Synthesis of functional phosphines with ortho-substituted aryl groups: 2-RC6H4PH2 and 2-RC6H 4P(SiMe3)2 (R = 2-/-Pr- or 2-f-Bu-)

Article abstract of DOI:10.1002/hc.20606

The synthesis and characterization of 2- i-PrC₆H ₄PCl₂ (3), 2-t-BuC₆H₄PCl₂ (4), 2-i-PrC₆H₄PH₂ (5), 2-t-BuC ₆H₄PH₂ (6), 2-i-PrC₆H ₄P(SiMe₃)₂ (7), and 2-t-BuC₆H ₄P(SiMe₃)₂ (8) are described.

Full text of DOI:10.1002/hc.20606

Heteroatom Chemistry
Volume 21, Number 4, 2010
Synthesis of Functional Phosphines with
Ortho-Substituted Aryl Groups: 2-RC H PH
6 4 2
and 2-RC H P(SiMe ) (R = 2-i-Pr- or
6 4
3 2
2-t-Bu-)
Julien Dugal-Tessier, Paul-Steffan Kuhn, Gregory R. Dake,
and Derek P. Gates
Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British
Columbia, Canada, V6T 1Z1
Received 15 February 2010; revised 7 April 2010
Combining a P-aryl substituent with P-H or
ABSTRACT: The synthesis and characterization of 2-
P-SiMe3 functional groups at phosphorus results
in reactive phosphines that are important building
blocks in organic, main group, and organometallic
i-PrC6H4PCl2 (3), 2-t-BuC6H4PCl2 (4), 2-i-PrC6H4PH2
(5), 2-t-BuC6H4PH2 (6), 2-i-PrC6H4P(SiMe3)2 (7),
ꢀ
C
and 2-t-BuC6H4P(SiMe3)2 (8) are described.
2010
chemistry [4,5]. Several representative reactions are
shown in Scheme 1 to illustrate the utility of phos-
phines with P-Si functionalities. Phosphines with a
single trimethylsilyl substituent may be employed
to functionalize alkenes and alkynes A [6–12], ring-
open epoxides B [13], add to aldehydes C [13–15],
and support metal-catalyzed coupling reactions D
[16–18]. In addition, bis(trimethylsilyl)phosphines
are important precursors to diphosphenes E [19],
and phosphaalkenes F [20] when appropriately
bulky aryl substituents (Ar) are employed.
We [21], and others [22], are interested in the de-
velopment of applications for phosphaalkenes in ar-
eas such as polymer science and catalysis (Scheme 2,
I and II). We have demonstrated that a delicate
balance between kinetic and thermodynamic sta-
bility is required to afford isolable but polymeriz-
able monomers. For example, mesityl-substituted
MesP CPh2 polymerizes [23], whereas we have
been unsuccessful in polymerizing supermesityl-
substituted Mes∗P CH2 [24]. The polymerization
of P C bonds opens the door to the generation
of a wide range of functional homopolymers, or
block- or random-copolymers, that are effective
in binding transition metals [25,26], forming self-
assembled nanostructures, and as ligands for use
Wiley Periodicals, Inc. Heteroatom Chem 21:265–
270, 2010; Published online in Wiley InterScience
(www.interscience.wiley.com). DOI 10.1002/hc.20606
INTRODUCTION
The development of chemically functional phos-
phines bearing sterically encumbering substituents
has had a profound impact on the low-coordinate
chemistry of phosphorus. For example, the em-
ployment P-substituents such as 2,4,6-Me3C6H2
(mesityl, Mes) and 2,4,6-t-Bu3C6H2 (supermesityl,
Mes∗) permitted the isolation of the phosphaalkene
MesP CPh2 [1] and the diphosphene Mes∗P PMes∗
[2]. Recently, the development of bulkier and more
sophisticated aryl substituents [e.g., 2,6-{2,4,6-(i-
Pr)3C6H2}2C6H3
and 2,4,6-{CH(SiMe3)2}3C6H2
]
led to the isolable compounds of the heavier ele-
ments of the periodic table with low-coordination
numbers [3].
