Preparation and structure of phosphonium ions with intramolecular P ← N coordination; Novel diphosphonium salts and ionomer containing backbone hypervalent phosphorus

Article abstract of DOI:10.1002/(SICI)1099-0682(200004)2000:4<647::AID-EJIC647>3.0.CO;2-N

Starting from R'R₂P (R' = 8-dimethylamino-1-naphthyl) containing a donor dimethylamino group, the new phosphonium salts [R'R₂P(CH₂Ph)]⁺Br^- [R = Me (9) or Ph (10)] and [R'R₂P(p-CH₂C₆H₄CH₂)PR₂R']²⁺[2Br]^2- [R = Ph (12)] have been prepared. An interaction between the N and P atoms is evident from the X-ray crystal structure of 10 the N-P distance being less than the sum of the van der Waals radii of the 2 atoms. The geometry of 10 is that of a monocapped tetrahedron whereas the X-ray crystal structure determination shows essentially regular tetrahedral geometry for the analogous compound without the donor amino group, [(1-Np)Ph₂P(CH₂Ph)]⁺Br^- (11). Treatment of 1,5-bis(dimethylamino)-2,6-dilithionaphthalene with chlorodiphenylphosphane gave 1,5-bis(dimethylamino)-2,6- bis(diphenylphosphanyl)-naphthalene (8) which in the presence of methyl iodide afforded the diphosphonium salt [1,5-bis(dimethylamino)-2,6- bis(diphenylmethylphosphonium)naphthalene]²⁺[2I]^2- (13). Similarly, treatment of 8 with 1 equivalent of benzyl bromide gave the monophosphonium salt [1,5-bis(dimethylamino)-2-diphenylbenzylphosphonium-6- diphenylphosphanyl-naphthalene]⁺[Br]^- (14) whereas in the presence of 2 equivalents of the same reagent [1,5-bis(dimethylamino)-2,6- bis(diphenylbenzylphosphonium)naphthalene]²⁺[2 Br]^2- (15) was obtained. The ionomer poly([(1,5-bis{dimethylamino}2,6- bis{diphenylphosphonium}naphthalene)-(P,P-p-xylylene)]²⁺[2 Br]^2-) (16), soluble in liquid SO₂, was prepared by treatment of 8 with α,α'-dibromo-p- xylene.

Full text of DOI:10.1002/(SICI)1099-0682(200004)2000:4<647::AID-EJIC647>3.0.CO;2-N

FULL PAPER
Preparation And Structure Of Phosphonium Ions With Intramolecular P ǟ N
Coordination; Novel Diphosphonium Salts And Ionomer Containing Backbone
Hypervalent Phosphorus
[a]
[a]
[a]
[a]
´
Francis H. Carre, Claude Chuit, Robert J. P. Corriu,* William E. Douglas,
[a]
[a]
´
Daniel M. H. Guy, and Catherine Reye
Keywords: Hypercoordinated phosphorus / Hypervalent phosphorus / Phosphorus / Diphosphonium compounds /
Ionomers
Starting from R’R2P (R’ = 8-dimethylamino-1-naphthyl) con-
taining a donor dimethylamino group, the new phosphonium
naphthalene (8) which in the presence of methyl iodide af-
forded the diphosphonium salt [1,5-bis(dimethylamino)-2,6-
salts [R’R2P(CH2Ph)]+Br– [R = Me (9) or Ph (10)] and [R’R2P( - bis(diphenylmethylphosphonium)naphthalene]2+[2I]2– (13).
CH2C6H4CH2)PR2R’]2+[2Br]2– [R = Ph (12)] have been pre-
pared. An interaction between the N and P atoms is evident
from the X-ray crystal structure of 10 the N–P distance being
less than the sum of the van der Waals radii of the 2 atoms.
The geometry of 10 is that of a monocapped tetrahedron
Similarly, treatment of 8 with 1 equivalent of benzyl bromide
gave the monophosphonium salt [1,5-bis(dimethylamino)-2-
diphenylbenzylphosphonium-6-diphenylphosphanyl-naph-
thalene]+[Br]– (14) whereas in the presence of 2 equivalents
of
the
same
reagent
[1,5-bis(dimethylamino)-2,6-
whereas the X-ray crystal structure determination shows es- bis(diphenylbenzylphosphonium)naphthalene]2+[2 Br]2– (15)
sentially regular tetrahedral geometry for the analogous was obtained. The ionomer poly([(1,5-bis{dimethylamino}-
compound without the donor amino group, [(1- 2,6-bis{diphenylphosphonium}naphthalene)-(P,P- -xyly-
Np)Ph2P(CH2Ph)]+Br– (11). Treatment of 1,5-bis(dimethylam- lene)]2+[2 Br]2–) (16), soluble in liquid SO2, was prepared by
ino)-2,6-dilithionaphthalene with chlorodiphenylphosphane treatment of 8 with α,α’-dibromo- -xylene.
