Synthesis of N-tetrasubstituted cyclam derivatives appended with sulfonyl or sulfinyl groups via aza-Michael addition

Article abstract of DOI:10.1016/j.tet.2007.07.067

Azamacrocycles bearing four arylsulfonyl or arylsulfinyl pendant arms have been synthesised with good yields through nucleophilic addition of 1,4,8,11-tetraazacyclotetradecane (cyclam) to phenylvinylsulfone, phenylvinylsulfoxide or (R)-tolylvinylsulfoxide

Full text of DOI:10.1016/j.tet.2007.07.067

Tetrahedron 63 (2007) 10330–10336
Synthesis of N-tetrasubstituted cyclam derivatives appended
with sulfonyl or sulfinyl groups via aza-Michael addition
Augustin de Castries, Aude Escande, H ꢀe l ꢁe ne Fensterbank, Emmanuel Magnier,
J ꢀe r oˆ me Marrot and Chantal Larpent
*
Institut Lavoisier, CNRS UMR 8180, Universite´ de Versailles Saint-Quentin, 45 avenue des Etats-Unis, 78035 Versailles Cedex, France
Received 21 June 2007; revised 16 July 2007; accepted 18 July 2007
Available online 26 July 2007
Abstract—Azamacrocycles bearing four arylsulfonyl or arylsulfinyl pendant arms have been synthesised with good yields through nucleo-
philic addition of 1,4,8,11-tetraazacyclotetradecane (cyclam) to phenylvinylsulfone, phenylvinylsulfoxide or (R)-tolylvinylsulfoxide in iso-
propanol/water media. The crystal structure of the tetraethylsulfonylphenyl substituted macrocycle has been determined by X-ray
crystallography. Preliminary studies of the coordination properties of these functionalised macrocyles towards Cu(II) and Eu(III) indicate
that pendant sulfoxide groups act as oxygen donor coordinating groups.
Ó 2007 Elsevier Ltd. All rights reserved.
1. Introduction
studied and used to obtain a variety of appended cyclam
derivatives.
1
7,19–22
Macrocyclic ligands and in particular polyazamacrocycles
have received a great deal of research interest since they
find various applications in numerous fields such as coordi-
nation chemistry, biomedical uses, ion sequestration and
Vinyl- and alkenylsulfones and sulfoxides are excellent
Michael acceptors and have been found to react with a num-
ber of nucleophiles. Among them vinyl- and divinylsul-
fones have been the most widely studied and aza-Michael
2
3–35
1
–7
extraction or catalysis. Among them, cyclam (1,4,8,11-
tetraazacyclotetradecane) has attracted a widespread atten-
tion owing to its high affinity for transition metals.
additions to vinylsulfones have proven to be useful synthetic
as
1
–6,8
15,24–32
tools for the functionalisation of various amines
3
3
Numerous cyclam derivatives have been reported and the
presence of additional functionalities on one or several pen-
dant arms has been found to enlarge the recognition and
well as in the synthesis of nitrogen heterocycles. Except
for the reaction of cyclam with divinylsulfone, that has
been found to lead to a 1,8-N,N-bisethylsulfonyl bridged
1
–6,9–14
30
15
complexation properties.
The grafting of pendant
macrocycle, and with perfluorinated acceptors, the
synthesis of cyclam derivatives with appended sulfinyl or
sulfonyl groups, through aza-Michael additions, has never
been investigated before. We anticipated that conjugate ad-
ditions of cyclam to vinylsulfones or sulfoxides would
give a straightforward access to new families of N-ethylsul-
finyl and N-ethylsulfonyl substituted macrocycles. Such
functionalised cyclam derivatives may present interesting
binding properties since the appended SO groups may act
as auxiliary ligands in the formation of coordination
complexes. Furthermore, reaction with enantiomerically
pure vinylsulfoxides could give access to optically active
ligands or organocatalysts usable in asymmetric catalysis.
Moreover, electrophilic substitutions in the alpha-position
to the sulfonyl groups, well known and widely used in the
arms has also been used to modulate the solubility as well
as the solution behaviour: cyclam derivatives with appended
perfluorinated tails have been used as ligands in fluorous bi-
1
5,16
phasic catalysis, macrocyclic surfactants have been de-
signed by linking amphiphilic groups onto the cyclam.
1
7,18
Functionalisation of cyclam is usually performed by
N-alkylation of its secondary amines via nucleophilic substi-
tution with halogenated or tosylated reagents. Alternatively,
some cyclam derivatives have been obtained through nucle-
1
3,15,17,19–22
ophilic additions of cyclam to Michael acceptors:
among them reactions with acrylic derivatives (like acryloni-
trile, acrylic esters or acrylamides) have been the most widely
2
5
chemistry of b-aminosulfones, might permit further func-
tionalisations.
Keywords: Azamacrocycles; Vinylsulfone; Vinylsulfoxide; Coordination
complexes.
Herein, we describe the straightforward synthesis of N-tetra-
substituted cyclam derivatives with ethylarylsulfonyl and
*
Corresponding author. Tel.: +33 139254413; fax: +33 139254452; e-mail:
larpent@chimie.uvsq.fr
0
040–4020/$ - see front matter Ó 2007 Elsevier Ltd. All rights reserved.
doi:10.1016/j.tet.2007.07.067