Correspondence to: Gregory R. Dake; e-mail: gdake@chem
.ubc.ca. Derek P. Gates; e-mail: dgates@chem.ubc.ca.
c
ꢀ
2010 Wiley Periodicals, Inc.
265

266 Dugal-Tessier et al.
OSiR3
PPh2
OSiR3
PPh2
Ph
Ph
O
R1 = Ph
Ar = Ph
R1 = Ph
Ar = Ph
O
H
B
C
I
R
SiR3
P Me
Ph
Ph
[L*Pd]
Ph
Ar P
Ph2P
R1 = Ph
Ar = Ph
A
R1 = Me
Ar = Ph
D
R1
R
O
R
Ar
PCl2
F
E
R
R1 = SiMe3 R1 = SiMe3
Ar
Ar
P
P
P
C
Ar
R
R
SCHEME 1
in polymer-supported catalysts [27]. In addition, we
have recently been interested in the development of
phosphaalkene-based ligands for use in asymmetric
catalysis (Scheme 2, II) [28,29].
RESULT AND DISCUSSION
The synthesis starts with aryl bromides 1 and 2, pre-
pared from the corresponding commercially avail-
able aniline derivatives using a Sandmeyer reaction
[30] (Scheme 3). The addition of magnesium metal
to the aryl bromide (1 or 2) in tetrahydrofuran (THF)
generates the respective Grignard reagents, which
are then treated with ClP(NEt2)2 [31]. The use of
diethylamino-protected chlorophosphine instead of
PCl3 ensures that only a single aryl-substitution oc-
curs at phosphorus. Analysis of the product by 31P
NMR spectroscopy confirms that only a single prod-
uct is formed, and the chemical shift is consistent
with its formulation as 2-RC6H4P(NEt2)2 (R = i-Pr:
δ = 94; R = t-Bu: δ = 93). Although it is possible to
isolate the bis(aminophosphines), we found it more
convenient to simply treat the crude product with an-
hydrous hydrogen chloride in CH2Cl2 to remove the
diethylamino protecting groups. The dichlorides 3
and 4 are obtained in satisfactory overall yields after
distillation (69% and 78%, respectively). The prod-
ucts were analyzed by 31P NMR spectroscopy (3: δ =
164, 4: δ = 166). These chemical shifts are similar
to related dichloroarylphosphines such as MesPCl2
(δ = 167) [32].
To tune the steric properties of phosphaalkenes
for application in catalysis and polymer science,
we have been interested in the development of
moderately bulky P-aryl substituents with a sin-
gle substituent in the ortho-position. Since (2-
MeC6H4)P CPh2 was reported to be unstable [1],
we pursued the preparation of systems with the
slightly larger i-Pr or t-Bu substituent in the 2-
position of the aryl substituent. Herein, we re-
port the synthesis of the new primary phosphines
2-i-PrC6H4PH2 and 2-t-BuC6H4PH2 as well as the
bis(trimethylsilyl)phosphines 2-i-PrC6H4P(SiMe3)2
and 2-t-BuC6H4P(SiMe3)2. This synthetic methodol-
ogy is amenable to the isolation of multigram quanti-
ties of material from commercially available starting
materials.
R
M
Ar
Ar
Ph
C
P
C
N
Initiator
P
C
n
P
Reduction of the dichlorides 3 and 4 using
LiAlH4 affords primary phosphines 5 and 6 in good
isolated yield (70% and 82%, respectively). Although
phosphine 5 has previously been mentioned, its syn-
thesis and characterization were not reported [33].
O
Ph
Ph
Ph
Ar Ph
n
I
II
SCHEME 2
Heteroatom Chemistry DOI 10.1002/hc

Synthesis of Functional Phosphines with Ortho-Substituted Aryl Groups 267
(1) Mg, THF
(2) ClP(NEt2)2
R
R
R
(1) 48% HBr, NaNO2
(2) 48% HBr, CuBr
(3) HCl(g), CH2Cl2
NH2
Br
PCl2
1 R=i-Pr (46%)
2 R=t-Bu (30%)
3 R=i-Pr (69%)
4 R=t-Bu (78%)
(1) MeLi, THF,
–78°C to rt
R
R
R
LiAlH4 (0.75 equiv.)