gave 1,5-bis(dimethylamino)-2,6-bis(diphenylphosphanyl)-
Introduction
Extension of coordination has been widely investigated
for phosphoranes[1,2] and silicon compounds[3] but very
rarely in the case of phosphanes and phosphonium ions.[4]
It has been argued that there is no need to invoke d-orbital
participation in the bonding in such hypervalent phos-
phorus compounds.[5] We have described the preparation,
structures and some properties of various phosphanes (and
also some phosphonium salts) showing extension of coor-
dination by PǟN interactions,[6–8] incorporating in particu-
lar the 8-dimethylamino-1-naphthyl ligand first used many
years ago for the stabilization of hypercoordinated species[9]
and widely applied in silicon chemistry.[3] Here, some new
types of such phosphonium salts are reported including
Scheme 1. Preparation of 11
those containing two phosphorus atoms, prepared from the
4,8-bis(dimethylamino)-1,5-naphthylidene
ligand,[10]
in
which there are two PǟN interactions. The crystal structure
of one of the phosphonium salts is compared to that of the
corresponding salt without an amine group. We also describe
the preparation from this same ligand of a novel ionomer
containing hypervalent phosphorus in the backbone.
(Scheme 1). The presence of one molecule of diethyl ether
for each molecule of lithium reagent was shown by the pro-
ton NMR spectrum of the hydrolysis product. Naphthyldi-
phenylphosphane (2) was prepared by treatment of 1 with
chlorodiphenylphosphane (Scheme 1).
The hypercoordinate phosphanes were obtained starting
from the 8-(dimethylamino)-1-lithionaphthalene (3), the lat-
ter being prepared quantitatively by treatment of 1-di-
methylaminonaphthalene with n-butyllithium (Scheme 2).[9]
The preparation and the properties of phosphane 4 pre-
pared by treatment of 3 with chlorodiphenylphosphane
(Scheme 2) have been previously described;[8,12] a dynamic
proton NMR investigation and the X-ray crystal structure
determination showed that the geometry of this phosphane
Results and Discussion
Preparation of Starting Phosphanes
Naphthyllithium (1) was prepared by treatment of bro-
monaphthalene in diethyl ether with n-butyllithium[11]
[a]
´
CNRS UMR 5637, Universite Montpellier II,
Place E. Bataillon, 34095 Montpellier Cedex 5, France
E-mail: corriu@crit.univ-montp2.fr
Eur. J. Inorg. Chem. 2000, 647Ϫ653
WILEY-VCH Verlag GmbH, D-69451 Weinheim, 2000
1434Ϫ1948/00/0404Ϫ0647 $ 17.50ϩ.50/0
647

´
´
F. H. Carre, C. Chuit, R. J. P. Corriu, W. E. Douglas, D. M. H. Guy, C. Reye
FULL PAPER
Scheme 2. Preparation of hypervalent phosphorus compounds containing the 8-dimethylamino-1-naphthyl ligand
is not symmetric and that the distance between the nitrogen corresponding phosphane 4 with a monocapped tetrahedral
and the phosphorus atoms (2.7 A) is smaller than the sum arrangement of the ligands around each phosphorus.[8]
˚
of the van der Waals radii of the two atoms (3.4 A[13]).[8]
˚
The geometry of 4 can be described as a monocapped tetra-
hedron in which the P atom is pseudo-[4ϩ1]-coordinate
(taking into account the electron lone pair).[8]
Preparation of Phosphonium Salts
The very air sensitive hypercoordinate phosphonium salt
The intermediate dichlorophosphane derivative 5 was ob- 9 with methyl groups at P was prepared by treatment of 6
tained by addition of the lithium reagent 3 to a large excess with benzyl bromide (Scheme 2). The analogous stable salt
of trichlorophosphane (Scheme 2) at –80 °C. Treatment of 10 with phenyl groups at P was obtained by reaction of
5 with methyllithium gave the dimethylphosphane derivat- 4 with benzyl bromide. The X-ray crystal structure of 10
ive 6 (Scheme 2). The latter, like 4, shows a singlet for the (Figure 1) shows a monocapped tetrahedral geometry in
amine methyl protons in the proton NMR spectrum at which the P atom is [4ϩ1]-coordinate; selected bond lengths
room temperature. However, whereas for 4 this signal is and angles are to be found in Table 1 and details of the
split into two at –95 °C, in the case of 6 at –110 °C crystal structure determination in Table 2. The distance be-
˚
(250 MHz) it is merely broadened the permutational iso- tween the nitrogen and the phosphorus atoms (2.83 A) is
merization being of lower energy due to the difference in less than the sum of the van der Waals radii of the 2 atoms
bulk of the phenyl and methyl groups.
(3.4 A[13]),[8] thus showing that they interact. Indeed, this
˚
˚
Treatment of 1,5-bis(dimethylamino)naphthalene with distance is comparable to the N–N distance (2.79 A) in 1,8-
two equivalents of n-butyllithium affords the dilithio re- bis(dimethylamino)naphthalene[15] despite phosphorus be-
agent 7 (Scheme 3), as we have previously described.[10] ing much larger than nitrogen. Moreover, it should be noted
Subsequent treatment of 7 with chlorodiphenylphosphane that the naphthalene ring in 10 is distorted out of the plane
gives the diphosphane 8 containing two hypercoordinate by only ca. 17° (dihedral angle between the C9–C1–C2 and
phosphorus atoms (Scheme 3). A dynamic proton NMR C7–C8–C9 planes) whereas for 1,8-bis(dimethylamino)n-
study of this compound showed that at –95 °C the singlet aphthalene[15] the corresponding angle can be evaluated at
corresponding to the amine protons is split into two signals. 28°.
