Synthesis of ferrocenylphenyl derivatives including biphenylferrocenes, arylferrocenylphenyl ethers and arylferrocenylphenyl amines

Article abstract of DOI:10.1016/S0022-328X(01)01410-3

The preparation of a series of substituted biphenylferrocenes via a modified Suzuki reaction between 4-bromophenylferrocene and substituted acids is described. The X-ray crystal structure of 4′-formly-4-biphenylferrocene is reported and this compound is then incorporated into the first series of ferrocenomesogens containing the ferrocenylbiphenyl unit. The synthesis of a series of arylferrocenylphenyl ethers and arylferrocenylphenyl amines is also described.

Full text of DOI:10.1016/S0022-328X(01)01410-3

Journal of Organometallic Chemistry 645 (2002) 65–81
www.elsevier.com/locate/jorganchem
Synthesis of ferrocenylphenyl derivatives including
biphenylferrocenes, arylferrocenylphenyl ethers and
arylferrocenylphenyl amines
Christopher Imrie a,*, Pieter Engelbrecht a, Christa Loubser, Cedric W. McCleland a,
Vincent O. Nyamori a, Robert Bogardi b, Demetrius C. Levendis b,
Nomfuneko Tolom a, Jason van Rooyen a, Nadia Williams a
a Department of Chemistry, Uni6ersity of Port Elizabeth, P.O. Box 1600, Port Elizabeth 6000, South Africa
b Department of Chemistry, Centre for Molecular Design, Uni6ersity of the Witwatersrand, Johannesburg, South Africa
Received 18 June 2001; received in revised form 27 September 2001; accepted 8 October 2001
Abstract
The preparation of a series of substituted biphenylferrocenes via a modified Suzuki reaction between 4-bromophenylferrocene
and substituted phenylboronic acids is described. The X-ray crystal structure of 4%-formyl-4-biphenylferrocene is reported and this
compound is then incorporated into the first series of ferrocenomesogens containing the ferrocenylbiphenyl unit. The synthesis of
a series of arylferrocenylphenyl ethers and arylferrocenylphenyl amines is also described. © 2002 Elsevier Science B.V. All rights
reserved.
Keywords: Biphenylferrocenes; Arylferrocenylphenyl ethers; Arylferrocenylphenyl amines
tionalized phenyl or biphenyl compound. It was estab-
lished that a minimum of three aromatic rings in the
substituent core, Z, are necessary for stabilizing a ne-
matic liquid crystal phase, and that four rings substan-
tially enhance the nematic behavior. It was also
established that it is advantageous to insert at least one
phenyl ring between the ferrocenyl group and the linker
(the group which connects the rigid conjugated sections
of liquid crystals). With a view to extending the range
of monosubstituted ferrocenomesogens, it was decided
1. Introduction
Following the publication in 1993 by Loubser et al.
[1] of the first X-ray crystal structure of a monosubsti-
tuted ferrocenomesogen (ferrocenyl-containing liquid
crystal), in which it was shown that a bulky terminal
ferrocenyl group could be readily incorporated into the
supramolecular architecture, there has been a signifi-
cant interest in these compounds amongst chemists [2].
A question that has been at the forefront of our re-
search methodology from the start is: what are the
structural limits within which the liquid-crystalline state
can be generated and retained in these molecules? In
1997, we reported on the liquid crystal properties of a
series of compounds represented by the general struc-
ture shown in Fig. 1[3].
The compounds in this series were readily synthesized
by reacting a 4-substituted phenylferrocene (in these
examples 4-ferrocenylbenzoic acid, j=1) with a func-
Fig. 1. General structure representing the compounds prepared by
Loubser and Imrie.
* Corresponding author. Fax: +27-41-504-2573.
E-mail address: chacci@upe.ac.za (C. Imrie).
0022-328X/02/$ - see front matter © 2002 Elsevier Science B.V. All rights reserved.
PII: S0022-328X(01)01410-3

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C. Imrie et al. / Journal of Organometallic Chemistry 645 (2002) 65–81
Table 1
Yields of biphenylferrocenes from the reaction of 4-bromophenylferrocene with substituted phenylboronic acids
Entry
X
4-Bromophenylferrocene (mmol)
Time (days)
Yield (%) a
b
1
2
3
4
5
6
7
8
9
4-OCH3
4-CH3
1.5
1.5
1.5
1.5
3.0
3.0
3.0
3.0
3.0
1.5
1.5
14
14
14
14
21
32
1
14
14
14
14
93
88
65
79
50
13
10
89
14
70
38
b
b
4-OC8H17
4-Ph b
4-CHO c
4-CHO b
4-CHO b
4-F b
c
4-COCH3
10
11
4-CH2Ph c
b
3-NO2
a Yields are based on 4-bromophenylferrocene.
b Typical procedure: to 90% ethanol, which was degassed by purging with nitrogen for 48 h, deaerated by the freeze-thaw method (3 cycles) and
finally purged with nitrogen for another 24 h was added the subsitituted phenylboronic acid (two equivalents), 4-bromophenylferrocene (one
equivalent), barium hydroxide (1.4 equivalents) and palladium(II) acetate (0.3 equivalents) under nitrogen. The reaction mixture was then
vigorously shaken for 30 min prior to stirring under nitrogen.
c The same procedure as described for (b) with the exception that the reaction mixture was intermittently heated under reflux (7×7 h).
to synthesize molecules where j=2 (Fig. 1) and for this,
it was necessary to synthesize 4-substituted biphenylfer-
rocenes. It was also decided to introduce new linking
units into the general structure, namely the ether (YꢀO)
and the amine linkage (YꢀNH). For this, a synthesis of
arylferrocenylphenyl ethers and arylferrocenylphenyl
amines was required.
There are few references to ferrocenylbiphenyl com-
pounds in the literature. The crystal structures of 4-
biphenylylferrocene 1 [4] and 2-biphenylylferrocene 2
2. Results and discussion
[5] have been determined. The two compounds are also
mentioned in the context of several other papers in the
early literature of ferrocene chemistry concerned with
the arylation of ferrocene via the reaction of ferrocene
with diazonium ions [6].
2.1. Synthesis of substituted biphenylferrocenes
The optimum reaction conditions that were deter-
mined in earlier work by us for modified Suzuki cross-
coupling reactions of iodoferrocene with arylboronic
acids were employed for the reactions of 4-bro-
mophenylferrocene and phenylboronic acids. The reac-
tions were performed using palladium(II) acetate as
catalyst, barium hydroxide as base and 90% EtOH as
solvent. The reactions were carried out at either room
temperature (in the cases where the phenylboronic acid
contained an electron-donating group) or under reflux
(in the cases where the phenylboronic acid contained an
electron-withdrawing group). Thorough degassing of
the solvent is crucial and was carried out by nitrogen
purging and the freeze-thaw technique. The isolated
yields of the products ranged from good-to-excellent in
most cases (Table 1). A summary of the reactions is
We have recently reported the use of a modified
Suzuki cross-coupling procedure for the synthesis of
4-substituted phenylferrocenes [7]. Iodoferrocene was
reacted with a series of 4-substituted phenylboronic
acids in the presence of a base and catalyst to provide
a range of 4-substituted phenylferrocenes. One of the
products from the initial work was 4-bromophenylfer-
rocene 3. This article discusses the use of 3 in the
efficient synthesis of 4-substituted biphenylferrocenes
by a modified Suzuki cross-coupling reaction. It also
discusses the first synthesis of arylferrocenylphenyl
ethers and arylferrocenylphenyl amines by the reaction
of phenylboronic acids with 4-ferrocenylphenol and
4-ferrocenylaniline, respectively.

C. Imrie et al. / Journal of Organometallic Chemistry 645 (2002) 65–81
67
shown in Fig. 2. In comparison to the reactions using
2.2. Synthesis of arylferrocenylphenyl ethers
iodoferrocene, it was found that the current reactions
gave significantly higher overall yields and were gener-
ally more efficient. The starting material was recovered
in only trace quantities in most of the reactions as
compared to reactions with iodoferrocene in which
considerable amounts of starting material was recov-
ered. Of particular interest for the synthesis of liquid
crystals were 4-substituted biphenylferrocenes in which
the substituent could be further derivatized. For exam-
ple, 4%-formyl-4-biphenylferrocene 4 was prepared in
one step. In the initial attempts to synthesize 4 (entries
6 and 7, in Table 1), the reactions were performed at
room temperature and the overall yields of product
were very low. For entry 5, the reaction was heated
intermittently and this resulted in a significant improve-
ment in the yield of 4. 4%-Hydroxy-4-biphenylferrocene
5 was synthesized in either a one or two step reaction
from 4-bromophenylferrocene (Fig. 2). Reduction of
4%-formyl-4-biphenylferrocene using lithium aluminium
hydride provided 4%-hydroxymethyl-4-biphenylferrocene
in excellent yield. Another useful functional group that
was introduced to the ferrocenylbiphenyl group was the
NH2 group. Commercially available 3-nitroben-
zeneboronic acid was coupled with 4-bromophenylfer-
rocene and the resulting 3%-nitro-4-biphenylferrocene 6
was reduced by catalytic hydrogenation using a palla-
dium on charcoal catalyst.
The next stage of our study involved the synthesis of
arylferrocenylphenyl ethers and arylferrocenylphenyl
amines since we wanted to investigate the effect of the
ether and amine linkage on the thermal properties of
elongated ferrocene molecules. Reports have recently
appeared on the synthesis of diaryl ethers by the copper
acetate promoted coupling of arylboronic acids and
phenols [8]. Evans et al. reported good yields of diaryl
ethers by this reaction and it was found to be tolerant
of a wide range of substituents on both coupling part-
ners [8b]. Chan et al. extended the reaction to the
arylation of NꢁH containing compounds providing a
useful route to diarylamines [8c]. Simon et al. have
recently reported on the regioselective conversion of
arylboronic acids to phenols and subsequent coupling
to symmetrical diaryl ethers [8d].
In our first series of reactions, 4-ferrocenylphenol
was reacted with a range of substituted phenylboronic
,
acids in the presence of triethylamine, crushed 4 A
molecular sieves and copper(II) acetate catalyst. The
copper(II) acetate initially used was a hydrated form
which had been dried in a vacuum oven at ca. 200 °C
for 48 h prior to use. The isolated yields of the ethers
varied according to the nature of the substituent on the
phenylboronic acid (Table 2). Yields were generally
lower when the substituents were electron-withdrawing.
Fig. 2. Bophenylferrocene derivatives synthesized by the modified Suzuki method.