(2) Me3SiCl, THF,
–78°C to rt
Et2O, –78°C to rt
PCl2
PH2
P(SiMe3)2
5 R=i-Pr (48%)
6 R=t-Bu (72%)
3 R=i-Pr
4 R=t-Bu
7 R=i-Pr (70%)
8 R=t-Bu (82%)
SCHEME 3
Analysis of the products using 31P NMR spectroscopy
revealed triplet resonances that are characteristic of
primary phosphines [5: δ = −127 (t, 1 JPH = 203 Hz),
2-t-BuC6H4-substituted phosphines have been pre-
pared and fully characterized spectroscopically. This
synthetic route is amenable to the preparation of
multigram quantities of product in a linear fash-
ion. The new bis(trimethylsilyl)arylphosphines (7
and 8) are of interest for the synthesis of new phos-
phaalkenes for applications as supporting ligands for
metal-catalyzed organic transformations.
1
6: δ = −107 ppm (t, JPH = 202 Hz)]. Interestingly,
these signals are shifted downfield when compared
to MesPH2(−149 ppm, t, 1 JPH = 203 Hz) [32] and the
chemical shift for 6 is closer to alkyl phosphines such
1
as t-BuPH2 (−80 ppm, t, JPH = 180 Hz) and (cyclo-
1
C6H11)PH2 (−111 ppm, t, JPH = 187 Hz) [32]. Com-
pounds 5 and 6 were further characterized by 1H and
1
13C{ H} NMR spectroscopy, and mass spectrometry,
EXPERIMENTAL
General Procedures
each of which supported the assigned structures.
Owing to the difficulty handling pyrophoric phos-
phines 5 and 6, elemental microanalysis could not
be accurately obtained.
All manipulations of air- and/or water-sensitive com-
pounds were performed under a nitrogen atmo-
sphere using standard Schlenk or glovebox tech-
niques. Hexanes and CH2Cl2 were deoxygenated
with nitrogen and dried by passing through a col-
umn containing activated alumina. THF was dis-
tilled from sodium/benzophenone ketyl. Reagents,
2-i-PrC6H4NH2, 2-t-BuC6H4NH2, Mg, Me3SiCl, and
LiAlH4 were purchased from Aldrich and used
as received. Anhydrous HCl was obtained from
BOC Gases and used as received. MeLi in Et2O
was purchased from Aldrich and titrated with N-
benzylbenzamide prior to use.
The final step in the preparation of bis(trimethyl-
silyl)phosphines 7 and 8 involves treating 5 or 6 with
MeLi (2 equiv) followed by silylation using Me3SiCl.
The desired bis(trimethysilyl)phosphines were iso-
lated in reasonable yield after distillation (7: 48%, 8:
72%). Compound 7 and 8 were characterized by 31P,
1
1H, and 13C{ H} NMR spectroscopy, low-resolution
and high-resolution mass spectrometry, and elemen-
tal analysis. Interestingly, the 31P chemical shift of 7
(δ = −153) is similar to MesP(SiMe3)2 (δ = −164),
whereas that for 8 (δ = −135) is similar to alkyl-
substituted cyclo-C6H11P(SiMe3)2 (δ = −139). The 1H
1
1H, 31P, and 13C{ H} NMR spectra were recorded
1
and 13C{ H} NMR spectra of 7 and 8 are consistent
at room temperature on Bruker Avance 300 or
400 MHz spectrometers. 85% H3PO4 was used as an
with the proposed structures.
1
external standard (δ = 0.0 for 31P). H NMR spectra
were referenced to residual protonated solvent, and
SUMMARY
1
13C{ H} NMR were referenced to the deuterated sol-
A synthetic methodology has been developed to
prepare new moderately bulky phosphines from
commercially available 2-substituted anilines. The
chlorides, hydrides, and silylides of 2-i-PrC6H4- and
vent. Elemental analyses were performed in the Uni-
versity of British Columbia Chemistry Microanalysis
Facility. Mass spectra were recorded on a Kratos MS
50 instrument in EI mode (70 eV).
Heteroatom Chemistry DOI 10.1002/hc

268 Dugal-Tessier et al.
2-i-PrC6 H PCl2 (3). To a solution of Mg (2.97 g,
solution of 3 (15.5 g, 70 mmol) in Et2O (15 mL) was
added. The cooling bath was removed, and the so-
lution was warmed to room temperature. 31P NMR
analysis of an aliquot removed from the reaction
mixture showed triplet resonance at −129 ppm. De-
gassed water (100 mL) was added to quench residual
aluminum hydride. (Caution: Extreme care should
be taken when adding the first few milliliters of
water since quenching is highly exothermic and
H2 is evolved.) The ether layer was removed, and
the aqueous layer extracted with Et2O (150 mL,
100 mL). The organic layers were combined,
and the solvent removed in vacuo. The crude
product was purified by vacuum distillation 60◦C
(0.01 mmHg) to afford 5 (7.5 g, 70%) as colorless
liquid. (Caution: The product is pyrophoric and very
malodorous.)