By use of the Eyring equation the energy of the permuta-
For comparison, the analogous phosphonium salt with-
tional isomerisation was calculated[14] to be ∆G‡ ϭ 36.8 kJ out the donor nitrogen, [(1-Np)Ph2P(CH2Ph)]ϩBr– (11),
mol–1, a value similar to that previously found for 4.[8] We was synthesized by treatment of 2 with benzyl bromide in
have not been able to determine the X-ray crystal structure refluxing toluene (Scheme 1). The X-ray crystal structure
of 8 but the geometry is most probably similar to that of the analysis of 11 (Figure 2) shows a tetrahedral geometry in
648
Eur. J. Inorg. Chem. 2000, 647Ϫ653

Phosphonium Ions With Intramolecular PN Coordination
FULL PAPER
Scheme 3. Preparation of hypervalent phosphorus compounds containing the 4,8-bis(dimethylamino)-1,5-naphthylidene ligand
˚
Table 1. Selected interatomic distances (A) and bond angles (°) for
10 and 11
10
11
P–C(1)
1.820(12)
1.787(11)
1.796(11)
1.844(11)
2.826(10)
175.7(4)
72.3(4)
1.790(5)
1.800(5)
1.815(5)
1.813(5)
P–C(11)
P–C(21)
P–C(30)
P
N
N
N
N
N
P–C(30)
P–C(1)
P–C(11)
P–C(21)
79.1(4)
75.8(4)
C(1)–P–C(30)
C(11)–P–C(30)
C(21)–P–C(30)
C(1)–P–C(11)
C(11)–P–C(21)
C(21)–P–C(1)
109.5(5)
103.6(5)
99.9(5)
110.6(5)
116.4(5)
115.3(5)
108.2(2)
109.1(2)
108.9(2)
110.4(2)
111.3(2)
109.0(2)
1
Figure 1. Molecular structure of 10; hydrogen atoms have been
omitted for clarity
The H NMR resonances for the methylene protons in
the hypercoordinate salts 9 (δH ϭ 4.4) and 10 (δH ϭ 4.7)
occur at higher field than in the tetracoordinate salt 11
which the P atom is 4-coordinate; selected bond lengths and (δH ϭ 5.35). This can be explained by the electron-donating
angles are to be found in Table 1 and details of the crystal effect of the dimethylamino group coordinated to the phos-
structure determination in Table 2. Comparison of the phorus atom. However, the 31P NMR chemical shift re-
angles in 10 and 11 (Table 1) shows that the nitrogen in 10 mains essentially unchanged with increase in the coordina-
is opposite to the benzyl group [C(30)] and has little effect tion number from four (11) to five (9 or 10) as has previ-
on angles C(1)–P–C(30) and C(1)–P–C(11) which remain ously been observed for hypercoordinated silicon com-
essentially tetrahedral. However, the presence of the amine pounds containing the 8-dimethylamino-1-naphthyl
group results in a reduction of C(21)–P–C(30) by ca. 9° and ligand.[16]
C(11)–P–C(30) by ca. 6°, and an enlargement of C(11)–P–
C(21) and C(21)–P–C(1) by 5–6°.
The analogous compound 12 containing two positively-
charged phosphorus atoms was prepared by treating two
Eur. J. Inorg. Chem. 2000, 647Ϫ653
649

´
´
F. H. Carre, C. Chuit, R. J. P. Corriu, W. E. Douglas, D. M. H. Guy, C. Reye
FULL PAPER
Table 2. Summary of crystal data, intensity measurements and refinement for 10 and 11
10
11
Formula
C31H29BrNP
triclinic
P–1
C29H24BrP
monoclinic
P21/c
10.123(2)
20.683(4)
11.796(3)
Cryst. system
Space group
˚
a (A)
9.351(3)
9.875(3)
14.664(4)
80.58(2)
74.27(3)
89.66(3)
1284.8(7)
526.46
˚
b (A)
˚
c (A)
α
β
γ
110.29(2)
3
˚
Vol. (A )
2316.5(9)
483.4
Mol. wt.
Z
2
4
dcalcd. (gcm–3)
dmeasd. (gcm–3)
Cryst. size (mm)
Cryst. colour
1.361
1.386
1.32(3)
1.37(2)
0.42 ϫ 0.40 ϫ 0.18
colourless
ethanol
329.5–331.2
ω/ϕ
0.45 ϫ 0.25 ϫ 0.09
colourless
CH2Cl2/heptane, 2:3
281.3–282.5
ω/ϕ
Recryst. solv.
m.p. (°C)
Method of data collectn.
Radiation (graphite-monochromated)
µ (cm–1)
Mo-Kα
16.6
Mo-Kα
18.2
2ϕ limits (°)
4–50
4–50
No of unique reflectns.
No of obsd reflectns.
Final no of variables.