68
C. Imrie et al. / Journal of Organometallic Chemistry 645 (2002) 65–81
Table 2
Yield of arylferrocenylphenyl ethers from the reaction of 4-ferrocenylphenol and substituted phenylboronic acids
Entry
Substituent X
Yield (%) a
b,d
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
4-CH3
4-CH3
49
70
41
56
42
44
51
93
21
34
67
27
19
32
26
34
64
28
2
c
b,d
4-OCH3
4-OCH3
c
b,d
3,4,5-(OCH3)3
4-OCH2Ph b,d
4-H b,d
4-H c
b,d
4-OC8H17
4-F b,d
4-F c
3-F b,d
4-Br b,d
b,d
4-COCH3
4-CHO b,d
4-CHO b,e
4-CHO c
b,d
4-OCF3
b,d
4-CF3
b,e
3-NO2
10
a Yields are based on 4-ferrocenylphenol.
b Typical procedure: 4-ferrocenylphenol (one equivalent), anhydrous copper(II) acetate (one equivalent), the substituted phenylboronic acid (1.2
,
equivalents), powdered 4 A molecular sieves, and distilled triethylamine (five equivalents) were added to anhydrous dichloromethane. The reaction
mixture was allowed to stir at room temperature for 168 h.
c The procedure was as in b except that 98% copper(II) acetate was used (Aldrich Chemical Company).
d Reactions were carried out using 200 mg 4-ferrocenylphenol.
e Reactions were carried out using ca. 1 g 4-ferrocenylphenol.
2.3. Synthesis of arylferrocenylphenyl amines
The compounds of particular interest to us were those
with the potential for further functionalization at the
terminal position. 4-(4-Formylphenoxy)phenylferrocene
was prepared in a 26% isolated yield in the small scale
reaction. A 34% yield was obtained in a five fold larger
scale reaction.
In the second series of reactions, a different grade of
copper(II) acetate catalyst was used. It was a 98%
commercially available grade (Aldrich Chemical Com-
pany) and this catalyst led to a significant improvement
in the overall yields of the ether products (see entries 2,
8, 11 and 17 in Table 2).
Since by-products were generally observed, one reac-
tion, namely that between 4-ferrocenylphenol and 4-
methylbenzeneboronic acid was subjected to closer
scrutiny. The reaction mixture was analyzed by GC–
MS after filtration through a silica gel column to re-
move any inorganic components. The major com-
ponents were shown to be 4-(4-methylphenoxy)phenyl-
ferrocene and unreacted 4-ferrocenylphenol. Minor
components included p-cresol, 4,4%-dimethylbiphenyl
ether, 4,4%-dimethylbiphenyl and 4-acetoxytoluene.
Replacement of 4-ferrocenylphenol by 4-ferrocenyl-
aniline in the etherification reactions provided low
yields of arylferrocenylphenyl amines (Table 3). There
was evidence in these reactions for significant decompo-
sition of the ferrocenyl compounds which probably
accounts for the low overall yields and poor material
balances. Ferrocenes have previously been observed to
decompose in the presence of amines and other elec-
tron-donor molecules especially under oxidative condi-
tions where ferrocenium ions can be generated [9].
Attempts to synthesize the 4-formyl substituted deriva-
tive failed presumably due to the reactivity of the
formyl substituent to further attack by amine.
2.4. Crystal structure of 4%-formyl-4-biphenylferrocene
Crystals of 4%-formyl-4-biphenylferrocene 4 suitable
for X-ray crystallography were obtained from dichloro-
methane–hexane. The molecular structure of 4 together
with numbering scheme is shown in Fig. 3. The unit cell

C. Imrie et al. / Journal of Organometallic Chemistry 645 (2002) 65–81
69
is orthorhombic and the molecular geometry is ex-
tended and linear. The two cyclopentadienyl rings in
the ferrocenyl group are slightly staggered. Looking at
the cyclopentadienyl ring with the attached phenyl
chain from above, the unsubstituted cyclopentadienyl
ring is rotated clockwise by 13.5° with respect to the
substituted ring. This means that the conformation is
almost midway between the fully eclipsed (angle of
rotation 0°) and fully staggered (angle of rotation 36°).
With the long chain directed towards the viewer, the
first phenyl plane is rotated anticlockwise by 10.8° with
respect to the cyclopentadienyl plane. The second
phenyl plane is rotated anticlockwise by 27.8° with
respect to the first phenyl plane. Also, the chain is not
quite linear. The angle extending from the centroid of
the cyclopentadienyl ring to the centroids of the first
and second phenyl rings is 176.6°. The mean bond
distances are normal for this type of molecule, FeꢁC=
ment between molecules within a layer and between
layers. The molecules are arranged parallel to each
other in an extended fashion in a head-to-tail/tail-to-
head format. The only significantly short intermolecular
bond distance is between H(2) and O(1) and is 2.6054
,
A. All other intermolecular bond distances are well
beyond the range for hydrogen bonding (Table 4). H(2)
is in close contact with the ferrocenyl group and the
results suggest that there may be a considerable electro-
static interaction between the ferrocenyl group and the
aldehydic oxygen atom of another molecule. A similar
interaction has been reported by Sato et al. for fer-
rocenecarboxaldehyde in an investigation of the plastic
crystal phase of that molecule by X-ray diffraction [10].
This type of interaction has also been reported by
Ferguson et al. [11] in a-hydroxyferrocene derivatives.
2.5. Thermal properties of elongated biphenylferrocenes
,
,
2.03 A, CꢁC (five-membered rings)=1.40 A, CꢁC (six-
,
membered rings)=1.39 A, CꢁC (between rings)=1.48
A series of imines based on structures 7 and 8 were
synthesized. The compounds of series 7 were synthesized
,
A. The molecular packing of 4 emphasizes the arrange-
Table 3
Yield of arylferrocenylphenyl amines from the reaction of 4-ferrocenylaniline and substituted phenylboronic acids
Entry
Substituent X
Yield (%) a
b
1
2
3
4
4-CH3
4-CH3
14
21
3
c
b
4-OCH3
4-Br b
28
a Yields are based on 4-ferrocenylaniline.
b Typical procedure: 4-ferrocenylaniline (one equivalent), anhydrous copper(II) acetate (one equivalent), the substituted phenylboronic acid (1.2
,
equivalents), powdered 4 A molecular sieves (300 mg) and distilled triethylamine (five equivalents) was added to anhydrous dichloromethane. The
reaction was allowed to stir at room temperature for 168 h.
c Duplicate experiment.
Fig. 3. Molecular structure of 4%-formyl-4-biphenylferrocene with numbering scheme.

70
C. Imrie et al. / Journal of Organometallic Chemistry 645 (2002) 65–81
Table 4
effect of chain lengthening in relation to the lowering of
clearing temperatures is observed. A DSC curve is
shown in Fig. 4 for the compound where n=14 and the
enthalpies of transition for the compounds are provided
in Table 6. A graphical representation of the phase
distribution for series 7 is shown in Fig. 5. Compounds
in series 8 (n=5 and 14) were non-liquid crystalline
(melting points provided in Section 4).
,
Selected bond lengths (A) and selected bond angles (°) for compound
4
Bond lengths
C(2)ꢁC(3)
C(4)ꢁC(5)
C(6)ꢁC(10)
C(8)ꢁC(9)
C(9)ꢁC(11)
C(11)ꢁC(12)
C(13)ꢁC(14)
C(17)ꢁC(18)
C(20)ꢁC(21)
C(1)ꢁC(2)
C(14)ꢁC(15)
C(17)ꢁC(22)
C(20)ꢁC(23)
1.394(6)
1.410(7)
1.398(5)
1.418(5)
1.475(4)
1.392(4)
1.399(4)
1.391(4)
1.389(4)
1.388(8)
1.393(4)
1.406(4)
1.469(5)
C(3)ꢁC(4)
C(6)ꢁC(7)
C(7)ꢁC(8)
1.381(6)
1.388(6)
1.415(5)
1.431(4)
1.389(4)
1.376(4)
1.483(4)
1.388(5)
1.371(4)
1.418(7)
1.379(4)
1.386(4)
1.214(5)
C(9)ꢁC(10)
C(11)ꢁC(16)
C(12)ꢁC(13)
C(14)ꢁC(17)
C(18)ꢁC(19)
C(21)ꢁC(22)
C(1)ꢁC(5)
C(15)ꢁC(16)
C(19)ꢁC(20)
O(1)ꢁC(23)
Bond angles
C(8)ꢁC(9)ꢁC(11)
125.9(3)
C(10)ꢁC(9)ꢁC(11)
C(16)ꢁC(11)ꢁC(9)
C(13)ꢁC(12)ꢁC(11)
C(15)ꢁC(14)ꢁC(13)
128.2(3)
120.8(3)
122.0(3)
116.6(3)
C(16)ꢁC(11)ꢁC(12) 116.6(3)
C(12)ꢁC(11)ꢁC(9) 122.6(3)
C(12)ꢁC(13)ꢁC(14) 121.4(3)
by the reaction of 4%-formyl-4-biphenylferrocene 4 with
a series of n-alkoxyanilines. Series 8 were similarly
prepared starting from 4-(4-formylphenoxy)phenyl-
ferrocene.
For series 7, the compounds where n=8 and 14
exhibit enantiotropic smectic and nematic phases,
2.6. Structure-liquid crystal properties of elongated
ferrocenes
A compound requires two important criteria in order
to exhibit calamitic mesomorphism. Firstly, it should
have a long linear shape and secondly a large enough
length–depth (l/d) ratio so that significant intermolecu-
lar interactions can be generated. A conformational
search on a general structure of series 7 and 8 (n=1)
whereas the compound where n=5 exhibits
a
monotropic nematic phase (Table 5). The liquid crystal
domains in all cases are relatively short and the usual
Table 5
Phase transition temperatures and melting points of new ferrocenomesogens

C. Imrie et al. / Journal of Organometallic Chemistry 645 (2002) 65–81
71
Fig. 4. Dsc curve for a compound of series 7.
was performed and compared with results for other
elongated ferrocenyl molecules prepared by us previ-
ously [12] (series 9, 10, 11 and 12) (Fig. 6). In order to
minimize computational times, the n-alkoxy chains
were kept short (we used methoxy- or methoxycarbonyl-
oxy). Calculation of the l/d ratios however, was carried
out for molecules containing an n-octyloxy chain since
these derivatives are liquid crystalline in series, 7, 9 and
10 but not in series 11 and 12. The assumption was
made that the n-octyloxy chains would adopt relatively
linear conformations. The MM+ calculations were
based on the atomic charges in each molecule, as
calculated earlier from a ZINDO-1 single-point calcula-
tion on the initial structures. The lowest energy ge-
ometries of these conformers which resulted were then
further optimized at the ZINDO-1 semi-empirical MO
level. It is clear from the results in Table 7 that mono-
substituted ferrocenomesogens have a much larger l/d
ratio than non-liquid-crystalline elongated ferrocenes.
Table 6
The enthalpies of transition (DH[J g−1]) for the compounds of series
7
n
K“Sx K“I Sx“N N“I I“N N“Sx N“K Sx“K
5
8
14
36.7
1.5
1.3
1.3
22.9
31.5
4.6
31.5
15.9
1.2
0.97
22.6
18.5
NS
5.0
Abbreviations: K, crystalline; Sx, unidentified smectic phase; N, ne-
matic phase; I, isotropic liquid; NS, observed by optical microscopy
only.

