Synthesis, structure, and application of [PhNMe2H][B{C6F4C(C6F5) 2F}4]

Article abstract of DOI:10.1021/om001080i

The new perfluorinated tetraaryl borate [B{C₆F₄C(C₆F₅)₂F} ₄]^- (3) has been prepared and characterized. The X-ray structural analysis of [C₆H₅N(H)(CH₃) ₂][3] confirms the tetrahedral geometry about the boron. The performance of 3 as a weakly coordinating anion in ethylene polymerization was evaluated and compared with that of B(C₆F₅)₄ ^- and B(3,5-(CF₃)₂C₆H₃) ₄^-. The stability of 3 throughout polymerization was evaluated by analyzing anion residues in a polymer sample using mass spectroscopy.

Full text of DOI:10.1021/om001080i

Organometallics 2001, 20, 2417-2420
2417
Syn th esis, Str u ctu r e, a n d Ap p lica tion of
[P h NMe2H][B{C6F 4C(C6F 5)2F }4]
George Rodriguez* and Patrick Brant
Baytown Polymers Center, ExxonMobil, Baytown, Texas 77521
Received December 22, 2000
Sch em e 1
Summary: The new perfluorinated tetraaryl borate
[B{C6F4C(C6F5)2F}4]- (3) has been prepared and char-
acterized. The X-ray structural analysis of [C6H5N(H)-
(CH3)2][3] confirms the tetrahedral geometry about the
boron. The performance of 3 as a weakly coordinating
anion in ethylene polymerization was evaluated and
-
compared with that of B(C6F5)4- and B(3,5-(CF3)2C6H3)4
.
The stability of 3 throughout polymerization was evalu-
ated by analyzing anion residues in a polymer sample
using mass spectroscopy.
In tr od u ction
Weakly coordinating anions (WCAs) are used by
investigators of the academic and industrial sectors for
a wide variety of applications.1 Of the many WCAs
described in the scientific and patent literature, fluori-
nated tetraaryl borates (B[Arf]4-) are of considerable
interest to those working in olefin polymerization. The
increasing number of publications in this area is evi-
dence of the growing interest in this type of WCA.2,3
Increasing the diversity of WCAs is the first step
toward a better understanding of these compounds.
More specifically, a large repertoire of structurally and
electronically diverse WCAs will provide the information
necessary to determine what features need to be ma-
nipulated in order to improve polymerization perfor-
mance.2 The most common method to prepare fluori-
nated tetraaryl borates is to react a metalated fluoroaryl
(Arf-M; M ) Li, MgBr, etc.) with a boron trihalide.
Therefore, the synthesis of new fluorinated aryls that
are easily metalated for subsequent salt metathesis will
facilitate the preparation of novel WCAs. The results
presented by Marks lend credence to this point of
view.3,4 In this connection, the synthesis of 4-H-C6F4C-
(C6F5)2F is presented along with its use in making
[B{C6F4C(C6F5)2F}4]- (3) as an N,N-dimethylanilinium
(DMAH) salt. The solid state structure of [DMAH][3]
is discussed. Additionally, the performance of this new
WCA in ethylene polymerization is presented and
- 5,6
compared against B[C6F5]4- and B[3,5-(CF3)2C6H3]4
.
Resu lts a n d Discu ssion
Syn th esis of [P h NMe2H][B{C6F 4C(C6F 5)2F }4]. The
synthesis of [PhNMe2H][B{C6F4C(C6F5)2F}4] (Ph )
-C6H5; Me ) -CH3) is depicted in Scheme 1. Deca-
fluorobenzophenone was added to a cold (-78 °C) diethyl
ether solution of 4-H-C6F4Li.4 The resulting mixture was
quenched with an aqueous solution of NH4Cl to afford
the corresponding alcohol HC6F4C(C6F5)2OH (1) as a
white solid in excellent yield. This procedure is similar
to the one used to prepare (C6F5)3COH7 and HOC(CF3)2-
(4-Si(i-Pr)3-2,6-C6H2(CF3)2).8 Replacing the -OH group
in 1 with -F was readily accomplished using Olah’s
reagent9 and results in HC6F4C(C6F5)2F (2). After
purification via column chromatography, compound 2
was used to prepare [PhNMe2H][3] in a one-pot proce-
dure using standard methodology (see Scheme 1 and
Experimental Section).4,5 Compound [PhNMe2H][3] was
characterized by 1H, 13C, 11B, and 19F nuclear magnetic
resonance (NMR), elemental analysis, and X-ray crys-
tallography.