R
3275
3338
1548
2106
161
180
0.0690
0.0396
0.0409
0.41
Rw
0.0705
Residual electron density
0.98
spectra showing the disappearance of the signal corres-
ponding to the starting phosphane (δP ϭ 1.9) and the ap-
pearance of the signal corresponding to the phosphonium
salt at δ ഠ 23. Salt 13 was prepared by treatment of phos-
phane 8 with a large excess of methyl iodide in toluene un-
der reflux, the reaction being complete after 4.5 h
(Scheme 3).
The compound 14 containing both phosphanyl and pho-
sphonium centres was obtained by treatment of 8 with one
equivalent of benzyl bromide the reaction being complete
after 60 hours under reflux in toluene (Scheme 3). The 31P
NMR spectrum shows a signal at δ 22 characteristic of the
phosphonium ion and another at δ ϭ 5 corresponding to
the phosphanyl atom, the latter being downfield of that for
the starting material 8 (δP ϭ 1.9). The proton resonances
for the dimethylamino group peri to the phosphonium
centre (δH ϭ 1.7) are shifted upfield compared to those for
8 (δH ϭ 2.3) whereas the proton resonances for the di-
methylamino group para to the phosphonium centre are
shifted downfield (δH ϭ 2.5).
Figure 2. Molecular structure of 11; hydrogen atoms have been
omitted for clarity
The analogous salt 15 containing two phosphonium
centres was prepared by treatment of 8 with two equivalents
of benzyl bromide the reaction being complete in this case
after 120 hours under reflux in toluene (Scheme 3). As ex-
pected only one 31P NMR signal is observed (δP ϭ 24.8)
characteristic of the phosphonium ion. The proton NMR
spectrum shows all the amine protons to be equivalent
(δH ϭ 2.08) this signal being upfield of that for 8 (δH ϭ 2.3).
equivalents of 4 with one equivalent of α,α’-dibromo-p-xy-
lene (Scheme 2). As expected the chemical shifts of the pro-
ton and 31P NMR resonances for 12 are very similar to
those for 10, the 31P NMR resonances for these compounds
containing phenyl groups occurring at higher field than that
for 9 containing methyl groups.
Phosphonium salts containing two hypercoordinate
The ionomer 16 was prepared by heating 8 with one
phosphorus atoms were obtained from the diphosphane 8 equivalent of α,α’-dibromo-p-xylene in toluene under reflux
(Scheme 3). The reactions were followed by 31P NMR, the for 10 d (Scheme 3), the product being insoluble except in
650
Eur. J. Inorg. Chem. 2000, 647Ϫ653

Phosphonium Ions With Intramolecular PN Coordination
FULL PAPER
liquid SO2. The solid state 31P NMR spectrum shows a sig-
nal at δ ϭ 16. The conductivity of a compacted disc of the
powdered ionomer was found to be 10–5 S cm–1 (4-point
method), and that of a SO2 solution at –30 °C was 53 S
cm–1.
m, 1329 w, 1094 w, 1027 w. – C22H17P (312.34): calcd. C 84.60, H
5.48, P 9.91; found C 85.01, H 5.48, P 9.78.
Preparation of 3: n-Butyllithium in hexane (40 mL, 110 mmol) was
added drop by drop to a solution of 1-(dimethylamino)naphthalene
(16.54 g, 96.7 mmol) in 250 mL of diethyl ether at room temp. After
the mixture had been stirred for 3 d the resulting yellow suspension
was filtered and the precipitate was washed thrice with diethyl ether
before being dried under vacuum to afford 16.8 g of a yellow pyro-
phoric fine powder (yield 98%).
In conclusion, we have shown that an intramolecular
donor-acceptor interaction exists in the phosphonium ion
10 and therefore most probably also in the other new phos-
phonium ions of this type reported here (9, 12, 13–15 and
the ionomer 16). This confirms that the phosphonium ion
is able to undergo an extension of coordination. In particu-
lar, it should be noted that, as has been previously observed
for the analogous silicon compounds,[16] incorporation of
the 8-dimethylamino-1-naphthyl ligand to give pentacoord-
inate phosphane species does not give rise to any substantial
change in NMR chemical shift. This independence of NMR
chemical shift on coordination number is due to the specific
geometry of the ligand and in no way throws doubt[17] on
the existence of an NǟP (or NǟSi) coordinative interac-
tion. On the contrary, a completely coherent picture is
found for the structures and chemical behaviour of the to-
tality of penta- and hexacoordinate derivatives formed by
intramolecular coordination of either Si or P.
Preparation of 5: A suspension of 3 (5.67 g, 32.03 mmol) in 150 mL
of diethyl ether was added drop by drop to a solution of trichloro-
phosphane (12 mL, 137 mmol) in 150 mL of diethyl ether at –80
°C. The mixture was stirred at room temp. overnight. The resulting
yellow suspension was filtered and the filtrate was concentrated to
give 5.43 g of a yellow solid (yield 62%). – 1H NMR (CDCl3): δH ϭ
2.87 [s, 6 H, N(CH3)2], 7.5–8.9 (m, 6 H, aromatic protons). – 13C-
{1H} NMR (CDCl3): δC ϭ 47.6 (CH3), 112–148 (aromatic car-
bons). – 31P-{1H} NMR (CDCl3): δP ϭ 130.85 (s).