72
C. Imrie et al. / Journal of Organometallic Chemistry 645 (2002) 65–81
Fig. 5. Phase distribution of compounds in series 7.
Deschenaux and co-workers reported that 1,3-disubsti-
tuted ferrocenomesogens [13] have an l/d ratio greater
than 5. The lowest energy conformations of the non-
mesogenic 8, 11 and 12 show pronounced kinks in the
molecular structures that result in lower l/d ratios.
dry nitrogen. Silica gel 50 or Al2O3 (active, neutral,
Brockmann Grade I) were used for column chromatog-
raphy. Thin layer preparative chromatography was car-
ried out on plates using Merck silica gel 60 F254 (1.5
mm) as adsorbent. M.p. were recorded on an Elec-
trothermal IA 900 series digital m.p. apparatus and
are uncorrected. Infrared spectra were recorded on a
Perkin–Elmer 1600 series Fourier Transform IR spec-
3. Conclusion
The synthesis of a series of substituted biphenylfer-
rocenes using a modified Suzuki cross-coupling reaction
has been achieved. The biphenylferrocenes were ob-
tained in high yield. The X-ray crystal structure of
4%-formyl-4-biphenylferrocene was obtained and it pro-
vided evidence of intermolecular hydrogen bonding be-
tween molecules. This molecule was further extended by
reaction with n-alkoxyanilines to provide the first series
of ferrocenomesogens with a terminal biphenylferrocene
group. The first synthesis of arylferrocenylphenyl ethers
was achieved by the reaction of 4-ferrocenylphenol with
substituted phenylboronic acids. The initial yields of
these molecules using an oven dried copper(II) acetate
catalyst were low but were significantly improved by
using 98% copper(II) acetate (Aldrich Chemical Com-
pany). The synthesis of arylferrocenylphenyl amines was
similarly achieved by the reaction of 4-ferrocenylaniline
and substituted phenylboronic acids.
4. Experimental
4.1. Purification and characterization of the materials
All reactions were performed under an atmosphere of
Fig. 6. The optimized geometries of elongated monosubstituted ferro-
cenyl derivatives.

C. Imrie et al. / Journal of Organometallic Chemistry 645 (2002) 65–81
73
Table 7
whereas CH2Cl2–EtOH denotes that CH2Cl2 was used
to dissolve the solid and the slow addition of EtOH
resulted in crystallization. All solvents that required
distillation, were distilled directly into the reaction flask
to be used, under nitrogen.
Approximate length–depth ratios of elongated ferrocenyl derivatives
a
,
Compound
l/d (A)
7
9
10
11
12
8
6
6
2
2
4.2. Preparation of substituted biphenylferrocenes
4.2.1. 4%-Methoxy-4-biphenylferrocene
a l/d ratios calculated for the OC8H17 derivative of each series.
To 90% EtOH (150 cm3), which was purged with
nitrogen for 24 h, deaerated by the freeze-thaw method
(3 cycles) and purged further with nitrogen for another
24 h, was added 4-methoxybenzeneboronic acid (445
mg, 2.9 mmol), 4-bromophenylferrocene (500 mg, 1.5
mmol), Ba(OH)2 (650 mg, 2.1 mmol) and palladium(II)
acetate (110 mg, 0.49 mmol) under nitrogen. The reac-
tion mixture was vigorously shaken for 30 min and then
allowed to stir for 2 weeks under nitrogen at r.t.
Thereupon, the solvent was removed in vacuo, the
residue taken up in CH2Cl2 and filtered. The organic
extracts were then washed with water prior to drying
over anhydrous Na2SO4. The solvent was removed in
vacuo and the residue was chromatographed through a
flash silica gel column. Elution with C6H14 afforded
unreacted 4-bromophenylferrocene (36 mg, 93% con-
version) which was characterized as described earlier.
Elution with C6H14–CH2Cl2 (1:1) stripped the column,
and this residue was subjected to plate chromatography
on silica gel. Elution with C6H14–CH2Cl2 (7:3) afforded
4%-methoxy-4-biphenylferrocene (504 mg, 93%) as or-
ange crystals (from CH2Cl2–C6H14 in the cold), m.p.
190–192 °C; IR (KBr cm−1) 1605, 1578, 1454, 1440,
1404, 1306, 1289, 1252, 1179, 1104, 1033, 998, 886, 827,
trometer as KBr discs or as solutions in chloroform.
1H- and 13C-NMR spectra were recorded on a Bruker
Avance 300 MHz spectrometer as solution in CDCl3 or
Me2SO using tetramethylsilane (TMS) as internal stan-
dard. Mass spectra were recorded on a VG70-SEQ/
MSSMS2 spectrometer at the Cape Technikon.
Microanalyses were performed on a Carlo-Erba MOD
1160 elemental analyzer by the Council for Scientific
and Industrial Research, Pretoria and at the University
of Cape Town. Crystal X-ray crystallography was per-
formed on a Bruker/AXS SMART-CCD diffractometer
at the Department of Chemistry, University of the
Witwatersrand, Johannesburg. Transition temperatures
of the liquid crystal molecules were investigated by
differential scanning calorimetry (DSC) utilizing a Du
Pont 910 DSC cell, connected to a Du Pont 9000
Thermal Analyser. Compounds were studied at various
scanning rates (2.5, 5 or 10 °C min−1) for both the
heating and cooling cycles, after being encapsulated in
aluminium pans. An empty aluminium pan served as
the reference. The calorimeter was calibrated with an
indium standard. The textures of the mesophases were
studied with a standard Zeiss polarizing microscope
equipped with a Reichert hot stage at UPE and with a
Nikon Eclipse E600 optical polarizing microscope
equipped with a Linkam heating–freezing stage linked
to a Linkam range TMS 93 precision temperature
control at Rhodes University, Grahamstown. Reaction
mixtures were shaken on a Griffin flask shaker (896331/
2). The GC–MS work was carried out using a HP5972
Series mass selective detector coupled with a HP Series
1
713; H-NMR (CDCl3) 7.56 (2H, d, J 8.8, ArH), 7.51
(2H, s, ArH), 7.48 (2H, d, J 8.8, ArH), 6.98 (2H, d, J
8.8, ArH), 4.67 (2H, t, J 1.8, C5H4), 4.33 (2H, t, J 1.8,
C5H4), 4.07 (5H, s, C5H5), 3.86 (3H, s, OCH3); 13C-
NMR (CDCl3) 159.00, 138.24, 137.70, 133.51, 127.78,
126.55, 126.47, 114.22, 85.16, 69.61, 68.92, 66.45, 55.35;
m/z 369 (27%), 368 [M+, 100], 366 (7), 353 (10), 326
(5), 325 (21), 204 (6), 202 (5), 184 (9), 120 (9). Anal.
Calc. for C23H20FeO: C, 75.0; H, 5.5; [M], 368.08635.
Found: C, 74.8, H, 5.7%, [M+], 368.08580.
25890 spectrometer. The column used was
a
Chrompack HP1 (30 m×0.32×0.25 mm). The major-
ity of the phenylboronic acids and palladium(II) acetate
(99%) were purchased from Lancaster Synthesis (UK)
and were used without further purification The cop-
per(II) acetate catalyst used in the etherification reac-
tions was either hydrated copper(II) acetate dried in a
vacuum oven at 200 °C for 48 h or copper(II) acetate
(98%) purchased from the Aldrich Chemical Company
(USA). Unless otherwise stated all recrystallizations
were performed at room temperature (r.t.). If more
than one solvent was used to perform the recrystalliza-
tion, two different annotations are used, e.g. CH2Cl2/
EtOH denotes that a mixture of two solvents was used,
4.2.2. 4%-Methyl-4-biphenylferrocene
Quantities: 4-methylbenzeneboronic acid (399 mg,
2.9 mmol), 4-bromophenylferrocene (500 mg, 1.5
mmol), Ba(OH)2 (650 mg, 2.1 mmol) and palladium(II)
acetate (110 mg, 0.49 mmol). The experimental proce-
dure was as described for 4%-methoxy-4-biphenylfer-
rocene. 4%-Methyl-4-biphenylferrocene (457 mg, 88%)
was obtained as orange crystals (from CH2Cl2–C6H14
in the cold), m.p. 184–185 °C; IR (KBr cm−1) 1509,
1452, 1402, 1104, 1087, 1032, 1001, 886, 813, 735;
1H-NMR (CDCl3) 7.52 (6H, m, ArH), 7.26 (2H, d, J
7.9, ArH), 4.67 (2H, t, J 1.8, C5H4), 4.33 (2H, t, J 1.8,

