2H), 7.36−7.35 (d, J = 7.5 Hz, 1H), 7.12−
(C), 121.0 (CH), 114.4 (C), 30.1 (CH ). MS (EI) m/z: [M ] calcd
2
+•
for [C H Br ] , 309.8993; found, 310.
12
8
2
7
.10 (t, J = 7.4 Hz, 1H), 7.00−6.96 (t, J = 5.2 Hz, 2H), 6.83−6.79
Synthesis of 5-Bromo-6-(8-bromonaphthalen-1-yl)-1,2-dihy-
droacenaphthylene (7). In a 100 mL two-neck round-bottom flask
equipped with a condenser, 2-(8-bromonaphthalen-1-yl)-4,4,5,5-
tetramethyl-1,3,2-dioxaborolane (3) (1.0 equiv, 1.50 mmol, 170
mg), 5,6-dibromo-1,2-dihydroacenaphthylene (6) (1.0 equiv, 0.51
mmol, 159 mg), and Pd(PPh ) (3 mol %, 15 μmol, 18 mg) were
13 1
(
dd, J = 12.1, 7.7 Hz, 2H), 3.57−3.43 (m, 4H). C{ H} NMR (151
MHz, CDCl ): δ 152.9 (C), 148.1 (C), 140.1 (C), 139.9 (CH), 136.7
3
(
C), 136.5 (CH), 135.0 (C), 133.9 (CH), 133.1 (C), 133.0 (CH),
1
1
1
32.7 (C), 131.7 (CH), 130.9 (CH), 130.2 (d, J = 10.6 Hz, CH),
29.1 (CH), 128.8 (C), 127.9 (d, J = 12.4 Hz, CH), 126.5 (CH),
25.4 (d, J = 12.5 Hz, CH), 123.6 (C), 122.9 (C), 121.3 (CH), 120.1
3
4
dissolved in 48 mL of dry toluene. K PO (3 equiv, 1.53 mmol, 223
3
4
31
1
(
d, J = 12.1 Hz, CH), 31.1 (CH ), 29.9 (CH ). P{ H} NMR (243
2 2
mg) was added, and the reaction mixture was stirred at 115 °C for 2
weeks and 4 days. The reaction was quenched with 30 mL of water,
and the aqueous layer was extracted with 60 mL of DCM three times.
+
•
MHz, CDCl ): δ 23.97 (P). HRMS (EI) m/z: [M ] calcd for
3
+•
[C H OP] , 402.1173; found, 402.1166.
2
8
19
The combined organic layers were dried over MgSO , and the solvent
4
ASSOCIATED CONTENT
Supporting Information
was removed under a vacuum. After purification by column
chromatography using silica and a gradient mixture of hexane and
toluene as an eluent (0.90:0.1 to 0.70:0.3), 54 mg (0.12 mmol) of a
■
*
S
1
pale beige solid was isolated (24% yield). H NMR (301 MHz, in
CDCl ): δ 7.95−7.89 (ddd, J = 14.8, 8.2, 1.1 Hz, 2H), 7.76−7.74 (dd,
3
Crystallographic data; DFT calculations; temperature-
J = 7.4, 1.2 Hz, 1H), 7.64−7.63 (d, J = 7.3 Hz, 1H), 7.51−7.47 (t, J =
7
.1 Hz, 1H), 7.39−7.37 (dd, J = 7.1, 1.4 Hz, 1H), 7.31−7.27 (m, 3H),
13 1
7
.14−7.12 (d, J = 7.3 Hz, 1H), 3.50−3.41 (m, 4H). C{ H} NMR
(
101 MHz, in CDCl ): δ 146.4 (C), 146.3 (C), 140.7 (C), 139.3 (C),
3
D
J. Org. Chem. XXXX, XXX, XXX−XXX