Preparation of 6: A 1.25  solution of methyllithium (28.2 mL,
35.22 mmol) in diethyl ether was added to a suspension of 5 (4.79 g,
17.61 mmol) in 100 mL of diethyl ether. The mixture was stirred at
room temperature overnight and then heated under reflux for 3 h.
The suspension was hydrolysed by addition of degassed 10%
NaOH solution (40 mL). The aqueous layer was extracted with di-
ethyl ether. The combined organic phases were washed with de-
gassed water and dried with MgSO4 before removal of the solvent
to give a yellow liquid. Vacuum distillation gave 1.63 g of the de-
sired product (40% yield), b.p. 118–120 °C/0.4 Torr. – 1H NMR
Experimental Section
2
All reactions were performed using standard Schlenk-tube tech-
niques under an atmosphere of dry argon. Solvents were distilled
from appropriate drying agents and degassed before use. 1H and
13C NMR spectra were obtained using a Bruker DPX-200 spectro-
meter at 200 MHz and 50.288 MHz, respectively, and 31P NMR
spectra on a Bruker 250 AC spectrometer at 101.202 MHz. 1H and
13C NMR chemical shifts are reported relative to Me4Si, and 31P
chemical shifts relative to H3PO4. Infrared spectra were obtained
in the region 500–4000 cm–1 using a Perkin–Elmer 1600 FT spec-
trophotometer. Elemental analyses were carried out by the Service
Central de Microanalyse du CNRS. Phosphane 4 was prepared
from 3 as previously described.[8]
(CDCl3): δH ϭ 1.35 [d, J1H,31P ϭ 5.7 Hz, 6 H, P(CH3)2], 2.75 [s, 6
H, N(CH3)2], 7.3–7.9 (m, 6 H, aromatic protons). – 31P-{1H} NMR
(CDCl3): δP ϭ –37.8 (s). – IR (CCl4): ν˜ (cm–1) ϭ 3054 m, 2945 s,
2902 s, 2864 s, 2828 vs, 2786 s, 1929 w, 1710 w, 1563 vs, 1500 w,
1477 m, 1453 vs, 1366 vs, 1330 s, 1289 m, 1204 m, 1183 s, 1143 s,
1081 s, 1048 m, 1030 m.
Preparation of 7: n-Butyllithium in hexane (110 mL, 310 mmol) was
added drop by drop to a solution of 1,5-bis(dimethylamino)naph-
thalene (30.04 g, 140 mmol) in 500 mL of diethyl ether at room
temp.. After the mixture had been stirred for 10 d the resulting
yellow suspension was filtered and the precipitate was washed
thrice with diethyl ether before being dried under vacuum to afford
30.97 g of a white pyrophoric fine powder (yield 98%).
Preparation of 1: Diethyl ether (130 mL) was added at 0 °C to 1.9
 n-butyllithium solution in hexane (85 mL, 160 mmol) and the
resulting solution was cooled to –20 °C. 1-Bromonaphthalene
(20 mL, 140 mmol) was added drop by drop and the mixture was
stirred at 0 °C for 1 h and then filtered. The precipitate was washed
with pentane and dried under vacuum affording 24.65 g of a white
pyrophoric solid (C10H7Li Et2O) isolated in 85% yield.
Preparation of 8: Chlorodiphenylphosphane (10.83 mL, 60 mmol)
was added drop by drop to a suspension of 7 (8.52 g, 38 mmol) in
100 mL of diethyl ether at –80 °C. The mixture was then allowed
to warm to room temp. and was stirred overnight. The resulting
white suspension was heated under reflux for 9 h, and it was then
hydrolysed with 10% NaOH solution (100 mL). The precipitate was
washed successively with water, acetone and diethyl ether before
being dried under vacuum. The crude product was recrystallized
Preparation of 2: Chlorodiphenylphosphane (18 mL, 100 mmol)
was added drop by drop to a suspension of 1 (16 g, 76.92 mmol)
in diethyl ether (100 mL) at –50 °C. The mixture was then allowed from benzene to give 9.6 g of the desired product, m.p. 259.4–263.7
1
to warm to room temp. and was stirred for 16 h. The resulting
white suspension was heated under reflux for 5 h, and was then
°C (yield 55%). – H NMR (CDCl3): δH ϭ 2.3 [s, 12 H, N(CH3)2],
6.7–7.4 (m, 24 H, aromatic protons). – 13C-{1H} NMR (CDCl3):
hydrolysed with 10% NaOH solution (50 mL). The precipitate was δC ϭ 46.18 [N(CH3)2], 118–152 (aromatic carbon atoms). – 31P-
washed successively with water, acetone and diethyl ether before
being dried under vacuum. The crude product was recrystallized
from ethanol to give 13.25 g of the desired product, m.p. 122.3–
124.0 °C (yield 55%). – 1H NMR (CDCl3): δH ϭ 7–8.6 (m, aro-
{1H} NMR (CDCl3): δP ϭ 1.9 (s). – IR (Nujol): ν˜ (cm–1) ϭ 3059
m, 2853 vs, 2822 s, 2776 m, 1954 w, 1882 w, 1823 w, 1773 w, 1677
w, 1653 w, 1578 m, 1506 m, 1451 s, 1401 w, 1368 s, 1311 m, 1275
w, 1202 m, 1181 s, 1152 m, 1109 m, 1087 m, 1068 w, 1042 s, 976
matic protons). – 13C-{1H} NMR (CDCl3): δC ϭ 126–137 (aro- vs, 836 m, 826 m, 748 s, 738 vs, 717 m, 697 vs, 668 w, 650 m, 613
matic carbons). – 31P-{1H} NMR (CDCl3): δP ϭ –13.6 (s). – IR s. – C38H36N2P2 (582.66): C 78.32, H 6.23, N 4.81; found C 78.28,
(CCl4): ν˜ (cm–1) ϭ 3056 s, 1588 w, 1504 m, 1482 m, 1434 vs, 1386
Eur. J. Inorg. Chem. 2000, 647Ϫ653
H 6.01, N 4.92.