74
C. Imrie et al. / Journal of Organometallic Chemistry 645 (2002) 65–81
C5H4), 4.07 (5H, s, C5H5), 2.40 (3H, s, CH3); 13C-NMR
(CDCl3) 138.54, 138.04, 136.79, 129.49, 126.78, 126.60,
126.45, 85.13, 69.62, 68.95, 66.48, 21.11; m/z 353 (27%),
352 [M+, 100], 351 (5), 350 (8), 231 (7), 215 (5), 176 (6),
121 (7). Anal. Calc. for C23H20Fe: C, 78.4; H, 5.7; [M],
352.09144. Found: C, 77.9; H, 6.0%; [M+], 352.09292.
ferrocene with the exception that the reaction mixture
was heated under reflux for 7×7 h during the reaction
time of 504 h, and that the product was eluted with
CH2Cl2–C6H14 (3:2). 4-Bromophenylferrocene (175 mg,
83% conversion) was obtained and 4%-formyl-4-
biphenylferrocene (537 mg, 50%) as red crystals (from
CH2Cl2–C6H14 in the cold), m.p. 194–195 °C; IR (KBr
cm−1) 1696, 1599, 1531, 1403, 1384, 1306, 1280, 1217,
1189, 1167, 1104, 1085, 1030, 1002, 887, 815, 739;
1H-NMR (CDCl3) 10.06 (1H, s, CHO), 7.96 (2H, d, J
8.2, ArH), 7.79 (2H, d, J 8.2, ArH), 7.58 (4H, s, ArH),
4.71 (2H, t, J 1.8, C5H4), 4.37 (2H, t, J 1.8, C5H4), 4.07
(5H, s, C5H5); 13C-NMR (CDCl3) 191.90, 146.91,
140.15, 136.88, 135.00, 130.34, 127.27, 127.19, 126.61,
84.40, 69.76, 69.36, 66.63; m/z 368 (6%), 367 (36), 366
[M+, 100], 364 (10). Anal. Calc. for C23H18FeO: C,
75.4; H, 5.0; [M], 366.07070. Found: C, 75.3; H, 4.9%;
[M+], 366.07002.
4.2.3. 4%-Octyloxy-4-biphenylferrocene
Quantities: 4-octyloxybenzeneboronic acid (734 mg,
2.9 mmol), 4-bromophenylferrocene (500 mg, 1.5
mmol), Ba(OH)2 (647 mg, 2.01 mmol) and palladi-
um(II) acetate (110 mg, 0.49 mmol). The experimental
procedure was as described for 4%-methoxy-4-biphenyl-
ferrocene. 4-Bromophenylferrocene (93 mg, 81% con-
version) was obtained which was characterized as
described earlier and 4%-octyloxy-4-biphenylferrocene
(446 mg, 65%) as orange crystals (from CH2Cl2–C6H14
in the cold), m.p. 136 °C; IR (KBr cm−1) 2954–2864
(br.), 1912, 1886, 1606, 1578, 1501, 1474, 1393, 1250,
1178, 1104, 1033, 995, 824, 721; 1H-NMR (CDCl3)
7.57–7.45 (6H, m, ArH), 6.92 (2H, t, J 8.4, ArH), 4.63
(2H, t, J 1.8, C5H4), 4.28 (2H, t, J 1.8, C5H4), 4.03 (5H,
s, C5H5), 3.95 (3H, t, J 6.6, OCH2), 1.77 (2H, m, CH2),
1.44–1.29 (10H, m, 5×CH2), 0.89 (3H, s, CH3); 13C-
NMR (CDCl3) 158.61, 138.34, 137.61, 133.27, 127.74,
127.66, 126.52, 126.47, 114.81, 114.75, 85.26, 69.64,
68.93, 68.12, 66.47, 31.84, 29.39, 29.33, 29.27, 26.09,
22.68, 14.12; m/z 467 (35%), 466 [M+, 100], 464 (7), 411
(8), 354 (9), 353 (7), 323 (8), 186 (12). Anal. Calc. for
C30H34FeO: C, 77.3; H, 7.3; [M] 466.19591. Found: C,
77.8; H, 8.0%; [M+], 466.19685.
4.2.5.2. Reaction 2. Quantities: 4-formylbenzeneboronic
acid (0.88 g, 5.9 mmol), 4-bromophenylferrocene (1.00
g, 2.9 mmol), Ba(OH)2 (1.30 g, 4.1 mmol) and palladi-
um(II) acetate (0.22 g, 0.98 mmol). The experimental
procedure was as described for 4%-methoxy-4-biphenyl-
ferrocene with the exception that the reaction time was
768 h. Yield of 4%-formyl-4-biphenylferrocene (0.14 g,
13%).
4.2.5.3. Reaction 3. Quantities: 4-formylbenzeneboronic
acid (0.88 g, 5.9 mmol), 4-bromophenylferrocene (1.00
g, 2.9 mmol), Ba(OH)2 (1.30 g, 4.1 mmol) and palladi-
um(II) acetate (0.22 g, 0.98 mmol). The experimental
procedure was as described for 4%-methoxy-4-biphenyl-
ferrocene with the exception that the reaction time was
24 h. 4-Bromophenylferrocene (0.61 g, 39% conversion)
and 4%-formyl-4-biphenylferrocene (0.11 g, 10%) were
obtained.
4.2.4. 4-Biphenylferrocene
Quantities: benzeneboronic acid (357 mg, 2.9 mmol),
4-bromophenylferrocene (500 mg, 1.5 mmol), Ba(OH)2
(647 mg, 2.1 mmol) and palladium(II) acetate (110 mg,
0.49 mmol). The experimental procedure was as de-
scribed for 4%-methoxy-4-biphenylferrocene. 4-Bro-
mophenylferrocene (98 mg, 80% conversion) was
obtained and 4-biphenylferrocene (391 mg, 79%) as
orange crystals (from C6H14), m.p. 160 °C ([4] 164–
165 °C); IR (KBr cm−1) 3097, 3028, 2962, 1714, 1597,
1535, 1492, 1451, 1409, 1262, 1206, 1103, 1085, 1029,
4.2.6. 4%-Hydroxymethyl-4-biphenylferrocene
A round-bottomed flask was charged with lithium
aluminium hydride (LAH) (16 mg, 0.41 mmol) in anhy-
drous Et2O (50 cm3). The solution was stirred and
treated with an ethereal solution of 4%-formyl-4-
biphenylferrocene (150 mg, 0.41 mmol), and then
heated under reflux for 2 h. Excess LAH was destroyed
by addition of EtOAc, and the reaction mixture was
then carefully added to an ice-water slurry. The organic
layer was separated and washed twice with water, dried
over anhydrous Na2SO4, and then evaporated to dry-
ness. The orange residue was then subjected to column
chromatography on silica gel. Dichloromethane was
used to elute 4%-hydroxymethyl-4-biphenylferrocene
which was recrystallized from an EtOH–CH2Cl2 mix-
ture in the cold (144 mg, 95%), m.p. 185–187 °C; IR
(KBr cm−1) 3564, 3112, 3048, 2952, 2871, 1919, 1610,
1546, 1514, 1457, 1424, 1384, 1286, 1214, 1116, 1091,
1
1001, 885, 841, 807; H-NMR (CDCl3) 7.64 (2H, m,
ArH), 7.55 (3H, s, ArH), 7.42 (4H, m, ArH), 4.69 (2H,
t, J 1.9, C5H4), 4.35 (2H, t, J 1.9, C5H4), 4.08 (5H, s,
C5H5); m/z 339 (26%), 338 [M+, 100], 336 (8), 306 (12),
305 (10), 273 (22), 215 (18).
4.2.5. 4%-Formyl-4-biphenylferrocene
4.2.5.1. Reaction 1. Quantities: 4-formylbenzeneboronic
acid (0.88 g, 5.9 mmol), 4-bromophenylferrocene (1.00
g, 2.9 mmol), Ba(OH)2 (1.30 g, 4.1 mmol) and palladi-
um(II) acetate (0.22 g, 0.98 mmol). The experimental
procedure was as described for 4%-methoxy-4-biphenyl-
1
1043, 1010, 897, 824, 743, 654, 630; H-NMR (CDCl3)

C. Imrie et al. / Journal of Organometallic Chemistry 645 (2002) 65–81
75
7.63 (2H, d, J 8.1, ArH), 7.53 (4H, m, ArH), 7.45 (2H,
d, J 8.3, ArH), 4.74 (2H, s, CH2), 4.68 (2H, t, J 1.9,
C5H4), 4.34 (2H, t, J 1.9, C5H4), 4.07 (5H, s, C5H5);
13C-NMR (CDCl3) 140.38, 139.66, 138.55, 138.18,
127.52, 126.94, 126.51, 85.11, 69.67, 69.06, 66.54,
65.17; m/z 369 (26%), 368 [M+, 100], 367 (6), 366 (19),
231 (7), 230 (35). Anal. Calc. for C23H20FeO: C, 75.0;
H, 5.5; [M], 368.08635. Found: C, 74.5; H, 5.6%; [M+
], 368.08633.
mmol), Ba(OH)2 (650 mg, 2.1 mmol) and palladium(II)
acetate (110 mg, 0.49 mmol). The experimental proce-
dure was as described for 4%-methoxy-4-biphenylfer-
rocene. Yield of 4%-benzyloxy-4-biphenylferrocene (600
mg, 70%), m.p. 210–212 °C; IR (KBr cm−1) 3091,
3040, 2911, 1609, 1506, 1471, 1377, 1283, 1180, 1103,
1
1060, 837, 649, 503; H-NMR (CDCl3) 7.44 (11H, m,
ArH), 7.04 (2H, dd, J 8.8, ArH), 5.12 (2H, s, CH2),
4.67 (2H, t, J 1.8, C5H4), 4.33 (2H, t, J 1.8, C5H4),
4.06 (5H, s, C5H5); 13C-NMR (CDCl3) 158.22, 157.93,
138.19, 137.74, 137.00, 133.76, 128.62, 127.99, 127.80,
127.75, 127.50, 126.56, 126.47, 115.17, 115.11, 85.14,
70.09, 69.61, 68.93, 66.45; m/z 446 (3), 445 (20), 444
[M+, 59], 442 (4), 367 (9), 366 (33), 354 (10), 353 (38),
326 (5), 325 (19), 276 (4), 275 (15), 121 (5), 91 (100).
Anal. Calc. for C29H24FeO: [M], 444.11765. Found:
[M+], 444.11771.
4.2.7. 4%-Fluoro-4-biphenylferrocene
Quantities: 4-fluorobenzeneboronic acid (0.82 g, 5.9
mmol), 4-bromophenylferrocene (1.00 g, 2.9 mmol),
Ba(OH)2 (1.30 g, 4.1 mmol) and palladium(II) acetate
(0.22 g, 0.98 mmol). The experimental procedure was
as described for 4%-methoxy-4-biphenylferrocene. Yield
of 4%-fluoro-4-biphenylferrocene (0.93 g, 89%) as or-
ange crystals (from CH2Cl2–C6H14 in the cold), m.p.
189–190 °C; IR (KBr cm−1) 1595, 1505, 1454, 1398,
4.2.10. 4%-Hydroxy-4-biphenylferrocene
1
1239, 1200, 1163, 1106, 1030, 1001, 890, 821; H-NMR
4-Benzyloxy-4%-biphenylferrocene (250 mg, 0.563
mmol) was placed in a Parr hydrogenation reactor
together with deaerated EtOH (200 cm3), anhydrous
THF (200 cm3), and 10% palladium on charcoal (1.0
g). The reactor was purged with hydrogen and the
mixture was allowed to stir under hydrogen for 76 h.
The reaction was monitored by tlc which showed that
unreacted starting material was still present. A further
batch of catalyst and hydrogen was added and the
reaction continued for another 48 h. The residual pal-
ladium was filtered off and the solvent removed in
vacuo. The residue was then subjected to column chro-
matography on silica gel and the product was isolated
as a yellow solid (48 mg, 24%), m.p. 173–174 °C; IR
(KBr cm−1) 3590, 3240, 2920, 2840, 1596, 1461, 1410,
(CDCl3) 7.58 (2H, d, J 8.7, ArH), 7.54 (2H, d, J 8.0,
ArH), 7.47 (2H, d, J 8.4, ArH), 7.13 (2H, t, J 8.7),
4.68 (2H, t, J 1.8, C5H4), 4.34 (2H, t, J 1.8, C5H4),
4.07 (5H, s, C5H5); 13C-NMR (CDCl3) 138.47, 137.60,
128.34, 126.86, 126.51, 115.77, 115.48, 84.86, 69.65,
69.06, 66.51; m/z 357 (26%), 356 [M+, 100], 354 (8),
235 (11), 233 (5), 178 (5), 120 (13). Anal. Calc. for
C22H17FFe: C, 74.2; H, 4.8; [M], 356.06637. Found: C,
74.0; H, 4.8%; [M+], 356.06579.
4.2.8. 4%-Acetyl-4-biphenylferrocene
Quantities: 4-acetylbenezeneboronic acid (0.95 g,
5.80 mmol), 4-bromophenylferrocene (1.00 g, 2.90
mmol), Ba(OH)2 (1.30 g, 4.1 mmol) and palladium(II)
acetate (0.22 g, 0.98 mmol). The experimental proce-
dure was as described for 4%-methoxy-4-biphenylfer-
rocene except that the reaction mixture was heated
under reflux for 3×7 h during the reaction period.
4-Bromophenylferrocene (0.098 g, 90% conversion)
was obtained and 4%-acetyl-4-biphenylferrocene (0.160
g, 14%) as red crystals (from C6H14), m.p. 196–
198 °C; IR (KBr cm−1) 1692, 1617, 1412, 1380, 1283,
1
1380, 1255, 1175, 1100, 1011, 820, 730, 515, 490; H-
NMR (CDCl3) 7.48 (6H, m, ArH), 6.95 (2H, d, J 8.5,
ArH), 4.86 (1H, s, OH), 4.73 (2H, t, J 1.8 C5H4), 4.39
(2H, t, J 1.8 C5H4), 4.11 (5H, s, C5H5); 13C-NMR
(CDCl3) 155.37, 138.57, 138.14, 134.12, 128.40, 126.92,
126.85, 116.06, 85.53, 69.99, 69.32, 66.84; m/z 356 (4),
355 (26), 354 [M+, 100], 353 (4), 352 (7), 121 (7). Anal.
Calc. for C22H18FeO: [M], 354.07070. Found: [M+],
354.07079.
1
971, 831, 604; H-NMR (CDCl3) 8.04 (2H, d, J 8.3,
ArH), 7.72 (2H, d, J 8.3, ArH), 7.57 (4H, s, ArH),
4.69 (2H, t, J 1.8, C5H4), 4.36 (2H, t, J 1.8, C5H4),
4.07 (5H, s, C5H5), 2.64 (3H, s, CH3); 13C-NMR
(CDCl3) 197.79, 145.49, 139.80, 137.06, 135.60, 128.99,
127.16, 126.74, 126.56, 84.45, 69.84, 69.69, 69.25,
66.58; m/z 380 [M+, 5%], 239 (7), 238 (41), 224 (16),
223 (100), 153 (6), 152 (19), 151 (9), 43 (56). Anal.
Calc. for C24H20OFe: C, 75.8; H, 5.3; [M], 380.08635.
Found: C, 76.4; H, 5.6%; [M+], 380.08550.
4.2.11. 4%-Hydroxy-4-biphenylferrocene from the
reaction of 4-bromophenylferrocene and
4-hydroxyphenylboronic acid
Quantities: 4-hydroxybenzeneboronic acid (163 mg,
1.17 mmol), 4-bromophenylferrocene (267 mg, 0.587
mmol), Ba(OH)2 (270 mg, 0.42 mmol), and palladi-
um(II) acetate (47 mg, 0.098 mmol). The experimental
procedure was as described for 4%-methoxy-4-biphenyl-
ferrocene. The product was obtained as a yellow solid
(72 mg, 33%) and the characterization was the same as
described in Section 4.2.10.
4.2.9. 4%-Benzyloxy-4-biphenylferrocene
Quantities: 4-benzyloxybenzeneboronic acid (478
mg, 2.9 mmol), 4-bromophenylferrocene (500 mg, 1.5