4
122 mmol) in THF (150 mL), 2-i-PrC6H4Br (20.3 g,
102 mmol) was added. After 30 min, the Grignard
activated and the solution was refluxed for an ad-
ditional 2 h. The mixture was cooled to r.t. and
treated with ClP(NEt2)2 [31] (23.6 g, 112 mmol) and
washed with THF (5 mL). The solvent was removed
in vacuo, and the phosphine was extracted with hex-
anes (1 × 100 mL, 2 × 80 mL). The hexanes were
removed in vacuo leaving crude 2-i-PrC6H4P(NEt2)2
as a colorless liquid with 31P NMR singlet resonance
of 94 ppm. The crude solution of 2-i-PrC6H4P(NEt2)2
in CH2Cl2 (150 mL) was treated with gaseous dry
HCl, and the mixture became darker, cloudy, and
then clear. 31P NMR analysis of an aliquot removed
from the reaction mixture indicated two signals
at 221 ppm (PCl3) and 167 ppm (2-i-PrC6H4PCl2).
CH2Cl2 was evaporated in vacuo. The yellow solid
was extracted with toluene (3 × 60 mL), filtered,
and the solvent was removed in vacuo. The crude
product was purified by vacuum distillation 95◦C
(0.01 mmHg) to afford 3 (15.5 g, 69%) as a color-
less liquid.
31P NMR (162 MHz, CDCl3): δ −127 (t, JPH
=
203 Hz); 1H NMR (400 MHz, CDCl3): δ 7.53–7.48 (m,
1H), 7.34–7.26 (m, 2H), 7.13–7.06 (m, 1H), 3.96 (d,
3
JPH = 203 Hz, 2H), 3.28 (sept, JHH = 7 Hz, 1H),
3
1
1.29 (d, JHH = 7 Hz, 6H); 13C{ H} NMR (100 MHz,
CDCl3): δ 152 (d, JPC = 13 Hz), 136 (d, JPC = 7 Hz),
129, 128 (d, JPC = 8 Hz), 126 (d, JPC = 3 Hz), 125 (d,
JPC = 3Hz) 33 (d, JPC = 15 Hz), 24; MS (EI): m/z (%)
153, 152 [100, 11, M+], 138, 137 [33, 4, M-Me] 120,
119 [13, 4, M-PH2], 111, 110 [82, 9, M-C3H6], 91 [40,
C7H7].
1
31P NMR (162 MHz, CDCl3): δ 164 (s); H NMR
(400 MHz, CDCl3): δ 8.15–8.11 (m, 1H), 7.55–7.51 (m,
1H), 7.42–7.38 (m, 2H), 3.76 (sept, 3 JHH = 7 Hz, 1H),
1
1.36 (d, 3 JHH = 7 Hz, 6 H); 13C{ H} NMR (100 MHz,
CDCl3): δ 151.8 (d, JPC = 31 Hz), 137.2 (d, JPC
56 Hz), 133.1, 130.6 (d, JPC = 7 Hz), 127.2 (d, JPC
=
=
1 Hz), 125.7 (d, JPC = 34 Hz), 31.1 (d, JPC = 33 Hz),
24.4; MS (EI): m/z (%) 224, 222, 220 [7, 42, 66, M+],
209, 207, 202 [3, 15, 23, M-CH3], 187, 186, 185 [10,
9, 32, M-Cl]; Anal Calcd for C9H11Cl2P: C, 48.90; H,
5.02; found: C, 48.84; H, 5.02.
2-t-BuC6 H P H2 (6). Same procedure as de-
4
scribed above for 5. Used 4 (7.2 g, 31 mmol) and
LiAlH4 (0.873 g, 23 mmol). The crude product was
purified by vacuum distillation 60◦C (0.01 mmHg)
to afford title compound (4.17 g, 82%) as a colorless
liquid.
1
2-t-BuC6 H PCl2 (4). Same procedure as de-
31P NMR (162 MHz, CDCl3): δ −107 (t, JPH
=
4
scribed above for 3. Used 2-t-BuC6H4Br (8.47 g,
40 mmol), Mg (1.16 g, 48 mmol), and PCl(NEt3)2
(9.27 g, 44 mmol). The crude product was purified
by vacuum distillation 110◦C (0.01 mmHg) to afford
4 (7.4 g, 78%) as a colorless liquid.