(1) (a) Reed, C. A. Acc. Chem. Res.1998, 31, 133. (b) Strauss, S. H.
Chem. Rev. 1993, 93, 927. (c) Strauss, S. H. Chemtracts: Inorg. Chem.
1994, 6, 1. (d) Baur, R.; Macholdt, H. DE Patent 4142541. (e) Fisk, T.
E.; Tucher, C. J . US Patent 5000873. (f) Waller, F. J .; Barrett, A. G.
M.; Braddock, D. C.; Rampasad, D.; McKinnell, R. M.; White, A. J . P.;
Williams, D. J .; Ducray, R. J . Org. Chem. 1999, 64, 2910. (g) Xie. Z.;
Bau, R.; Reed, C. A. Inorg. Chem. 1995, 34, 5403.
(2) An excellent review on the field: Chen, Y.; Marks, T. J . Chem.
Rev. 2000, 100, 1391. (b) Bohnen, H.; Achermann, J . W. O. Patent 99/
43865. (c) Williams, V. C.; Irvine, G. J .; Piers, W. E.; Li, Z.; Collins, S.;
Clegg, W.; Elsegood, M. R. J .; Marder, T. B. Organometallics 2000,
19, 1619. (d) LaPointe, R. E.; Roof, G. R.; Abboud, K. A.; Klosin, J . J .
Am. Chem. Soc. 2000, 122, 9560. (e) Lanza, G.; Fragala, I. L.; Marks,
T. J . J . Am. Chem. Soc. 2000, 122, 12764. (f) Zhou, Lancaster, S. J .;
Walker, D. A.; Beck, S. Thornton-Pett, M. Bochmann, M. J . Am. Chem.
Soc. 2001, 123, 223.
(5) (a) Turner, H. W. European Patent No. 277,0041998. (b) Hlatky,
G. G.; Upton, D. J .; Turner, H. W. U.S. Patent Appl. P 459921, 1990.
(6) (a) Nishida, H.; Takada, N.; Yoshimura, M.; Sonoda, T.; Koba-
yashi, H. Bull. Chem. Soc. J pn. 1984, 57, 2600. (b) Brookhart, M.;
Grant, B.; Volpe, A. F. Organometallics 1992, 11, 3920.
(7) Filler, R.; Wang, C.-S.; McKinney, M. A.; Miller, F. N. J . Am.
Chem. Soc. 1967, 89, 1026.
(3) Aluminates are also used in this context: (a) Chen, Y.; Marks,
T. J . W. O. Patent 98/07515. (b) Elder, M. J .; Leyder, F. European
Patent 0 573 403 A2. (c) Sun, Y.; Metz, M. V.; Stern, C. L.; Marks, T.
J . Organometallics 2000, 19, 1625 (and references therein). (d) Chen,
E. Y.-X.; Abboud, K. A. Organometallics 2000, 19, 5541.
(8) Barbarich, T. J .; Runthner, C. D.; Miller, S. M.; Anderson, O.
P.; Strauss, S. H. J . Am. Chem. Soc. 1999, 121, 4280.
(4) Chen, Y.-X.; Metz, M. V.; Stern C. L.; Marks J . Am. Chem. Soc.
1998, 120, 6287.
(9) Olah, G. A.; Welch, J . T.; Vankar, Y. D.; Nojima, M.; Kerekes,
I.; Olah, J . A. J . Org. Chem. 1979, 44, 3872.