76
C. Imrie et al. / Journal of Organometallic Chemistry 645 (2002) 65–81
4.2.12. 3%-Nitro-4-biphenylferrocene
anhydrous CH2Cl2 (20 cm3) and Et3N (364 mg, 3.60
mmol). The reaction mixture was allowed to stir at r.t.
for 168 h during which time its color darkened. The
reaction mixture was then filtered and the filtrate was
passed through a column of silica gel eluting with Et2O
and this removed any inorganic materials. The solvent
was removed in vacuo and the residue was then sub-
jected to flash chromatography on silica gel. In most
cases, the arylferrocenylphenyl ether was eluted from
the column using a C6H14–CH2Cl2 (1:1) mixture but in
cases where the substituent group was more polar
(CHO, COCH3), CH2Cl2 was used on its own. Unre-
acted starting material remained behind on the column.
The arylferrocenylphenyl ether was then subjected to
further purification on a TLC preparative plate and
again elution was carried out using C6H14–CH2Cl2.
Extraction from the silica gel material with CH2Cl2 and
final evaporation of the solvent left in most cases
orange solids.
Quantities: 3-nitrobenzeneboronic acid (1.25 g, 7.5
mmol), 4-bromophenylferrocene (1.0 g, 2.9 mmol),
Ba(OH)2 (1.67 g, 5.25 mmol), and palladium(II) acetate
(0.28 g, 1.25 mmol). The experimental procedure was as
described for 4%-methoxy-4-biphenylferrocene except
that the reaction mixture was heated intermittently
under reflux during the reaction period (14×8 h). The
product was obtained as a red–orange solid (0.42 g,
38%), m.p. 163–164 °C; IR (KBr cm−1) 3083, 2853,
1607, 1522, 1348, 1282, 1105, 1083, 999, 887, 835, 818,
772, 726, 679; 501; 1H-NMR (CDCl3) 8.41 (1H, t, J 1.9,
ArH), 8.12 (1H, m, ArH), 7.87 (1H, m, ArH), 7.51 (5H,
m, ArH), 4.63 (2H, t, J 1.8, C5H4), 4.30 (2H, t, J 1.8,
C5H4), 4.00 (5H, s, C5H5); 13C-NMR (CDCl3) 149.20,
143.03, 140.57, 136.26, 132.98, 130.10, 127.45, 127.09,
122.14, 121.93, 84.57, 70.10, 69.72, 69.40, 66.99; m/z
384 (32), 383 [M+, 100], 337 (27), 215 (17), 185 (17),
121 (7). Anal. Calc. for C22H17FeNO2: C, 68.9; H, 4.5;
N, 3.6; [M], 383.0620. Found: C, 68.3; H, 4.7; N, 3.3%;
[M+], 383.0609.
4.3.1. 4-(4-Methylphenoxy)phenylferrocene
The reaction yielded the product as orange crystals
(130 mg, 49%), m.p. 76–78 °C; IR (KBr cm−1) 3075,
3019, 2912, 1605, 1504, 1453, 1273, 1239, 1160, 1104,
4.2.13. 3%-Amino-4-biphenylferrocene
A mixture of 3%-nitro-4-biphenylferrocene (150 mg,
0.46 mmol), 10% Pd/C (500 mg) and THF (500 cm3)
was placed in a Parr hydrogenation reactor. The reac-
tor was purged with hydrogen and then the mixture was
allowed to stirr under hydrogen for 72 h. The solution
was filtered through celite and concentrated to leave a
brown oily residue. The residue was passed through a
column of silica gel. Unreacted starting material was
first removed using C6H14–CH2Cl2 and the product was
eluted as an orange band using CH2Cl2. Removal of the
solvent from the second orange band left yellow crys-
tals identified as 3%-amino-4-biphenylferrocene (121 mg,
89%), m.p. 125–126 °C; IR (KBr cm−1) 3446, 3365,
3089, 2922, 1618, 1530, 1492, 1455, 1406, 1313, 1227,
1104, 1000, 834, 780, 698, 497; 1H-NMR (CDCl3) 7.52–
7.43 (4H, m, ArH), 7.22 (1H, d, J 7.8, ArH), 7.02 (1H,
m, ArH), 6.93 (1H, m, ArH), 6.67 (1H, m, ArH), 4.67
(2H, t, J 1.8, C5H4), 4.33 (2H, t, J 1.8, C5H4), 4.06 (5H,
s, C5H5); 13C-NMR (CDCl3) 147.10, 142.54, 139.16,
138.74, 130.09, 127.35, 126.76, 117.77, 114.36, 113.94,
85.47, 70.18, 69.37, 66.89; m/z 353 [M+, 100], 352 (5),
351 (8), 232 (9), 176 (11). Anal. Calc. for C22H19FeN:
C, 74.8, H, 5.4; N, 4.0; [M], 353.08669. Found: C, 75.1,
H, 6.6; N, 3.5%; [M+], 353.08572.
1
884, 834, 523, 501; H-NMR (CDCl3) 7.41 (2H, d, J 8.8
ArH), 7.15 (2H, d, J 8.2, ArH), 6.94 (2H, d, J 8.1,
ArH), 6.91 (2H, d, J 8.6, ArH), 4.58 (2H, t, J 1.8,
C5H4), 4.28 (2H, t, J 1.8, C5H4), 4.05 (5H, s, C5H5),
2.34 (3H, s, CH3); 13C-NMR (CDCl3) 155.99, 154.86,
133.76, 132.78, 130.21, 127.29, 118.94, 118.38, 85.37,
69.53, 68.69, 66.31, 20.71; m/z 370 (4), 369 (27), 368
[M+, 100], 121 (6). Anal. Calc. for C23H20FeO: C, 75.1;
H, 5.5; [M], 368.08635. Found: C, 74.9, H, 5.8%; [M+],
368.08676.
4.3.2. 4-(4-Methoxyphenoxy)phenylferrocene
The reaction yielded the product as orange crystals
(113 mg, 41%), m.p. 94–96 °C; IR (KBr cm−1) 3091,
2983, 2954, 1530, 1497, 1451, 1288, 1242, 1105, 1034,
1
883, 831, 629, 570; H-NMR (CDCl3) 7.40 (2H, d, J
8.7, ArH), 7.00 (2H, d, J 9.1, ArH), 6.89 (2H, d, J 9.1,
ArH), 6.87 (2H, d, J 8.7, ArH), 4.57 (2H, t, J 1.8,
C5H4), 4.28 (2H, t, J 1.8, C5H4), 4.04 (5H, s, C5H5),
3.81 (3H, s, OCH3); 13C-NMR (CDCl3) 156.73, 155.81,
150.29, 133.35, 127.26, 120.65, 117.62, 114.84, 85.42,
69.51, 68.65, 66.28, 55.67; m/z 385 (28), 384 [M+, 100],
262 (4), 261 (18), 192 (6), 121 (6). Anal. Calc. for
C23H20FeO2: C, 71.9; H, 5.2; [M], 384.08127. Found: C,
71.9; H, 5.1%; [M+], 384.08205.
4.3. Preparation of arylferrocenylphenyl ethers. General
method
4.3.3. 4-Phenoxyphenylferrocene
To a 100 cm3 round-bottomed flask was added 4-fer-
rocenylphenol (200 mg, 0.72 mmol), anhydrous cop-
per(II) acetate (131 mg, 0.72 mmol), the substituted
The reaction yielded the product as orange crystals
(130 mg, 51%), m.p. 129–130 °C; IR (KBr cm−1
)
2919, 1590, 1519, 1490, 1449, 1290, 1243, 1167, 1102,
1073, 1002, 885, 850, 814, 761, 691, 520, 497; H-NMR
(CDCl3) 7.44 (2H, d, J 8.7, ArH), 7.35 (2H, t, J 7.6,
1
,
arylboronic acid (0.86 mmol) and dried powdered 4 A
molecular sieves (300 mg). To this mixture was added