202 Hz); 1H NMR (400 MHz, CDCl3): δ 7.58–7.53 (m,
1H), 7.47–7.42 (m, 1H), 7.29–7.23 (m, 1H), 7.11–7.05
1
(m, 1H), 4.21 (d, JPH = 203 Hz, 2H), 1.52 (s, 9H);
1
13C{ H} NMR (100 MHz, CDCl3): δ 154.3 (d, JPC
=
15 Hz), 140.0, 128.7, 127.8 (d, JPC = 17 Hz), 126.6 (d,
JPC = 5 Hz), 125.8, 36.9, 31.3 (d, JPC = 11 Hz); HRMS
calcd for C10H15P: 166.0911; found: 166.0908; MS
(EI): m/z (%) 167, 166 [7, 62, M+], 166 [100, M-H],
152, 151 [5, 56, M-Me], 134, 133 [3, 16, M-PH2], 110,
109 [13, 44, M-t-Bu], 57 [28, t-Bu].
1
31P NMR (121 MHz, CDCl3): δ 166 (s); H NMR
(400 MHz, CDCl3): δ 8.36–8.31 (m, 1H), 7.46–7.36 (m,
1
3H), 1.57 (s, 9H); 13C{ H} NMR (121 MHz, CDCl3): δ
153.5 (d, JPC = 28 Hz), 140.4 (d, JPC = 68 Hz), 134.9,
132,4, 127.5, 125.2, 37.0, 33.7; HRMS (EI): Cacld for
C10H13Cl2P 234.0132; found: 234.0131; MS (EI): m/z
(%) 236, 235, 234 [43, 24, 68, M+], 221, 220, 219
[18, 4, 27, M-Me], 201, 200, 199 [14, 10, 45, M-Cl],
147 [100, M-CH5Cl2], 133 [22, M-PCl2]; Anal Calcd
for C10H13Cl2P: C, 51.09; H, 5.57; found: C, 50.97; H,
5.60.
2-i-PrC6 H P(Si Me3) (7). To a cooled solution
4
2
(−78◦C) of 5 (7.0 g, 46 mmol) in THF (100 mL),
MeLi in Et2O (1.45 M, 70 mL, 101 mmol) was added.
The reaction mixture was warmed to room tem-
perature and stirred for 1 h whereafter the solu-
tion was cooled (−78◦C) and treated with Me3SiCl
(13.5 mL, 106 mmol). 31P NMR analysis of an
aliquot removed from the reaction mixture revealed
2-i-PrC6 H P H2 (5). To a cooled (−78◦C) solu-
4
tion of LiAlH4 (2.1 g, 56 mmol) in Et2O (300 mL), a
Heteroatom Chemistry DOI 10.1002/hc

Synthesis of Functional Phosphines with Ortho-Substituted Aryl Groups 269
[3] See, for example: (a) Mizuhata, T.; Sasomori, T.
the presence of 2-i-PrC6H4P(SiMe3)2 at −153 ppm.
Chem Rev 2009, 109, 3479–3511; (b) Rivard E.;
Power, P. P. Dalton Trans 2008, 4336–4343; (c)
Sasomori, T.; Tokitoh, N. Dalton Trans 2008, 1395–
1408; (d) Shah, S.; Protasiewicz, J. D. Coord Chem
Rev 2000, 181–201; (e) Robinson, G. H. Acc Chem
Res 1999, 32, 773–782.
Often, after the first lithiation a mixture of 2-i-
PrC6H4P(SiMe3)2 and 2-i-PrC6H4PH(SiMe3) was ob-
served. In this instance, the reaction mixture was
relithiated (20 mL) and silylated (3.6 mL) follow-
ing the above-mentioned procedure. Typically, af-
ter one relithiation 7 was formed quantitatively (31P
NMR spectroscopy). The solvent was removed in
vacuo. The yellow solid was extracted with hex-
anes (2 × 100 mL, 50 mL), filtered, and the sol-
vent was removed. The crude product was puri-
fied by vacuum distillation (113◦C, 0.01 mmHg), af-
fording title compound (6.6 g, 48%) as a colorless
liquid.
[4] Fritz, G.; Scheer, P. Chem Rev 2000, 100, 3341–3401.