A. de Castries et al. / Tetrahedron 63 (2007) 10330–10336
10331
ethylarylsulfinyl pendant arms, via aza-Michael additions as
well as preliminary studies of their coordination properties
towards Cu(II) and Eu(III).
Table 1. Reaction conditions for the synthesis of sulfinyl and sulfonyl ap-
pended macrocycles 4–6
ꢀ
Entry Michael
acceptor
Solvent
T/
C Reaction Product Yield/%
time
a
2 (5 equiv) i-PrOH
b
1
2
3
4
5
6
7
8
rt
2 (5 equiv) i-PrOH/H O (2/1) rt
3 days
24 h
5 days
4
4
4
4
5
5
6
6
16
56
55
75
69
13
68
82
a
b
2
. Results and discussion
2
a
2 (5 equiv) i-PrOH/H
b
2
2
2
2
2
O (2/1) rt
a
2 (5 equiv) i-PrOH/H
b
O (2/1) 65 24 h
O (2/1) 65 15 h
2.1. Synthesis of the N-tetrasubstituted macrocycles
appended with sulfinyl and sulfonyl groups
a
3 (5 equiv) i-PrOH/H
b,d
b,d
c
a
3 (5 equiv) i-PrOH/H
O (2/1) rt
O (2/1) rt
15 h
17 h
7 h
a
1 (6 equiv) i-PrOH/H
a
c
The synthesis of tetrasubstituted macrocycles was investi-
gated via nucleophilic addition of cyclam to phenyl vinyl
sulfone 1, phenyl vinyl sulfoxide 2 as well as to the enantio-
merically pure (R)-p-tolyl vinyl sulfoxide 3 (Scheme 1). The
latter has been prepared via the nucleophilic substitution of
vinyl magnesium bromide on (S) menthyl-p-toluenesulfinate
1 (10 equiv) i-PrOH/H O (2/1) rt
2
a
b
c
d
Number of equivalent per cyclam.
Isolated yield after purification by column chromatography.
Isolated yield after recrystallisation.
The optical rotation is identical for the products obtained at 65 C or at rt.
ꢀ
3
6
following Kagan’s experimental conditions.
ꢀ
and best conversions were obtained at 65 C. The tetrasub-
stituted macrocycles 4 and 5 have been isolated after purifi-
cation by column chromatography in 70–75% yields from 2
and 3 (Table 1, entries 4,5). These experimental conditions
within this range of temperatures do not induce racemisation
of the sulfinyl groups since the optical activity of the macro-
cycle 5 is the same as when the reaction was run at room
temperature (Table 1, entries 5,6). The tetrasubstituted mac-
rocycles 4 and 5 have been fully characterised. Elemental
analyses and mass spectra confirmed the grafting of four
arylethylsulfinyl pendant arms. The observed number of
The reactions were performed with an excess of Michael
acceptors in protic solvents. The different sets of experimen-
tal conditions tested are summarised in Table 1.
The choice of the solvent i-PrOH or i-PrOH/water was made
according to published results that demonstrated that hetero-
Michael additions are favoured in protic medium with re-
markable rate accelerations in water presumably due to
a faster proton transfer.
nyl and sulfonyl substituted acceptors, addition of amines to
vinylsulfoxide and vinylsulfone derivatives was found to be
faster in ethanol than in benzene
tylamine with a bis-vinylsulfone acceptor proceeded in
methanol but did not occur in chloroform. In the formation
of bridged macrocycles involving aza-Michael additions to
divinylsulfone, best results were obtained in protic media
1
7,37
For instance in the case of sulfi-
1
13
H and C NMR signals and the relative integration of the
corresponding H signals are in agreement with the tetrasub-
stitution pattern.
2
8,34
1
and reaction of isobu-
3
1
The tetrasubstituted macrocycle 6 with sulfonyl pendant
arms was obtained similarly from phenyl vinyl sulfone 1
(Table 1, entries 7,8). The reaction went to completion at
room temperature provided that an excess of Michael accep-
tor (6–10 equiv per cyclam) was used. Room temperature re-
action of cyclam with phenyl vinyl sulfone 1 proceeds more
rapidly than with aryl vinyl sulfoxides 2 and 3, in agreement
with the known higher reactivity of a double bond activated
with a sulfone compared to that substituted with a sulfox-
3
0
(
isopropanol or isopropanol/water).
Furthermore, we
recently found that addition of the amines of cyclam to per-
fluorinated Michael acceptors is readily achieved in an
i-PrOH/water medium.
1
5
In the present case, the reaction of cyclam with a slight ex-
cess of phenyl vinyl sulfoxide 2 (5 equiv per cyclam) pro-
ceeded sluggishly in isopropanol and the reaction rate
significantly increased in isopropanol/water (Table 1, entries
2
4–26
ide. The macrocycle 6 conveniently precipitated out
of the reaction mixture and was crystallised by slow diffu-
sion of methanol through a chloroform solution of 6 in
1
–3). Heating up the reaction mixture improved the yield
O
O
O
O
O
S
O
S
O
S
O
O
H
H
H
H
S
S
S
S
1
2 (rac)
Ph
Ph
N
N
N
N
Ph
S
N
N
N
N
Ph
Ph
N
N
N
N
Ph
Ph
Ph
Ph
i-PrOH / H2O
r.t., 7 h
i-PrOH / H2O
reflux, 24 h
Ph
S
S
O
O
O
O
O
O
6
(82%)
4
(75%)
O
S
O
S
O
3
(R)
S
Ph
Ph
N
N
N
N
Ph
Ph
Tol
i-PrOH / H2O
reflux, 24 h
S
S
O
O
5
(69%)
Scheme 1. Synthesis of sulfinyl and sulfonyl appended macrocycles 4–6.