10.1021/om001080i CCC: $20.00 © 2001 American Chemical Society
Publication on Web 04/18/2001

2418 Organometallics, Vol. 20, No. 11, 2001
Ta ble 1. Resu lts of Eth ylen e P olym er iza tion Rea ction sa
Notes
catalyst
(mg)
time
(min)
activity
(g/mmol min)
d
d
d
run
anionb
yield (g)
Mn (10-3
)
Mw (10-3
)
Mw/Mn
1
2
3
4
5
6
7
8
3
3
3
3
33.6
32.0
31.9
31.4
48.2
45.8
30.7
38.7
20
20
30
40
20
20
30
20
9.0
7.4
6.6
5.7
6.2
6.9
20
15
12
10
74
51
49
110
114
109
103
111
131
104
94
197
228
234
227
247
1.77
2.06
1.92
1.80
1.99
2.14
2.20
2.22
12.1
17.6
27.6
34.6
22.4
15.8
- c
B(Arf)4- c
B(Arf)4
-
B(C6F5)4-
B(C6F5)4
a
b
Catalyst activations and polymerizations were performed in toluene. Cationic activator for all runs was N,N′-dimethylanilinium.
c Arf ) -(3,5-(CF3)2C6H3)4. Determined by GPC.
d
structure.10 Within the 19F NMR time scale, rapid
rotation about the BC6F5-C(F)C6F5 bond is indicated
by the equivalent ortho fluorines on the tetrafluoro-
phenyl rings. The corresponding meta fluorines are
equivalent as well. Similarly, rapid rotation about the
BC6F5C(F)-C6F5 bonds readily explains the three sig-
nals attributed to the fluorines on the pentafluorophenyl
rings.
Ap p lica tion of [P h NMe2H][B{C6F 4C(C6F 5)2F }4].
Combining L-NiMe2 (L ) (2,6-C6H3(i-Pr)2)NdC(Me)C-
(Me)dN(2,6-C6H3(i-Pr)2), Me ) CH3) with [PhNMe2H]-
[3] in toluene resulted in a deep purple solution. This
is the same color observed when L-NiMe2 is activated
with either [PhNMe2H][B(3,5-(CF3)2C6H3)4] or [PhNMe2-
H][B(C6F5)4]. On the basis of the 19F NMR spectrum of
this solution, it is clear that 3 remains intact after acti-
vation. Table 1 shows the results of ethylene polymer-
ization reactions using [L-NiMe][3]. Comparative polym-
erization reactions using [PhNMe2H][B(3,5-(CF3)2C6-
H3)4]11 and [PhNMe2H][B(C6F5)4]2,5,11 as cocatalysts are
F igu r e 1. ORTEP diagram of 3. Thermal ellipsoids are
shown at the 50% level.
shown in Table 1 as well. On the basis of these results
it may be concluded that the molecular weights of the
polymers prepared with [L-NiMe][B(C6F5)4] and [L-NiMe]-
[B(3,5-(CF3)2C6H3)4] are higher than those made with
[L-NiMe][3]. Additionally, the activities of the latter
system were lower than those obtained with the first
two combinations. The reason the first two catalyst
systems and [L-NiMe][3] behave so differently with
respect to molecular weight capability and activity is
unclear at this point.
Attempts to obtain a group 4 metallocene cation
stabilized with 3 were unsuccessful. Combining a vari-
ety of dimethyl zirconocenes or hafnocenes with [PhN-
Me2H][3] in toluene resulted in black solutions and
precipitates. The 1H and 19F NMR spectra of these
mixtures indicated the presence of numerous indiscern-
ible byproducts. Similar results were observed when the
activation reactions were done in the presence of olefin
(octene or ethylene). When the activation step was
performed in THF-d8, stable complexes were obtained.
These complexes are most likely the metallocenium-
THF adducts.12 These metallocene adducts did not
polymerized R olefins. In this context, it is worth noting
that activation of most dimethyl zirconocenes or hafno-
The one-pot approach used here is noteworthy since
it is atypical in this context.2 The lithium salts of
tetraaryl borates are typically isolated prior to the
reaction with the desired ammonium chloride (e.g.,
PhNMe2HCl). However, attempts to isolate the lithium
salt of 3 resulted in a dark green material. No charac-
terization of this green material was attempted. When
PhNMe2HCl is added to the lithium salt prepared in
situ, the product was isolated using standard workup
procedures.