651

´
´
F. H. Carre, C. Chuit, R. J. P. Corriu, W. E. Douglas, D. M. H. Guy, C. Reye
FULL PAPER
Preparation of 9: A mixture of 6 (0.33 g, 1.43 mmol) and benzyl
bromide (0.17 mL, 1.43 mmol) was heated under reflux in toluene
(50 mL) for 3 h. The solvent was removed under vacuum to give
0.53 g of a very air-sensitive white powder (yield 93%). – 1H NMR
s, 1211 w, 1155 m, 1121 s, 1101 m, 1038 w, 1012 w, 996 w, 972 m,
914 m, 895 m, 830 w, 785 w, 774 w, 750 s, 715 s, 693 s.
Preparation of 14:
A mixture of benzyl bromide (0.61 mL,
5.15 mmol) and 8 (3 g, 5.15 mmol) was heated under reflux in tolu-
ene (50 mL) for 60 h. The solvent was removed under vacuum to
give a yellow solid, m.p. 275.8–276.5 °C (yield 83%). – 1H NMR
(CDCl3): δH ϭ 1.7 [s, 6 H, N(CH3)2 peri to Pϩ], 2.5 [s, 6 H,
2
(CDCl3): δH ϭ 2.45 [d, J1H,31P ϭ 10 Hz, 6 H, P(CH3)2], 2.75 [s, 6
2
31
H, N(CH3)2], 4.4 (d, J1
ϭ 15 Hz, 2 H, CH2), 6.8–8.2 (m, 11
H
P
H, aromatic protons). – 31P-{1H} NMR (CDCl3): δP ϭ 24.26 (s).
2
Preparation of 10: A mixture of 4 (2 g, 5.63 mmol) and benzyl
bromide (0.67 mL, 5.63 mmol) was heated under reflux in toluene
(100 mL) for 9 d. The solvent was then removed under vacuum to
give a white solid. The crude product was recrystallized from a
mixture of dichloromethane and heptane to give 2.84 g of the de-
N(CH3)2 para to Pϩ], 4.7 (d, J1H,31P ϭ 14 Hz, CH2), 6–7.8 (m, 29
H, aromatic protons). – 13C-{1H} NMR (CDCl3): δC ϭ 38.6 (d,
1J13C,31P ϭ 47.23 Hz, CH2), 45.72 [N(CH3)2], 46.16 [N(CH3)2], 119–
150 (aromatic carbon atoms). – 31P-{1H} NMR (CDCl3): δP ϭ 4.3
(P), 21.91 (Pϩ). – IR (Nujol): ν˜ (cm–1) ϭ 3045 w, 1584 w, 1558 w,
1498 m, 1376 vs, 1322 m, 1303 m, 1261 w, 1185 m, 1151 m, 1116
sired product, m.p. 281.3–282.5 °C (yield 96%). – 1H NMR
2
(CDCl3): δH ϭ 1.5 [s, 6 H, N(CH3)2], 4.7 (d, J1H,31P ϭ 14 Hz, 2 s, 1073 m, 1046 w, 1033 m, 998 m, 971 m, 904 m, 860 m, 837 m,
H, CH2), 6.3–9 (m, 21 H, aromatic protons). – 13C-{1H} NMR 753 s, 723 m, 697 s.
1
(CDCl3): δC ϭ 36.14 (d, J31P,13C ϭ 48.36 Hz, CH2), 46.44 (CH3),
Preparation of 15:
A mixture of benzyl bromide (1.22 mL,
111–151 (aromatic carbons). – 31P-{1H} NMR (CDCl3): δP ϭ 22.12
(s). – IR (Nujol): ν˜ (cm–1) ϭ 3052 w, 2796 w, 1715w, 1694 w, 1570
w, 1497 m, 1438 s, 1412 w, 1376 m, 1338 m, 1286 w, 1209 w, 1195
w, 1152 m, 1114 s, 1105 s, 1081 m, 1036 m, 1023 m, 995 w, 958 w,
929 w, 879 m, 839 s, 831 s, 802 w, 776 vs, 757 s, 727 m, 699 vs, 660.