[5] Hayashi, M. Chem Rec 2009, 9, 236–245.
[6] Hayashi, M.; Matsuura, Y.; Watanabe, Y. Tetrahe-
dron Lett 2004, 45, 9167–9169.
[7] Hayashi, M.; Matsuura, Y.; Watanabe, Y. Tetrahe-
dron Lett 2005, 46, 5135–5138.
[8] Hayashi, M.; Matsuura, Y.; Kurihara, K.; Maeda, D.;
Nishimura, Y.; Morita, E.; Okasaka, M. Chem Lett
2007, 36, 634–635.
[9] Hayashi, M.; Matsuura, Y.; Watanabe, Y. J Org Chem
2006, 71, 9248–9251.
[10] Trepohl, V. T.; Oestreich, M. Chem Commun 2007,
3300–3302.
[11] Trepohl, V. T.; Mori, S.; Itami, K.; Oestreich, M. Org
Lett 2009, 11, 1091–1094.
[12] Couret, C.; Escudie, J.; Satge, J.; Anh, N. T.; Soussan,
G. J Organomet Chem 1975, 91, 11–30.
[13] Hayashi, M.; Matsuura, Y.; Nishimura, Y.; Yamasaki,
T.; Imai, Y.; Watanabe, Y. J Org Chem 2007, 72, 7798–
7800.
31P NMR (162 MHz, CDCl3): δ −153 (s); 1H NMR
(400 MHz, CDCl3): δ 7.50–7.46 (m, 1H), 7.34–7.25
3
(m, 2H), 7.10–7.04 (m, 1H), 3.98 (sept, JHH = 7 Hz,
3
1H), 1.25 (d, JHH = 7 Hz, 6H), 0.30 (s, 9H), 0.28
1
(s, 9H); 13C{ H} NMR (100 MHz, CDCl3): δ 155.6
(d, JPC = 21.5 Hz), 138.5 (d, JPC = 6 Hz), 130.3 (d,
JPC = 11.5 Hz), 128.1, 125.6 (d, JPC = 6 Hz), 124.9,
32.2 (d, JPC = 24 Hz), 23.9, 1.6, 1.4; HRMS calcd for
C13H29PSi2: 296.1546; found: 296.1547; MS (EI): m/z
(%) 297, 296 [6, 21, M+], 282, 281 [2, 6, M-Me], 224,
223 [4, 10, M-SiMe3], 75, 74, 73 [4, 8, 100, SiMe3];
Anal Calcd for C15H29PSi2: C, 60.76; H, 9.86; found:
C, 60.42; H, 9.84.
[14] Matsuura, Y.; Yamasaki, T.; Watanabe, Y.; Hayashi,
M. Tetrahedron: Asymmetry 2007, 18, 2129–2132.
[15] Kolodiazhnyi, O. I.; Guliaiko, I. V.; Kolodiazhna, A.
O. Tetrahedron Lett 2004, 45, 6955–6957.
[16] Tunney, S. E.; Stille, J. K. J Org Chem 1987, 52, 748–
753.
[17] Kazankova, M. A.; Chirkov, E. A.; Kochetkov, A. N.;
Efimova, I. V.; Beletskaya, I. P. Tetrahedron Lett
1998, 40, 573–576.
[18] Chan, V. S.; Bergman, R. G.; Toste, F. D. J Am Chem
Soc 2007, 129, 15122–15123.
[19] Smit, C. N.; Vanderknaap, T. A.; Bickelhaupt, F.
Tetrahedron Lett 1983, 24, 2031–2034.
[20] Yam, M.; Chong, J. H.; Tsang, C. W.; Patrick, B. O.;
Lam, A. E.; Gates, D. P. Inorg Chem 2006, 45, 5225–
5234.
2-t-BuC6 H P(Si Me3)2 (8). Same procedure as
4
described above for 7. Used 6 (4.1 g, 25 mmol), MeLi
in Et2O (1.5 M, 33 mL, 50 mmol) and TMSCl (6.3 mL,
50 mmol). The crude product was purified by vac-
uum distillation (130◦C, 0.01 mmHg) to afford title
compound (5.65 g, 72%) as a colorless liquid.
31P NMR (162 MHz, CDCl3): δ −134 (s); 1H NMR
(400 MHz, CDCl3): δ 7.57–7.53 (m, 1H), 7.48–7.43
(m, 1H), 7.25–7.19 (m, 1H), 7.09–7.03 (m, 1H), 1.62
[21] Bates, J. I.; Dugal-Tessier, J.; Gates, D. P. Dalton
Trans 2010, 39, 3151–3159.