Str u ctu r e of [P h NMe2H][B{C6F 4C(C6F 5)2F }4]. The
solid state structure of [PhNMe2H][3] was determined
by single-crystal X-ray crystallography (Figure 1). Com-
pound [PhNMe2H][3] crystallizes in the Pbcn space
group with boron lying on a special position. The
PhNMe2H cation was disordered over two sites. Despite
the cation disorder, the anion refined well enough to
discuss connectivity and ligand orientation. The boron
atom adopts a tetrahedral geometry. The B-C distances
(1.640(10) Å, 1.651(10) Å) and C-B-C angles (102.0°,
-
114.3°) are similar to those found in B(C6F5)4 and
B(C6F4-SiR3)-.4 The similarities between these metric
-
parameters vis-a`-vis those of B(C6F5)4 and B(C6F4-
(10) For 19F NMR discussion see: Hudlicky, M.; Pavlath, A. E.
Chemistry of Organic Fluorine Compounds II, A Critical Review; ACS
Monograph 187; American Chemical Society: Washington, DC, 1995;
pp 1037-1088.
(11) (a) J ohnson, L. K.; Killian, C. M.; Brookhart, M. J . Am. Chem.
Soc. 1995, 117, 6414. (b) Stefan, M.; J ohnson, L. K.; Wang, L.;
Brookhart, M. J . Am. Chem. Soc. 1998, 120, 888.
SiR3)- allow us to conclude that the molecular struc-
tures of tetraaryl borates are not affected by large
substituents on the para positions. All of the C-F
distances and angles are unexceptional.
The 19F NMR spectrum of [PhNMe2H][3] in CH2Cl2
at room temperature is consistent with a fluxional
(12) Polymerization with THF adduct: J ordan, R. F. J . Am. Chem.
Soc. 1986, 108, 7410.

Notes
Organometallics, Vol. 20, No. 11, 2001 2419
afford the product as a white crystalline solid: yield 11.60 g
1
(94%). H NMR (CDCl3, 25°): δ 7.08 (m, 1H), 3.72 (t, 1H). 13C
NMR (CDCl3, 25 °C): δ 146.5 (dm, J C-F ) 250 Hz), 145.3 (dm,
J C-F ) 250 Hz), 144.4 (dm, J C-F ) 250 Hz), 139.8 (dm, J C-F
)
250 Hz), 138.5 (dm, J C-F ) 250 Hz), 121.5 (t, J C-F ) 10 Hz),
116.5 (bs), 106.9 (t, J C-F ) 22 Hz), 74.0 (s). 19F NMR (CDCl3,
25 °C): δ 137.9 (m, 2F), 140.0 (d, 4F), 141.2 (m, 2F), 152.3 (t,
2F), 161.4 (m, 4F).
HC6F 4C(C6F 5)2F (2). In a polyethylene bottle, HC6F4C-
(C6F5)2OH (0.650 g, 1.3 mmol) was suspended in 7.0 g of
pyridinium polyhydrogenfluoride (Olah’s reagent). The sus-
pension was stirred for 14 h. The product was extracted with
pentane. Evaporation of the pentane afforded the product as
a pale yellow crystalline solid: yield 0.490 g (75%). Analytically
pure crystals were obtained by recrystallization from diethyl
ether. 13C NMR (CDCl3, 25 °C): δ 146.4 (dm, J C-F 264 Hz),
145.0 (dm, J C-F 257 Hz), 144.4 (dm, J C-F 254 Hz), 142.3 (dm,
J C-F 264 Hz), 137.0 (dm, J C-F 247 Hz), 117.8 (m), 112.9 (m),
108.3 (t, J C-F 22 Hz), 89.0 (J C-F 191 Hz). 19F NMR (CDCl3, 25
C): δ -127.9 (m, 1F), -137.4 (m, 2F), -139.6 (m, 4F), -140.2
F igu r e 2. Mass spectra of 3.
cenes in toluene with [PhNMe2H][B(C6F5)4] typically
results in clear, colored solution (see Experimental
Section).