10.30 mmol) and 8 (3 g, 5.15 mmol) was heated under reflux in
toluene (50 mL) for 120 h. The solvent was removed under vacuum
to give a yellow powder. The crude product was recrystallized from
a mixture of ethanol and benzene to give 4.52 g of the desired prod-
1
uct, m.p. 294.0–294.6 °C (yield 95%). – H NMR (CDCl3): δH
ϭ
2
Preparation of 11: A mixture of naphthyldiphenylphosphane (2)
(2 g, 6.41 mmol) and benzyl bromide (0.76 g, 6.41 mmol) was
2.08 [s, 12 H, N(CH3)2], 4.87 (d, J1H,31P ϭ 16 Hz, 4 H, CH2), 6.5–
9 (m, 34 H, aromatic protons). – 13C-{1H} NMR (CDCl3): δC
ϭ
1
heated under reflux in toluene (100 mL) for 6 d. The solvent was 38.8 (d, J13C,31P ϭ 47.66 Hz, CH2), 46.06 (CH3), 119–150 (aro-
removed under vacuum to give a white powder. The crude product
matic carbons). – 31P-{1H} NMR (CDCl3): δP ϭ 24.78 (s). – IR
(Nujol): ν˜ (cm–1) ϭ 2786 w, 1574 w, 1498 s, 1439 vs, 1376 s, 1315
m, 1260 w, 1175 w, 1112 m, 1074 w, 1037 m, 1010 w, 973 w, 904 w,
was recrystallized from ethanol to give 1.81 g of the desired prod-
1
uct, m.p. 329.5–331.2 °C (yield 58%). – H NMR (CDCl3): δH
ϭ
2
5.35 (d, J1H,31P ϭ 15 Hz, 2 H, CH2), 6.8–8.6 (m, 22 H, aromatic 851 m, 838 m, 786 w, 761 m, 750 s, 726 m, 696 s.
1
protons). – 13C-{1H} NMR (CDCl3): δC ϭ 30.53 (d, J13C,31P
ϭ
Preparation of 16: A mixture of α,α’-dibromo-p-xylene (0.73 g,
2.78 mmol) and 8 (1.62 g, 2.78 mmol) was heated under reflux in
toluene (50 mL) for 10 d. The solvent was removed under vacuum
to give an orange powder (d 300 °C) which is soluble in liquid SO2.
Solid-state 31P-NMR HPDEC MAS: δP ϭ 16. – IR (Nujol):
ν˜ (cm–1) ϭ 2722 w, 1614 w, 1568 m, 1498 s, 1438 vs, 1377 vs, 1315
m, 1261 m, 1211 m, 1157 m, 1110 s, 1033 m, 998 m, 968 m, 899 w,
837 s, 749 m, 720 w, 694 s, 634 w.
42.78 Hz, CH2), 112–138 (aromatic carbon atoms). – 31P-{1H}
NMR (CDCl3): δP ϭ 22.45 (s). – IR (nujol): ν˜ (cm–1) ϭ 2783 m,
2362 w, 1602 w, 1586 w, 1502 m, 1496 m, 1440 vs, 1377 s, 1338 m,
1318 w, 1262 w, 1214 w, 1166 m, 1110 s, 1074 w, 1033 w, 997 w,
986 w, 921 w, 877 w, 832 m, 800 m, 777 s, 751 s, 717 m, 698 s, 690
s, 664 w, 586 s. – C29H24BrP (483.39): C 72.06, H 5.00; found C
72.06, H 5.09.
Preparation of 12: A mixture of α,α’-dibromo-p-xylene (0.74 g,
2.81 mmol) and 4 (2 g, 5.63 mmol) was heated under reflux in tolu-
ene (100 mL) for 7 d. The solvent was removed under vacuum to
give a white powder. The crude product was recrystallized from a
mixture of dichloromethane and pentane to give 1.6 g of the desired
product, m.p. 309.9–311.4 °C (yield 58%). – 1H NMR (CDCl3):
δH ϭ 1.5 [s, 12 H, N(CH3)2], 4.55 (d, 2J1H,31P ϭ 16 Hz, 4 H, CH2),
7–9 (m, 36 H, aromatic protons). – 13C-{1H} NMR (CDCl3): δC ϭ
X-ray Structure Determinations of 10 and 11: The crystal of 10 used
was found to produce only moderate diffraction intensities. The
direct methods (SHELXS-86[18]) failed to give the solution of the
structure with space groups P–1. However, an attempt to solve the
structure with the non-centrosymmetric space group P1 gave the
positions of the bromine anion, the phosphorus atom and four car-
bon atoms from the naphthyl group. The space group P–1 was
again assumed to be the correct group and two subsequent Fourier
syntheses and a difference Fourier map gave the positions of the
remaining atoms. Owing to the small number of observed data,
only the bromine, phosphorus and nitrogen atoms were refined an-
isotropically. The calculated hydrogen atoms[19] were included in
the last stages of the refinement. Convergence occurred for the R
value of 0.0690 (Rw ϭ 0.0705). – In the case of 11 the systematic
absences revealed the space group P21/c. Direct methods
1
38.25 (d, J13C,31P ϭ 47.44 Hz, CH2), 46.4 (CH3), 110–150 (aro-
matic carbons). – 31P-{1H} NMR (CDCl3): δP ϭ 22.77 (s). – IR
(Nujol): ν˜ (cm–1) ϭ 3053 w, 2854 vs, 2808 w, 1622 w, 1566 w, 1497
w, 1437 s, 1375 s, 1336 m, 1288 w, 1212 w, 1168 m, 1151 w, 1110 s,
1100 m, 1080 w, 1034 w, 1024 w, 995 w, 954 w, 880 w, 826 m, 773
m, 756 s, 724 m, 697 m, 658 w.