(d, JPH = 1 Hz 9H), 0.29 (s, 9H), 0.28 (s, 9H);
[22] See, for example: (a) Le Floch, P. Coord Chem Rev
2006, 250, 627–681; (b) Takita, R.; Takada, Y.; Jensen,
R. S.; Okazaki, M.; Ozawa, F. Organometallics 2008,
27, 6279–6285; (c) Hayashi, A.; Okazaki, M.; Ozawa,
F. Orgaometallics 2007, 26, 5246–5249; (d) De-
schamps, B.; Le Goff, X.; Ricard, L.; Le Floch, P.
Heteroatom Chem 2007, 18, 363–371; (e) Smith,
R. C.; Protasiewicz, J. D. J Am Chem Soc 2004, 126,
2268–2269; (f) Ionkin, A.; Marshal, W. Chem Com-
mun 2003, 710–711; (g) Daugulis, O.; Brookhart, M.;
White, P. S. Organometallics 2002, 21, 5935–5943; (h)
Ozawa, F.; Okamota, H.; Kawagishi, S.; Yamamoto,
S.; Minami, T.; Yoshifuji, M. J Am Chem Soc 2002,
124, 10968–10969.
1
13C{ H} NMR (100 MHz, CDCl3): δ 156.7 (d, JPC
=
18 Hz), 142.6 (d, JPC = 6 Hz), 130.8 (d, JPC = 22 Hz),
127.7, 126.6 (d, JPC = 8 Hz), 124.6, 37.4, 32.0 (d,
JPC = 11 Hz), 1.9, 1.8; HRMS calcd for C16H31PSi2:
310.1702; Found: 310.1701; MS (EI): m/z (EI) 312,
311, 310 [2, 9, 32, M+], 296, 295 [3, 9, M-Me], 239,
238, 237 [4, 10, 49, M-SiMe3], 74, 73 [7, 100, SiMe3];
Anal Calcd for C16H31PSi2: C, 61.88; H, 10.06; found:
C, 61.90; H, 10.09.
[23] Tsang, C. W.; Yam, M.; Gates, D. P. J Am Chem Soc
2003, 125, 1480–1481.
REFERENCES
[24] Tsang, C. W.; Rohrick, C. A.; Saini, T. S.; Patrick,
B. O.; Gates, D. P. Organometallics 2004, 23, 5913–
5923.
[25] Noonan, K. J. T.; Gillon, B. H.; Cappello, V.; Gates,
D. P. J Am Chem Soc 2008, 130, 12876–12877.
[1] Klebach, T. C.; Lourens, R.; Bickelhaupt, F. J Am
Chem Soc 1978, 100, 4886–4888.
[2] Yoshifuji, M.; Shima, I.; Inamoto, N.; Hirotsu, K.;
Higuchi, T. J Am Chem Soc 1981, 103, 4587–
4589.
Heteroatom Chemistry DOI 10.1002/hc

270 Dugal-Tessier et al.
[26] Gillon, B. H.; Patrick, B. O.; Gates, D. P. Chem Com-
mun 2008, 2161–2163.
[27] Tsang, C. W.; Baharloo, B.; Riendl, D.; Yam, M.;
Gates, D. P. Angew Chem, Int Ed 2004, 43, 5682–
5685.
[30] Fey, N.; Howell, J. A. S.; Lovatt, J. D.; Yates, P. C.;
Cunningham, D.; McArdle, P.; Gottlieb, H. E.; Coles,
S. J. Dalton Trans 2006, 5464–5475.
[31] King, R. B.; Sundaram, P. M. J Org Chem 1984, 49,
1784–1789.
[28] Dugal-Tessier, J.; Dake, G. R.; Gates, D. P. Angew
Chem, Int Ed 2008, 47, 8064–8067.
[29] Dugal-Tessier, J.; Dake, G. R.; Gates, D. P.
Organometallics 2007, 26, 6481–6486.
[32] Becker, G.; Mundt, O.; Rossler, M.; Schneider, E.
Z Anorg Allg Chem 1978, 443, 42–52.
[33] Han, L. B.; Tilley, T. D. J Am Chem Soc 2006, 128,
13698–13699.
Heteroatom Chemistry DOI 10.1002/hc