Sta bility of 3. The narrow polydispersities obtained
for runs 1-4 indicate that 3 remains intact throughout
polymerization. In this connection a polymer sample
from run 4 was analyzed using time-of-flight secondary
ion mass spectroscopy (ToF-SIMS). The use of mass
spectroscopy in this context has been reported sepa-
rately by Erker13 and Brant et al.14
(m, 2F), -149.9 (m, 2F), -160.7 (m, 4F). Anal. Calcd for C19
HF19: C, 44.38; H, 0.19. Found: C, 43.74; H, <0.5.
-
[P h NMe2H][B{C6F 4C(C6F 5)2F }4]. HC6F4C(C6F5)2F (2.058
g, 4.0 mmol) was dissolved in 100 mL of diethyl ether, chilled
to -78 °C, and treated with a BuLi solution in hexane (2.5
mL, 4.0 mmol). The reaction was allowed to stir for 45 min at
-78 °C. BCl3 in hexane (1.0 mL, 1.0 mmol, 1.6 M) was added
and stirred for 20 min. The cold bath was removed, and the
reaction was stirred for 1 h. At this point there was a white
precipitate suspended in a pale pink solution. A methyl-
enechloride solution of C6H5N(CH3)2HCl (0.158 g, 1.0 mmol)
was added, and the reaction stirred for 1 h. The white LiCl
precipitate was removed by filtration, and the solvent evapo-
rated. This afforded a pale pink semisolid. Triturating the pink
material with pentane afforded a light blue solid: yield 2.001
g (91%). Analytically pure crystals were obtained by permitting
pentane to slowly diffuse into a glyme (DME) solution. This
afforded clear, colorless crystals which, by 1H NMR and
elemental analysis, were found to contain two molecules of
DME. 13C NMR (THF-d8, 25 °C): δ 149.6 (dm, J C-F ) 245 Hz),
145.9 (dm, J C-F ) 258 Hz), 144.5 (dm, J C-F ) 251 Hz), 145.2
(s), 138.9 (dm, J C-F ) 253 Hz), 134.1 (b), 130.7 (s), 129.4 (s),
121.7 (s), 114.8 (m), 113.4 (m), 109.9 (t, J C-F 25 Hz), 90.1 (t,
J C-F ) 188 Hz), 46.4 (s). 19F NMR (CDCl3, 25 C): δ -126.2
(m, 1F), -131.8 (m, 2F), -139.8 (m, 4F), -145.1 (m, 2F),
-151.7 (m, 2F), -161.8 (m, 4F). 11B NMR (THF-d8, 25 °C): δ
-16.2. Anal. Calcd for C92H28BF60NO4: C, 46.75; H, 1.20.
Found: C, 46.19, 46.34; H, 1.22, 1.18.
The result of this experiment is depicted in Figure 2.
The parent peak is clearly seen at 2063 atomic mass
units. Due to the severe conditions the anion is subjected
to during the experiment (see Experimental Section),
the two smaller features at higher atomic mass units
are likely products generated at this stage. For example,
the cluster at 2083 amu is consistent with the addition
of HF (20 amu) to one of the aromatic rings. One
possible hydrogen source is the countercation. Another
possibility is the toluene used to prepare the sample (see
Experimental Section).
-
In summary, the new anion B[C6F4C(C6F5)2F]4 (3)
is readily accessible by the application of a straightfor-
ward synthetic methodology. The tetrahedral geometry
about the boron has been corroborated by single-crystal
X-ray crystallography. Although [L-NiMe][B(C6F5)4] and
[L-NiMe][B(3,5-(CF3)2C6H3)4] exhibit higher molecular
weight capabilities and catalyst activities than [L-NiMe]-
[3], it has been demonstrated that 3 is an effective
weakly coordinating anion in ethylene polymerization
reactions.
Exp er im en ta l Section
Activa tion Exp er im en ts. (a) Tetrahydrofuran: To a THF-
d8 solution of bis(pentamethylcyclopentadienyl)hafniumdimethyl
(22 mg, 0.05 mmol) was added a THF-d8 solution of [PhNMe2H]-
[B(C6F5)4] (40 mg, 0.05 mmol). A pale yellow solution resulted.
Gen er a l Con sid er a tion s. All manipulations were carried
out using either high-vacuum or glovebox techniques as
described previously.15 All solvents were dried with anhydrous
alumina. Elemental analyses were carried out by Galbraith
Laboratory. CFCl3 (0 ppm) was used as internal reference in
the 19F NMR experiments.