C. Imrie et al. / Journal of Organometallic Chemistry 645 (2002) 65–81
77
ArH), 7.10 (1H, t, J 7.6, ArH), 7.03 (2H, d, J 8.7,
4.3.7. 4-(4-Formylphenoxy)phenylferrocene
ArH), 6.95 (2H, d, J 8.7, ArH), 4.59 (2H, t, J 1.8,
C5H4), 4.29 (2H, t, J 1.8, C5H4), 4.05 (5H, s, C5H5);
13C-NMR (CDCl3) 157.39, 155.37, 134.24, 129.72,
127.34, 123.09, 118.93, 118.69, 85.25, 69.55, 68.75,
66.34; m/z 355 (26), 354 [M+, 100], 352 (6), 121 (8).
Anal. Calc. for C22H18FeO: [M], 354.07070. Found:
[M+], 354.0716.
4.3.7.1. Reaction 1. Smaller scale reaction. The reaction
yielded the product as red crystals (72 mg, 26%), m.p.
107–109 °C; IR (KBr cm−1) 1702, 1595, 1501, 1453,
1388, 1305, 1252, 1158, 1110, 1009, 856, 820, 542, 471;
1H-NMR (CDCl3) 9.92 (1H, s, CHO), 7.85 (2H, d, J
8.8, ArH), 7.50 (2H, d, J 8.7, ArH), 7.08 (2H, d, J 8.7,
ArH), 7.01 (2H, d, J 8.7, ArH), 4.62 (2H, t, J 1.8,
C5H4), 4.32 (2H, t, J 1.8, C5H4), 4.06 (5H, s, C5H5);
13C-NMR (CDCl3) 190.78, 163.33, 153.10, 136.24,
131.97, 131.19, 127.62, 120.39, 117.45, 84.64, 69.61,
69.02, 66.46; m/z 383 (27), 382 [M+, 100], 277 (2), 267
(4), 261 (2), 191 (4), 190 (12), 149 (18), 121 (15). Anal.
Calc. for C23H18FeO2: C, 72.3; H, 4.7; [M], 382.06562.
Found: C, 72.5; H, 5.0%; [M+], 382.06442.
4.3.4. 4-(4-Fluorophenoxy)phenylferrocene
The reaction yielded the product as orange crystals
(90 mg, 34%), m.p. 113–115 °C; IR (KBr cm−1) 3074,
2921, 1530, 1497, 1451, 1295, 1256, 1216, 1105, 1031,
999, 890, 831, 815, 753, 720, 550, 511; 1H-NMR
(CDCl3) 7.42 (2H, d, J 8.8, ArH), 7.02 (4H, m, ArH),
6.90 (2H, d, J 8.8, ArH), 4.59 (2H, t, J 1.7, C5H4), 4.29
(2H, t, J 1.7, C5H4), 4.05 (5H, s, C5H5); 13C-NMR
(CDCl3) 160.74, 157.54, 156.23, 153.41, 134.58, 127.77,
120.79, 120.68, 118.70, 116.80, 116.50, 85.55, 69.94,
69.17, 66.73; m/z 373 (26), 372 [M+, 100], 277 (3), 261
(3), 186 (6), 121 (11). Anal. Calc. for C22H17FFeO: C,
71.0; H, 4.6%; [M], 372.06128. Found: C, 71.1; H, 4.8;
[M+], 372.06147.
4.3.7.2. Reaction 2. The reaction procedure was the
same as in the general procedure except that the quanti-
ties of reagents were as follows. 4-Ferrocenylphenol
(972 mg, 3.5 mmol), 4-formylbenzeneboronic acid (630
mg, 4.2 mmol), copper(II) acetate (637 mg, 3.6 mmol),
,
Et3N (1.82 g, 1.8 mmol), 4 A molecular sieves (1.5 g)
and CH2Cl2 (140 cm3). The product was obtained as
red crystals (456 mg, 34%), characterized as in Section
4.3.7.1.
4.3.5. 4-(4-Octyloxyphenoxy)phenylferrocene
The reaction yielded the product as orange crystals
(72 mg, 21%), m.p. 75–76 °C; IR (KBr cm−1) 3108,
2924, 2855, 1598, 1502, 1473, 1449, 1386, 1281, 1229,
4.3.8. 4-(4-Bromophenoxy)phenylferrocene
1
1171, 1104, 999, 889, 720, 649, 505; H-NMR (CDCl3)
The reaction yielded the product as yellow crystals
(60 mg, 19%), m.p. 110–111 °C; IR (KBr cm−1) 3099,
2934, 2851, 1579, 1520, 1490, 1449, 1241, 1164, 1105,
7.39 (2H, d, J 8.3, ArH), 6.98 (2H, d, J 8.9, ArH), 6.89
(4H, m, ArH), 4.58 (2H, s, C5H4), 4.28 (2H, s, C5H4),
4.04 (5H, s, C5H5), 3.94 (2H, t, J 6.5, OCH2), 1.78 (2H,
quintet, CH2), 1.55–1.25 (10H, m, CH2×5), 0.88 (3H,
t, CH3); 13C-NMR (CDCl3) 157.23, 155.81, 150.49,
133.66, 127.65, 121.03, 117.95, 115.87, 85.94, 69.96,
69.08, 68.92, 66.73, 32.21, 29.77, 29.74, 29.64, 26.46,
23.06, 14.50; m/z 483 (35), 482 [M+, 100], 480 (7), 426
(8), 371 (9), 370 (36), 369 (4), 277 (2), 262 (3), 261 (16),
185 (3). Anal. Calc. for C30H34FeO2: [M], 482,19082.
Found: [M+], 482.19104.
1
1004, 856, 809, 530, 483; H-NMR (CDCl3) 7.43 (4H,
m, ArH), 6.91 (4H, m, ArH), 4.59 (2H, t, J 1.8, C5H4),
4.30 (2H, t, J 1.8, C5H4), 4.05 (5H, s, C5H5); 13C-NMR
(CDCl3) 157.09, 155.19, 135.25, 133.04, 127.84, 120.64,
119.46, 115.85, 85.39, 69.96, 69.24, 66.77; m/z 435 (25),
434 (95), 433 (26), 432 [M+, 100], 353 (3), 297 (2), 293
(7), 291 (7), 261 (3), 217 (6), 216 (6), 139 (6), 121 (11).
Anal. Calc. for C22H17BrFeO: C, 61.2; H, 4.0; [M],
431.98122. Found: C, 61.7; H, 4.4%; [M+], 431.97884.
4.3.6. 4-(4-Benzyloxyphenoxy)phenylferrocene
4.3.9. 4-(4-Trifluoromethylphenoxy)phenylferrocene
The reaction yielded the product as red crystals (7
mg, 2%), m.p. 106–107 °C; IR (KBr cm−1) 3074, 2926,
2849, 1614, 1523, 1510, 1455, 1416, 1324, 1253, 1159,
1116, 1107, 1066, 1033, 888, 853, 838, 817, 625, 588,
The reaction yielded the product as orange crystals
(148 mg, 44%), m.p. 157–158 °C; IR (KBr cm−1
)
2930, 2864, 1507, 1460, 1381, 1235, 1108, 1019, 888,
1
860, 818, 752, 710, 644, 527, 494; H-NMR (CDCl3)
1
7.37 (7H, m, ArH), 6.98 (4H, m, ArH), 6.88 (2H, d, J
8.5, ArH), 5.06 (2H, s, CH2), 4.65 (2H, s, C5H4), 4.28
(2H, s, C5H4), 4.05 (5H, s, C5H5); 13C-NMR (CDCl3)
157.00, 155.38, 150.99, 137.41, 133.84, 129.00, 128.40,
127.90, 127.66, 120.95, 118.14, 116.30, 85.80, 70.95,
69.91, 69.06, 66.68; m/z 462 (9), 461 (39), 460 [M+,
100], 458 (7), 370 (15), 369 (47), 262 (11), 261 (56),
260 (8), 205 (10), 203 (6), 139 (5), 121 (6). Anal. Calc.
for C29H24FeO2: [M], 460.11257. Found: [M+],
460.11256.
528, 490; H-NMR (CDCl3) 7.58 (2H, d, J 8.5, ArH),
7.48 (2H, d, J 8.5, ArH), 7.07 (2H, d, J 8.6, ArH), 6.98
(2H, d, J 8.5, ArH), 4.62 (2H, t, J 1.8, C5H4), 4.33 (2H,
t, J 1.8, C5H4), 4.07 (5H, s, C5H5); 13C-NMR (CDCl3)
161.02, 154.15, 136.13, 127.96, 127.52, 127.47, 120.33,
118.08, 85.17, 69.99, 69.35, 66.82; m/z 424 (4), 423 (27),
422 [M+, 100], 420 (7), 283 (2), 282 (12), 211 (4), 140
(15), 139 (18), 126 (6), 121 (4). Anal. Calc. for
C23H17F3FeO: [M], 422.05809. Found: [M+],
422.05925.