Preparation of 13: A mixture of methyl iodide (1.74 g, 28.0 mmol)
and 8 (2 g, 3.44 mmol) was heated under reflux in toluene (20 mL) (SHELXS-86[18]) gave the positions of the bromine anion, the phos-
for 4.5 h. The solvent was removed under vacuum to give a white
powder. The crude product was recrystallized in a mixture of eth-
anol and benzene to give 2.48 g of the desired product, m.p. 323.7–
phorus atom and the phenyl and some of the naphthyl carbons.
Two Fourier maps revealed the remaining carbon atoms. The hy-
drogen atoms were positioned by calculation[19] and taken into ac-
count in the next refinements. After ten cycles of least-squares re-
324.9 °C (yield 83%). – 1H NMR (CDCl3): δH ϭ 2.1 [s, 12 H,
2
N(CH3)2], 3.1 (d, J1H,31P ϭ 13.4 Hz, 6 H, PCH3), 7.2–7.8 (m, 24 finement with anisotropic thermal parameters for all non-hydrogen
H, aromatic protons). – 13C-{1H} NMR (CDCl3): δC ϭ 11.84 (d,
1J13C,31P ϭ 65.17 Hz, PCH3), 46.67 [N(CH3)2], 111–157 (aromatic
atoms, the final R value was 0.0396 (Rw ϭ 0.0409). – The crystal
structure data (excluding structure factors) have been deposited
carbon atoms). – 31P-{1H} NMR (CDCl3): δP ϭ 23.76 (s). – IR with the Cambridge Crystallographic Data Centre as supplement-
(Nujol): ν˜ (cm–1) ϭ 1585 w, 1567 m, 1499 s, 1438 vs, 1376 vs, 1318 ary publication nos. CCDC-114826 (10) and -114825 (11). Copies
652
Eur. J. Inorg. Chem. 2000, 647Ϫ653

Phosphonium Ions With Intramolecular PN Coordination
FULL PAPER
C. Breliere, R. J. P. Corriu, G. Royo, M. Wong Chi Man, J.
Zwecker, C. R. Acad. Sci. Paris Serie II 1991, 313, 1527.
L. Brandsma, H. Verkruijsse, Preparative Polar Organometallic
Chemistry 1, Springer-Verlag, Berlin, Heidelberg, New York,
London, Paris, Tokyo, 1987.
G. P. Schiemenz, E. Papageorgiou, Phosphorus and Sulfur 1982,
13, 41.
A. Bondi, J. Phys. Chem. 1964, 68, 441.
[10]
[11]
`
of the data can be obtained free of charge on application to CCDC,
12 Union Road, Cambridge CB2 1EZ, G.B. [Fax: int. code ϩ 44-
1223/336-033; E-mail: deposit@ccdc.cam.ac.uk].
´
[12]
[1]
[13]
[14]
[15]
R. H. Holmes, Chem. Rev. 1996, 96, 927.
C. Y. Wong, D. K. Kennepohl, R. G. Cavell, Chem. Rev. 1996,
96, 1917.
[2]
H. Günther, NMR Spectroscopy, Wiley, Chichester, 1980.
H. Einspahr, J. B. Robert, R. E. Marsh, J. D. Roberts, Acta
Cryst. 1973, B29, 1611.
[3]
´
C. Chuit, R. J. P. Corriu, C. Reye, J. C. Young, Chem. Rev.
[16]
[17]
[18]
`
C. Breliere, R. J. P. Corriu, G. Royo, J. Zwecker, Organometal-
1993, 93, 1371.
[4]
[5]
[6]
lics 1989, 8, 1834.
´
C. Chuit, C. Reye, Eur. J. Inorg. Chem. 1998, 1847.
G. P. Schiemenz, B. Schiemenz, S. Petersen, C. Wolff, Chirality
1998, 10, 180.
G. M. Sheldrick, SHELXS-86, A Program for Crystal Structure
Solution, Institüt für Anorganische Chemie der Universität:
Göttingen, Germany, 1986.
D. G. Gilheany, Chem. Rev. 1994, 94, 1339.
C. Chuit, R. J. P. Corriu, P. Monforte, C. Reye, J. P. Declercq,
A. Dubourg, Angew. Chem. Int. Ed. Engl. 1993, 32, 1430.
M. Chauhan, C. Chuit, R. J. P. Corriu, C. Reye, J. P. Declercq,
A. Dubourg, J. Organomet. Chem. 1996, 510, 173.
C. Chuit, R. J. P. Corriu, P. Monforte, C. Reye, J. P. Declercq,
A. Dubourg, J. Organomet. Chem. 1996, 511, 171.
´
[7]
[8]
[9]
´
[19]
G. M. Sheldrick, SHELXS-76, A Program for Crystal Structure
Determination, University of Cambridge: Cambridge, Eng-
land, 1976.
´
J. T. B. H. Jastrzebski, C. T. Knaap, G. van Koten, J. Or-
ganomet. Chem. 1983, 255, 287.
Received September 27, 1999
[I99336]
Eur. J. Inorg. Chem. 2000, 647Ϫ653
653