HC6F 4C(C6F 5)2OH (1). HC6F4Br (5.496 g, 24 mmol) was
dissolved in 100 mL of diethyl ether. The solution was chilled
to -78 °C and treated with BuLi (15.0 mL, 24 mmol, 1.6 M).
The reaction was allowed to stir for 2 h. To the resulting
solution was added a solution of decafluorobenzophenone
(8.691 g, 24 mmol). The reaction was allowed to stir for an
additional 0.5 h, then quenched with 4 M NH4Cl(aq). The
mixture was allowed to reach room temperature. The organic
layer was separated, washed with brine, and dried over
MgSO4. The MgSO4 was removed by filtration, and the solvent
was evaporated. The product solidifies after several hours to
1
The H NMR spectrum is consistent with the presence of the
metallocenium-THF adduct.12 A similar result was obtained
when the activation was performed with [C6H5N(CH3)2H]B-
[C6F4C(C6F5)2F]4 (same molar scale). The 19F NMR spectrum
of this last combination is identical to that of the starting
material (i.e., [C6H5N(CH3)2H]B[C6F4C(C6F5)2F]4 in THF-d8,
see previous paragraph). Analogous results were obtained with
bis(cyclopentadienyl)zirconiumdimethyl. (b) Toluene: To a tol-
uene-d8 solution of bis(pentamethylcyclopentadienyl)hafnium-
dimethyl (23 mg, 0.05 mmol) was added a toluene-d8 solution
of [C6H5N(CH3)2H][B{C6F4C(C6F5)2F}4] (112 mg, 0.05 mmol).
This combination resulted in a black solution and black
precipitate. The 1H NMR spectrum of this combination con-
sisted of numerous broad peaks.
(13) Erker, T. G.; Luftman, K. H.; Frohlich, R.; Kotila, S. Angew.
Chem., Int. Ed. Engl. 1995, 1755.
(14) Brant, P.; Wu, K.-J . J . Matt. Sci. Lett. 2000, 189.
(15) Burger, B. J .; Bercaw, J . E. In Experimental Organometallic
Chemistry; Wayda, A. L., Darensbourg, M. Y., Eds.; ACS Symp. Ser.
353; American Chemical Society: Washington, D.C., 1987.
Ba tch P olym er iza tion Rea ction s. Ethylene polymeriza-
tion reactions were carried out in a well-stirred batch reactor
equipped to perform coordination polymerization in the pres-
ence of an inert hydrocarbon (toluene) solvent at pressures up
to 500 psi and temperatures up to 150 °C. Ethylene was

2420 Organometallics, Vol. 20, No. 11, 2001
Notes
Ta ble 2. Cr ysta l Da ta a n d Str u ctu r e Refin em en t
for [P h N(CH3)2H][3]
continuously fed into the reactor to keep the vapor pressure
constant at 80 psi during the polymerization reactions. In all
experiments, the reactor temperature was kept constant at
80 °C by electronically controlling the flow of steam through
the reactor jacket. Typically, the catalyst solution (catalyst and
activator dissolved in 40 mL of toluene) was first prepared
inside a nitrogen purge box, transferred to a glass vial, capped,
sealed, and brought out of the box. Toluene (400 mL) was then
fed into the dry reactor from a 20 L toluene tank. The catalyst
solution was transferred into the reactor via a cannula. The
reactor was closed and heated to 80 °C. The reactor was
pressurized with ethylene and maintained at constant pres-
sure throughout the polymerization. Polymerization began
immediately upon addition of ethylene and was allowed to
continue under controlled temperature and pressure. After the
indicated times (Table 1), the reactor was allowed to reach
room temperature and depressurized by venting. The polym-
erization solution was poured into methanol to induce pre-
cipitation. The amorphous polymer was collected and allowed
to dry over 16 h. The polymer was dried further under vacuum.