78
C. Imrie et al. / Journal of Organometallic Chemistry 645 (2002) 65–81
4.3.10. 4-(3-Fluorophenoxy)phenylferrocene
386 (3), 363 (4), 278 (3), 261 (4), 222 (3), 185 (4), 121
(4). Anal. Calc. for C25H24FeO4: C, 67.6; H, 5.4; [M],
444.10240. Found: C, 67.9; H, 5.9%; [M+], 444.10201.
The reaction yielded the product as yellow crystals
(73 mg, 27%), m.p. 87–89 °C; IR (KBr cm−1) 3071,
3025, 2923, 1595, 1522, 1490, 1444, 1264, 1223, 1103,
1
4.3.14. 4-(3-Nitrophenoxy)phenylferrocene
961, 841, 685; H-NMR (CDCl3) 7.46 (2H, d, J 8.6,
The reaction procedure was the same as in the gen-
eral procedure except that the reagents were used in the
following quantities: 4-ferrocenylphenol (1.0 g, 3.60
mmol), 3-nitrobenzeneboronic acid (516 mg, 3.094
mmol), copper(II) acetate (650 mg, 3.6 mmol), Et3N
ArH), 7.25 (1H, m, ArH), 6.97 (2H, d, J 8.6, ArH), 6.76
(3H, m, ArH), 4.61 (2H, t, J 1.7, C5H4), 4.31 (2H, t, J
1.7, C5H4), 4.06 (5H, s, C5H5); 13C-NMR (CDCl3)
154.73, 130.90, 130.77, 127.85, 119.93, 114.17, 110.22,
109.94, 106.38, 106.06, 85.36, 69.97, 69.25, 66.79; m/z
373 (26), 372 [M+, 100], 370 (7), 277 (2), 261 (3), 186
(5), 121 (10). Anal. Calc. for C22H17FFeO: C, 71.0; H,
4.6; [M], 372.06128. Found: C, 71.3; H, 4.8%; [M+],
372.06200.
,
(1.82 g, 18 mmol), 4 A molecular sieves (1.5 g) and
CH2Cl2 (150 cm3). The reaction yielded the product as
red crystals (145 mg, 10%), m.p. 92–94 °C; IR (KBr
cm−1) 3097, 2920, 2849, 1618, 1524, 1471, 1449, 1347,
1276, 1236, 1107, 942, 884, 858, 844, 818, 742, 667, 520;
1H-NMR (CDCl3) 7.93 (1H, dd, J 7.8, 1.2, ArH), 7.82
(1H, t, J 2.2, ArH), 7.49 (3H, m, ArH), 7.33 (1H, dd, J
8.2, 2.4, ArH), 6.98 (2H, d, J 8.7, ArH), 4.68 (2H, t, J
1.8, C5H4), 4.32 (2H, t, J 1.8, C5H4), 4.07 (5H, s, C5H5);
13C-NMR (CDCl3) 159.05, 153.94, 149.70, 136.56,
130.69, 128.15, 124.39, 120.19, 117.92, 113.12, 85.06,
70.02, 69.40, 66.88; m/z 401 (4), 400 (26), 399 [M+,
100], 397 (10), 353 (8), 352 (4), 277 (3), 260 (3), 199 (3),
139 (4), 121 (13). Anal. Calc. for C22H17FeNO3: C,
66.2; H, 4.3; N, 3.5; [M], 399.05578. Found: C, 66.3; H,
4.5; N, 3.4%; [M+], 399.05582.
4.3.11. 4-(4-Trifluoromethoxyphenoxy)phenylferrocene
The reaction yielded the products as yellow crystals
(89 mg, 28%), m.p. 74–76 °C; IR (KBr cm−1) 3088,
2920, 2849, 1520, 1502, 1453, 1276, 1244, 1187, 1169,
1
1107, 893, 858, 818, 529; H-NMR (CDCl3) 7.45 (2H,
d, J 8.7, ArH), 7.21 (2H, d, J 8.4, ArH), 7.01 (2H, d, J
9.1, ArH), 6.94 (2H, d, J 8.7, ArH), 4.59 (2H, t, J 1.8,
C5H4), 4.30 (2H, t, J 1.8, C5H4), 4.05 (5H, s, C5H5);
13C-NMR (CDCl3) 156.43, 155.22, 144.72, 135.36,
127.87, 122.97, 122.61, 119.72, 119.55, 119.22, 85.41,
69.99, 69.28, 66.79; m/z 439 (36), 438 [M+, 100%], 436
(7), 261 (2), 232 (2), 219 (8), 139 (3), 121 (5). Anal.
Calc. for C23H17F3FeO2: C, 63.1; H, 3.9; [M],
438.05300. Found: C, 63.3; H, 3.9%; [M], 438.05330.
4.4. Preparation of arylferrocenylphenyl amines. The
reaction of 4-ferrocenylaniline and 4-substituted
phenylboronic acids
To a 100 cm3 RB flask was added 4-ferrocenylaniline
(200 mg, 0.72 mmol), copper(II) acetate (131 mg, 0.72
mmol), the 4-substituted phenylboronic acid (0.86
4.3.12. 4-(4-Acetylphenoxy)phenylferrocene
The reaction yielded the product as orange crystals
(92 mg, 32%), m.p. 118–120 °C; IR (KBr cm−1) 3097,
2920, 1674, 1594, 1526, 1503, 1451, 1354, 1269, 1166,
,
mmol) and powdered 4 A molecular sieves (300 mg).
1
To this mixture was added anhydrous CH2Cl2 (20 cm3)
and Et3N (364 mg, 3.60 mmol). The reaction mixture
was allowed to stir at r.t. for 168 h. The reaction
mixture was then filtered through a column of silica gel
and Et2O was used to strip the column of the organic
components. The solvent was removed in vacuo and the
residue was then subjected to separation and purifica-
tion by preparative thin layer plate chromatography.
The developing solvent used was either C6H14–CH2Cl2
(50/50) (for the methyl derivative) or a solvent system
consisting of C6H14–CH2Cl2–ether (60/35/5) (for the
methoxy and bromo derivatives). Considerable quanti-
ties of dark inorganic materials were removed from the
reaction mixtures during the purification steps.
1109, 829, 594, 531, 497; H-NMR (CDCl3) 7.95 (2H,
d, J 8.8 ArH), 7.48 (2H, d, J 8.5, ArH), 7.01 (4H, t, J
8.8, ArH), 4.64 (2H, t, J 1.8, C5H4), 4.34 (2H, t, J 1.8,
C5H4) 4.08 (5H, s, C5H5), 2.58 (3H, s, CH3); 13C-NMR
(CDCl3) 197.11, 162.48, 153.95, 136.25, 132.23, 130.99,
127.95, 120.52, 117.54, 70.12, 69.47, 66.90, 26.84; m/z
397 (31), 396 [M+, 100], 394 (7), 353 (5), 261 (2), 191
(3), 190 (11), 121 (8). Anal. Calc. for C24H20FeO2: C,
72.8; H, 5.1; [M], 396.08127. Found: C, 72.5; H, 5.3%;
[M], 396.08036.
4.3.13. 4-(3,4,5-Trimethoxyphenoxy)phenylferrocene
The reaction yielded the product as orange crystals
(112 mg, 42%), m.p. 131–133 °C; IR (KBr cm−1
)
3084, 2957, 2927, 2830, 1606, 1504, 1467, 1425, 1413,
1
1226, 1184, 1130, 991, 816, 490; H-NMR (CDCl3) 7.44
4.4.1. 4-(4-Methylanilino)phenylferrocene
(2H, d, J 8.7, ArH), 6.93 (2H, d, J 8.4, ArH), 6.21 (2H,
s, ArH), 4.60 (2H, s, C5H4), 4.30 (2H, s, C5H4), 4.05
(5H, s, C5H5), 3.82 (9H, s, 3× OCH3); 13C-NMR
(CDCl3) 155.74, 153.89, 153.26, 134.14, 134.06, 127.32,
118.27, 96.78, 85.53, 69.76, 68.97, 66.41, 61.03, 56.13;
m/z 446 (5), 445 (29), 444 [M+, 100], 442 (6), 414 (3),
The reaction yielded the product as a yellow solid (38
mg, 14%), m.p., 118–120 °C; IR (KBr cm−1) 3396
(NH), 3098, 2964, 2925, 1615, 1536, 1520, 1456, 1330,
1183, 1104, 1084, 1027, 1003, 888, 820, 498; H-NMR
(CDCl3) 7.35 (2H, d, J 8.5, ArH), 7.09 (2H, d, J 8.3,
ArH), 7.00 (2H, d, J 8.4, ArH), 6.95 (2H, d, J 8.5,
l

C. Imrie et al. / Journal of Organometallic Chemistry 645 (2002) 65–81
79
ArH), 5.59 (1H, s[br], NH), 4.56 (2H, t, J 1.5, C5H4),
4.25 (2H, t, J 1.5, C5H4), 4.04 (5H, s, C5H5), 2.30 (3H,
s, CH3); 13C-NMR (CDCl3) 142.34, 140.87, 131.39,
131.07, 130.28, 127.48, 118.99, 117.51, 86.57, 69.88,
68.84, 66.39, 21.12; m/z 369 (3), 368 (20), 367 [M,+
100], 366 (3), 246 (7), 184 (7), 121 (3). Anal. Calc. for
C23H21FeN: [M], 367.10234. Found: [M+], 367.10201.
ArH), 4.70 (2H, t, J 1.8, C5H4), 4.36 (2H, t, J 1.8,
C5H4), 4.08 (5H, s, C5H5), 3.09 (2H, t, J 6.6, OCH2),
1.81 (2H, m, CH2), 1.57–1.44 (4H, m, 2×CH2), 0.95
(3H, m, CH3) m/z 529 (39%), 527 [M+, 100], 525 (9),
457 (8), 456 (11), 228 (12). Anal. Calc. for
C34H33FeNO: C, 77.4; H, 6.3; N, 2.7; [M], 527.19115.
Found: C, 77.0; H, 6.6; N, 2.6%; [M+], 527.19210.
4.4.2. 4-(4-Methoxyanilino)phenylferrocene
4.5.2. 4-Octyloxy-N-[4-(4-ferrocenylphenyl)-
The reaction yielded the product as a brown solid (9
mg, 3%), m.p., 144–147 °C; IR (KBr cm−1) 3392
(NH), 3105, 2964, 2930, 2856, 1614, 1533, 1520, 1460,
benzylidene]aniline
Quantities: 4%-formyl-4-biphenylferrocene (150 mg,
0.41 mmol) and 4-octyloxyaniline (91 mg, 0.41 mmol).
The experimental procedure was as described for 4-
pentyloxy-N-[4-(4-ferrocenylphenyl)benzylidene]aniline.
The product was isolated as a yellow solid (170 mg,
73%), m.p. (liquid crystal) 177 °C (K/S), 183 °C (S/N),
201 °C (N/I); IR (KBr cm−1) 3112, 3097, 3048, 2968,
2870, 1627, 1610, 1578, 1514, 1481, 1400, 1303, 1270,
1197, 1116, 1043, 1010, 897, 840, 735; 1H-NMR
(CDCl3) 8.53 (1H, s, CH), 7.97 (2H, d, J 8.3, ArH),
7.73 (2H, d, J 8.3, ArH), 7.58 (4H, m, ArH), 7.26 (2H,
d, J 8.8, ArH), 6.94 (2H, d, J 8.8, ArH), 4.70 (2H, t, J
1.8, C5H4), 4.36 (2H, t, J 1.8, C5H4), 4.08 (5H, s, C5H5),
3.99 (2H, t, J 6.6, OCH2), 1.80 (2H, m, CH2), 1.56–1.30
(10H, m, 5×CH2), 0.90 (3H, m, CH3); 13C-NMR
(CDCl3) 158.30, 158.23, 145.15, 143.77, 139.64, 137.99,
135.63, 129.50, 127.43, 127.37, 126.95, 122.63, 115.39,
85.08, 70.10, 69.57, 68.70, 66.96, 32.25, 29.81, 29.74,
29.68, 26.49, 23.10, 14.55; m/z 570 (43%), 569 [M+,
100], 567 (7), 457 (9), 456 (10), 228 (10). Anal. Calc. for
C37H39FeNO: C, 78.0; H, 6.9; N, 2.5; [M], 569.23810.
Found: C, 78.1; H, 7.2; N, 2.4%; [M+], 569.23754.
l
1328, 1301, 1254, 1104, 1031, 831, 811, 566, 503; H-
NMR (CDCl3) 7.34 (2H, d, J 8.6, ArH), 7.08 (2H, d, J
8.9, ArH), 6.87 (2H, d, J 9.0, ArH), 6.86 (2H, d, J 8.7,
ArH), 5.49 (1H, s[br], NH), 4.55 (2H, t, J 1.8, C5H4),
4.25 (2H, t, J 1.8, C5H4), 4.04 (5H, s, C5H5), 3.81 (3H,
s, OCH3); 13C-NMR (CDCl3) 155.11, 143.19, 135.93,
130.20, 127.11, 121.81, 115.87, 114.69, 86.31, 69.43,
68.33, 65.91, 55.61; m/z 385 (4), 384 (27), 383 [M,+
100], 368 (9), 261 (7), 191 (4), 184 (5), 121 (4). Anal.
Calc. for C23H21FeNO: [M], 383.09725. Found: [M+],
383.09706.
4.4.3. 4-(4-Bromoanilino)phenylferrocene
The reaction yielded the product as a yellow solid (87
mg, 28%), m.p., 118–120 °C; IR (KBr cm−1) 3400
(NH), 3088, 2960, 2922, 2853, 2360, 1594, 1529, 1498,
1454, 1384, 1324, 1261, 1174, 1104, 1074, 1031, 1000,
l
888, 819, 518; H-NMR (CDCl3) 7.39 (2H, d, J 8.6,
ArH), 7.35 (2H, d, J 8.8, ArH), 7.00 (2H, d, J 8.6,
ArH), 6.94 (2H, d, J 8.8, ArH), 5.67 (1H, s[br], NH),
4.58 (2H, t, J 1.8, C5H4), 4.28 (2H, t, J 1.8, C5H4), 4.05
(5H, s, C5H5); m/z 434 (26), 433 [M,+ 100], 432 (25),
431 (93), 368 (5), 366 (5), 297 (5), 296 (20), 231 (10), 229
(4), 228 (5), 216 (8), 139 (5), 121 (4). Anal. Calc. for
C22H18FeN79Br: [M], 430.99720. Found: [M+],
430.99710.
4.5.3. 4-Tetradecyloxy-N-[4-(4-ferrocenylphenyl)-
benzylidene]aniline
Quantities: 4%-formyl-4-biphenylferrocene (150 mg,
0.41 mmol) and 4-tetradecyloxyaniline (125 mg, 0.41
mmol). The experimental procedure was as described
for 4-pentyloxy-N-[4-(4-ferrocenylphenyl)benzylidene]-
aniline. The product was isolated as a yellow solid (214
mg, 75%), m.p. (liquid crystal) 146 °C (K/S), 164 °C
(S/N), 182 °C (N/I); IR (KBr cm−1) 3113, 3080, 3048,
2935, 2871, 1910, 1886, 1773, 1627, 1603, 1578, 1513,
1473, 1400, 1303, 1254, 1197, 1157, 1116, 1027, 1010,
4.5. Preparation of elongated ferrocenes
4.5.1. 4-Pentyloxy-N-[4-(4-ferrocenylphenyl)-
benzylidene]aniline
To a solution containing 4%-formyl-4-biphenylfer-
rocene (150 mg, 0.41 mmol) and 4-pentyloxyaniline (73
mg, 0.41 mmol) in anhydrous MeOH (30 cm3) was
1
897, 840, 824, 735; H-NMR (CDCl3) 8.63 (1H, s, CH),
7.96 (2H, d, J 8.3, ArH), 7.73 (2H, d, J 8.2, ArH), 7.58
(4H, m, ArH), 7.26 (2H, d, J 8.7, ArH), 6.94 (2H, d, J
8.7, ArH), 4.70 (2H, t, J 1.7, C5H4), 4.36 (2H, t, J 1.7,
C5H4), 4.07 (5H, s, C5H5), 3.98 (2H, t, J 6.6, OCH2),
1.80 (2H, m, CH2), 1.47–1.27 (22H, m, 11×CH2), 0.88
(3H, m, CH3); 13C-NMR (CDCl3) 157.94, 157.81,
143.41, 139.27, 137.63, 135.25, 129.12, 127.04, 126.98,
126.56, 122.23, 115.04, 84.72, 69.70, 69.17, 68.35, 66.57,
31.95, 29.69, 29.63, 29.45, 29.39, 26.09, 22.72, 14.15;
m/z 654 (50%), 653 [M+, 100], 652 (6), 651 (8), 457 (9),
456 (10), 228 (10). Anal Calc. for C43H51FeNO: C, 79.0;
,
added 4 A molecular sieves (0.40 g), and the mixture
was heated under reflux overnight. The reaction mix-
ture was then concentrated in vacuo, and the residue
recrystallized from CH2Cl2–C6H14 in the cold (213 mg,
99%), m.p. 210–212 °C; IR (KBr cm−1) 3112, 3080,
3048, 2952, 2871, 1919, 1627, 1610, 1505, 1481, 1392,
1295, 1254, 1197, 1181, 1116, 1091, 1059, 1035, 1019,
l
995, 897, 832; H-NMR (CDCl3) 8.53 (1H, s, CH), 7.97
(2H, d, J 8.3, ArH), 7.73 (2H, d, J 8.3, ArH), 7.58 (4H,
m, ArH), 7.26 (2H, d, J 8.7, ArH), 6.94 (2H, d, J 8.9,

