CHEN Et al.
7 of 9
|
used, and samples were dissolved in THF (ca. 1 mg/mL).
HPLC grade THF was used for GPC.
4
.4
Synthesis of compound (4)
|
To a stirred suspension of magnesium (0.050 g, 2.1 mmol)
in THF (10 mL) was added dropwise bromobenzene (0.30 g,
4
.2
Synthesis of PCl (CH Cl)
|
2
2
1
.9 mmol). The reaction mixture was refluxed at 75°C for
PhPCl (8.99 g, 50.2 mmol) was added to ClCH P(S)Cl
2 hours. This freshly made Grignard reagent was added
2
2
2
(
8.01 g, 43.7 mmol) at 175°C with vigorous stirring, and the
color of solution changed from colorless to light yellow after
hours. Compound ClCH PCl , with PCl as minor impurity,
dropwise to the 2 (0.19 g, 0.80 mmol) dissolved in THF
3
1
(5 mL) at −78°C. The reaction was monitored by P NMR
spectroscopy. Light yellow solution slowly turned to color-
less after stirring for 15 hours. The solvent was removed in
vacuo, leaving a white residue. The residue was dissolved in
degassed EtOH (3 × 5 mL), and the suspension was filtered.
The solvent was removed in vacuo leaving white solid prod-
uct. Yield = 0.094 g (37%).
7
2
2
3
was isolated by reduced pressure distillation of the reaction
mixture using water aspirator (1.0 Torr) and heating by oil
bath (T = 40-80°C). The product was collected in a Schlenk
flask immersed in liquid nitrogen. A second atmospheric
pressure distillation heated with an oil bath (T = 140-145°C)
to afford pure ClCH PCl (b.p. 125°C)—the first drops con-
3
1
1
P NMR (161.9 MHz, CDCl3): δ -18.8 (s); H NMR
2
2
tained PCl and were discarded. Yield = 3.12 g (47%)
(400.1 MHz, CDCl3): δ 7.29-7.19 (m, 10H, aryl H), 6.88
3
3
1
1
2
2
P NMR (161.9 MHz, CDCl , 298 K): δ 159.2 (s); H
(s, 2H, Mes), 3.65 (dd, JHH = −13.3 Hz, JPH = 33.1 Hz,
3
2
2
2
NMR (400.1 MHz, CDCl , 298 K): δ 4.10 (d, J = 16.0 Hz,
1H, -CH2-), 3.55 (dd, JHH = −13.4 Hz, JPH = 33.4 Hz,
3
PH
1
3
1
13
2
4
H, -CH -); C{ H} NMR (100.6 MHz, CDCl , 298 K) δ
1H, -CH2-), 2.28 (s, 3H, p-CH3), 2.20 (s, 6H, o-CH3); C
2
3
2
8.2 (d, J = 55.8 Hz, 2H, -CH -).
NMR (100.6 MHz, CDCl3): δ 145.0 (s, aryl C),141.5 (d,
PC
2
2
J
= 16.9 Hz, aryl C), 137.1 (d, J = 10.8 Hz, aryl C), 129.5
PC
(
s, aryl C), 129.4 (s, aryl C), 129.1 (s, aryl C), 129.0 (s, aryl
4
.3
Synthesis of MesPCl(CH Cl) (2)
|
2
C),128.9 (s, aryl C), 128.3 (s, aryl C), 128.2 (s, aryl C), 126.5
1
To a stirred suspension of activated Mg (0.98 g, 40.4 mmol)
in THF (25 mL) was added bromomesitylene (5.06 mL,
(s, aryl C), 125.9 (s, aryl C), 33.8 (d, JPC = 18.4 Hz, -CH2-),
23.2 (s, o-CH3), 23.1 (s, o-CH3), 21.0 (s, p-CH3); MS (EI):
3
1
+
3
3.1 mmol) dropwise. The reaction was monitored by
P
m/z 319, 318 [39, 100, M ].
NMR spectrometry. After refluxing for 2 hours, the Grignard
reagent was formed as evidenced by the deep brown color. It
was cannula-transferred into a THF solution of ClCH PCl
4
.5
Trapping Product (5)
|
2
2
(
4.17 g, 27.6 mmol) (25 mL) dropwise at −78°C. The reac-
To a stirred solution of 2 (0.20 g, 0.85 mmol) in THF
(10 mL) at −78°C was added in small portions MgA·3THF
(0.36 g, 0.85 mmol) as an orange powder. The color of the
solution gradually changed from colorless to yellow to dark
blue-green after 9 hours. The reaction was monitored by
tion mixture was warmed to room temperature and the solvent
was removed in vacuo, leaving a yellow oil. To the yellow oil
was added hexanes (3 × 10 mL), and the suspension was fil-
tered, and the solvent was removed in vacuo to obtain a light
3
1
yellow oil containing 2 and MesPBr(CH Cl).
P NMR spectrometry with the major signal at −42.2 ppm.
2
To a stirred solution of the above mixture (0.50 g,
1,3-Cyclohexadiene (0.10 mL, 1.0 mmol) was added drop-
wise into the dark blue-green reaction mixture. The reaction
mixture was slowly warmed to ambient temperature and its
1
.9 mmol) dissolved in THF (5 mL) was added dropwise
tetrabutylammonium chloride (0.60 g, 2.2 mmol) in THF
5 mL). After vigorous stirring for 10 minutes, the solvent
3
1
(
color changed from dark blue-green to yellow. A P NMR
spectrum was recorded. The solution was filtered and the sol-
vent was removed in vacuo, affording a small quantity of yel-
low solid, sufficient only for MS analysis.
was removed in vacuo, leaving a pale yellow colored residue.
To the residue was added hexanes (3 × 3 mL), the soluble
portion was filtered, and the solvent removed in vacuo to af-
ford 2. Yield = 3.70 g (57%).
3
1
P NMR (161.9 MHz, THF): δ = −17.3 (s), −42.2 (s).
3
1
1
+
P NMR (161.9 MHz, CDCl , 298 K): δ 74.9 (s); H
MS (EI): m/z = 244 [M ].
3
NMR (400.1 MHz, CDCl , 298 K): δ 6.95 (s, 2H, aryl H),
.34 (dd,
dd,
3
2
2
4
J
= 11 Hz,
J
= 24 Hz, 1H, -CH -), 4.27
HH
HP 2
4
.6
Reaction of 2 with MgA·3THF
2
2
|
(
J
= 11 Hz,
J
= 28 Hz, 1H, -CH -), 2.69 (d,
HH
HP
2
4
13
J
= 2 Hz, 6H, o-CH ), 2.33 (s, 3H, p-CH ); C NMR
To a stirred solution at −78°C of 2 (0.20 g, 0.85 mmol) dis-
solved in THF (10 mL) was added MgA۰3THF (0.36 g,
0.85 mmol) orange powder in small portions. The color of
the solution gradually changed from colorless to yellow to
dark blue-green after 9 hours. The reaction was monitored
HP
3
3
(
100.6 MHz, CDCl , 298 K): δ 144.1 (s, aryl C), 143.9 (s,
3
aryl C),141.7 (s, aryl C), 130.3 (s, aryl C), 130.1 (s, aryl C),
1
1
27.0 (s, aryl C), 126.3 (s, aryl C), 42.4 (d, J = 42 Hz,
CP
2
-
(
CH -), 22.4 (d, J = 22 Hz, o-CH ), 21.5 (s, p-CH ); MS
2
CP
3
3
+
31
EI) : m/z = 236, 234 [60, 100, M ].
by P NMR spectrometry. After 9 hours, the reaction was