P olym er Molecu la r Weigh t Deter m in a tion . GPC mea-
surements were carried out using a Waters 150C GPC
empirical formula
temperature
wavelength
C84H12BF60N
228(2) K
0.71073 Å
cryst syst
orthorhombic
space group
Pbcn
unit cell dimens
a ) 16.612(7) Å, R ) 90°
b ) 18.808(7) Å, â ) 90°
c ) 26.104(10) Å, γ ) 90°
8156(5) Å3, 4
volume, Z
density (calcd)
abs coeff
1.780 Mg/m3
0.201 mm-1
F(000)
4272
cryst size
θ range for data collected
limiting indices
0.20 × 0.20 × 0.10
1.56-28.46°
-21e h e 21, -10 e k e 24,
-30 e l e 33
45 142
no. of reflns
no. of ind reflns
9466 (Rint ) 0.2088)
completeness to θ ) 28.46°
max. and min. transmn
refinement method
no. of data/restraints/params
final R indices [I>2σ(I)]
extinction coeff
91.9%
0.9802 and 0.9610
full-matrix least-squares on F2
9466/0/643
equipped with
a differential refractive index detector, a
R1 ) 0.0878, wR2 ) 0.2180
0.0014(2)
Precision Detector light scattering (LS) detector, and a Vis-
cotek high temperature differential viscometer for accurate
molecular weight measurement. Three Polymer Laboratory
Mixed B (10 µm spheres) type columns are used. Polymer
samples were dissolved in 1,2,4-trichlorobenzene (TCB) at 135
°C and run at a flow rate of 0.5 mL/min. In all cases the
injected volume was 300 µL.
The GPC is routinely calibrated with a series of polymers
of known molecular weights and intrinsic viscosities (a com-
bination of National Bureau of Standards polyethylenes and
narrow polystyrene standards).
largest diff peak and hole
1.781 and -0.350 e Å-3
ary ion mass spectrometry (ToF-SIMS) analysis and a nitrogen
laser (λ ) 337 nm) for laser desorption mass spectrometry
(LDMS) analysis. The ToF-SIMS spectrum was obtained
operating the ion gun at 15 keV and 600 pA. Mass calibration
was carried out using a variety of known standards.
The resin sample was prepared using the following proto-
cols: polymer resin (∼30 mg) was placed in a glass vial
containing 10 mL of toluene and the mixture heated to 90 °C.
After extraction for 3 min, approximately 1 µL of the solution
is deposited on a sample substrate (clean Si wafer). The solvent
was evaporated in air, and the wafer with extracted material
was then inserted into the instrument for mass spectral
analysis.
X-r a y Str u ctu r e Deter m in a tion . Crystallographic data
for [C6H5N(CH3)2H]B[C6F4C(C6F5)2F]4 were collected on
a
Bruker P4 diffractometer equipped with a SMART CCD
detector. The structure was solved using direct methods and
standard difference map techniques and was refined by full-
matrix least-squares procedures using SHELXTL.16 Systematic
absences were consistent uniquely with Pbcn (No. 60). The
dimethylanilinium counterion was disordered about an inver-
sion center, and the disorder was modeled accordingly. Hy-
drogen atoms on carbon were included in calculated positions.
Crystal data, data collection, and refinement parameters are
summarized in Table 2.
Ack n ow led gm en t. We thank Mary Teel Castillo
and Ray Chen, who performed the polymerization
reactions. Ged Parkin (Columbia University) is grate-
fully acknowledged for performing the X-ray diffraction
study of [C6H5N(CH3)2H]B[C6F4C(C6F5)2F]4.
Su p p or tin g In for m a tion Ava ila ble: Complete number-
ing scheme for the ORTEP including the N,N′-dimethyl-
anilinium cation. Tables of crystallographic data including
atomic coordinates, thermal parameters, and bond distances
and angles. This material is also available free of charge via
the Internet at http://pubs.acs.org.
P r oced u r e for Ma ss Sp ectr oscop y. The mass spectrum
was recorded using a PHI-Evans triple sector electrostatic
analyzer time-of-flight mass spectrometer equipped with a
pulsed liquid metal ion source (115In) for time-of-flight second-
(16) Sheldrick, G. M. SHELXTL, An Intergrated System for Solving,
Refining and Displaying Crystal Structures form Diffraction Data;
University of Gro¨ttingen: Federal Republic of Germany, 1981.
OM001080I