80
C. Imrie et al. / Journal of Organometallic Chemistry 645 (2002) 65–81
H, 7.9; N, 2.1; [M], 653.33200. Found: C, 79.0; H, 8.2;
N, 2.1%; [M+], 653.33108.
277 (12), 262 (15), 261 (23), 203 (6). Anal. Calc. for
C43H51FeNO2: C, 77.2; H, 7.7; N, 2.1; [M], 669.32692.
Found: C, 77.0; H, 8.5; N, 2.0%; [M+], 669.32537.
4.5.4. 4-Pentyloxy-N-{1-[4( ferrocenylphenoxy)-
phenyl]methylidene}aniline
To a solution containing 4-(4-formylpenoxy)phenyl-
ferrocene (200 mg, 0.52 mmol) and 4-pentyloxyaniline
(93 mg, 0.52 mmol) in anhydrous MeOH (30 cm3) was
4.6. Larger scale reaction for GC–MS analysis.
4-(4-Methylphenoxy)phenylferrocene
The reaction was repeated as in the general proce-
dure except that the quantities of the reactants and
reagents were scaled up. The quantities were as follows:
4-Ferrocenylphenol (1.00 g, 3.6 mmol), 4-methylben-
zeneboronic acid (585 mg, 4.3 mmol), copper(II) ace-
,
added 4 A molecular sieves (400 mg) and the mixture
was heated under reflux overnight. The reaction mix-
ture was then concentrated in vacuo and the residue
recrystallized from CH2Cl2–MeOH in the cold (148
mg, 52%), m.p. 151–153 °C; IR (KBr cm−1) 2949,
1601, 1503, 1451, 1249, 1160, 1104, 897, 832, 531;
1H-NMR (CDCl3) 8.44 (1H, s, CH), 7.86 (2H, d, J 8.7,
ArH), 7.47 (2H, d, J 8.6, ArH), 7.21 (2H, d, J 8.8,
ArH), 7.08 (2H, d, J 8.7, ArH), 7.00 (2H, d, J 8.6,
ArH), 6.92 (2H, d, J 8.8, ArH), 4.61 (2H, t, J 1.8,
C5H4), 4.31 (2H, t, J 1.8, C5H4), 4.07 (5H, s, C5H5),
3.97 (2H, t, J 6.6, OCH2), 1.80 (2H, m, CH2), 1.53–1.33
(4H, m, 2×CH2), 0.94 (3H, t, CH3); 13C-NMR
(CDCl3) 160.54, 158.14, 157.73, 154.72, 135.58, 131.79,
130.65, 127.86, 122.49, 120.05, 118.57, 115.38, 85.36,
69.97, 69.27, 68.68, 66.79, 29.40, 28.61, 22.87, 14.42;
m/z 545 (9), 544 (39), 543 [M+, 100], 541 (7), 473 (5),
472 (4), 408 (3), 407 (10), 379 (3), 237 (3), 236 (9), 121
(3). Anal. Calc. for C34H33FeNO2: C, 75.2; H, 6.1; N,
2.6; [M], 543.18607. Found: C, 75.0; H, 6.8; N, 2.4%;
[M+], 543.18565.
,
tate (655 mg, 3.6 mmol), Et3N (1.82 g, 18 mmol), 4 A
molecular sieves (1.5 g) and CH2Cl2 (100 cm3). The
reaction was analyzed by GC–MS. The following com-
pounds were identified as major components; 4-
(4-methylphenoxy)phenylferrocene and 4-ferrocenyl-
phenol. Minor components were p-cresol, 4,4%-
dimethylbiphenyl, 4,4%-dimethylbiphenyl ether and 4-
acetoxytoluene.
4.7. Crystal structure determination
Crystal data for 6: Mr=322.19 g mol−1, size 0.25×
0.24×0.08 mm, orthorhombic, space group Pbca,
,
a=9.8870(11), b=10.7315(12), c=31.933(3) A, V=
3
3388.2 (6) A , T=296 K, Z=8, zcalc=1.436 g cm−3
,
,
m(Mo–Ka)=0.897 mm−1, F(000)=1520, 35755 reflec-
tions in h(−13/13), k(−14/14), l(−42/38), measured
in the range 5.655[525.00°, 4180 independent reflec-
tions,
1obs=0.0466, wR2obs=0.1167, R1all=0.1286, wR2all
0.1600, goodness-of-fit=0.822, largest difference peak
Rint=0.1206, 230 parameters, 0 restraints.
4.5.5. 4-Tetradecyloxy-N-{1-[4-( ferrocenylphenoxy)-
phenyl]methylidene}aniline
R
=
To
a
solution containing 4-(4-formylphenoxy)-
−3
,
and hole: 0.213/−0.429 e A
.
phenylferrocene (200 mg, 0.52 mmol) and 4-tetradecy-
cloxyaniline (159 mg, 0.52 mmol) in anhydrous MeOH
3
,
(30 cm ) was added 4 A molecular sieves (400 mg) and
5. Supplementary material
the mixture was heated under reflux overnight. The
reaction mixture was then concentrated in vacuo and
the residue recrystallized from CH2Cl2–MeOH in the
Crystallographic data for the structural analysis have
been deposited with the Cambridge Crystallographic
Data Centre, CCDC no. 157093 for compound 4.
Copies of this information may be obtained free of
charge from The Director, CCDC, 12 Union Road,
Cambridge CB2 1EZ, UK (Fax: +44-1223-336033;
e-mail: deposit@ccdc.cam.ac.uk or www: http://
www.ccdc.cam.ac.uk).
cold (151 mg, 43%), m.p. 126–128 °C; IR (KBr cm−1
)
3073, 2920, 2849, 1596, 1502, 1461, 1279, 1250, 1156,
1
1103, 1020, 885, 838, 721, 544, 521; H-NMR (CDCl3)
8.44 (1H, s, CH), 7.86 (2H, d, J 8.7, ArH), 7.47 (2H, d,
J 8.6, ArH), 7.21 (2H, d, J 8.8, ArH), 7.08 (2H, d, J 8.6,
ArH), 6.99 (2H, d, J 8.6, ArH), 6.92 (2H, d, J 8.8,
ArH), 4.61 (2H, t, J 1.7, C5H4), 4.31 (2H, t, J 1.7,
C5H4), 4.06 (5H, s, C5H5), 3.97 (2H, t, J 6.5, OCH2),
1.79 (2H, m, CH2), 1.60–1.26 (22H, m, 11×CH2), 0.88
(3H, t, CH3); 13C-NMR (CDCl3) 160.54, 158.16,
157.69, 154.74, 145.21, 135.58, 131.81, 130.64, 127.86,
122.48, 120.04, 118.57, 115.40, 85.37, 69.97, 69.26,
68.72, 66.79, 32.31, 30.05, 29.99, 29.80, 29.74, 29.71,
26.45, 23.07, 14.50; m/z 672 (8), 671 (32), 670 (83), 669
[M+, 100], 668 (23) 667 (18), 487 (5), 486 (7), 485 (8),
474 (11), 473 (16), 472 (12), 408 (12), 407 (14), 380 (9),
379 (15), 367 (11), 354 (9), 353 (13), 305 (10), 278 (26),
Acknowledgements
The authors wish to thank the following persons for
technical assistance: Mr H. Marchard (UPE) for gen-
eral technical assistance, Dr P. Boshoff (Cape Tech-
nikon, Cape Town) for his mass spectroscopic analyses,
Dr R. Sheets (Rhodes University, Grahamstown) for
help with use of the Linkam hotstage and polarizing
microscope and Dr B. Schoonees (Port Elizabeth Tech-

C. Imrie et al. / Journal of Organometallic Chemistry 645 (2002) 65–81
81
(i) T. Seshadri, H.-J. Haupt, Chem. Commun. (1998) 735.
nikon) for help with GC–MS analyses. The National
Research Foundation and the University of Port Eliza-
beth are thanked for funding. The authors wish to
extend a special word of gratitude to Lancaster Synthe-
sis (UK) for the supply of phenylboronic acids.
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