10332
A. de Castries et al. / Tetrahedron 63 (2007) 10330–10336
Table 2. UV–vis data of Cu(II) complexes with sulfinyl and sulfonyl
appended macrocycles 4–6 and tetra-N-methylcyclam (TMC)
Complex
Colour
Solvent
l/nm
ꢁ1
3/L mol cm )
ꢁ
1
(
TMC$Cu(II)
TMC$Cu(II)
Blue
Blue
Blue
Green
Green
MeOH
EtOH
MeOH
EtOH
EtOH
645 (161)
664 (287)
659 (244)
731 (316)
738 (297)
6
4
5
$Cu(II)
$Cu(II)
$Cu(II)
Cu(II) in the ESI source, as a small cluster of peaks centred
at m/z 936.5. The visible spectra display absorption bands
consistent with copper(II)–N chromophores for these com-
4
1
5,21,38,39
plexes.
Their lmax and 3 are given in Table 2 and
compared to those of the tetra-N-methylcyclam copper com-
plex (TMC$Cu(II)). The red shifts of absorption bands
Figure 1. Molecular structure of 6. ORTEP diagram.
(
4
Dlmax 67–74 nm) observed in the case of complexes
$Cu(II) and 5$Cu(II) when compared to the TMC complex
are consistent with an axial coordination of one or two sulf-
8
2% overall yield. The crystals were suitable for X-ray dif-
1
5,21,38,39,47
oxide groups to the central metal ion.
On the
fraction analysis and the resulting crystallographic structure
confirms the tetrasubstituted structure with a trans relative
arrangement of the pendant groups (Fig. 1). As observed
for compounds 4 and 5, the symmetry of the molecule can
other hand, the absorption band of complex 6$Cu(II) is close
to that of TMC$Cu(II) suggesting that the sulfonyl pendant
groups do not coordinate to Cu.
1
be inferred from the number of signals in the H NMR
Reaction of either tetrasulfinyl macrocycles 4 or 5 with
1 equiv of europium nitrate in ethanol led to the formation
of insoluble brown powders. The IR spectra of the two solids,
(
five signals for the methylene protons vs three aromatic sig-
nals) and C NMR spectra.
1
3
ꢁ
1
4
$Eu(III) and 5$Eu(III), showed bands at 1030 cm result-
2
.2. Coordination properties of macrocycles 4–6
ing from the stretching vibration of the S]O group. The shift
of n(S]O) to lower wavenumbers compared to that of free
The coordination chemistry of cyclam has been widely stud-
ied, owing to its high binding affinity for transition metals
ꢁ
1 48
ligands 4 and 5 (1038 cm ) suggests coordination through
the oxygen atoms of the S]O moieties of the pendant arms,
1
,2,8
and its marked selectivity for cupric ions.
tetra-N-alkylated ligands derived from cyclam and their cop-
A number of
4
2
as was already reported with classical sulfoxides. The IR
spectra also reveal the presence of nitrate anions coordinated
in a bidentate and monodentate manner at 1480, 1385 and
per complexes, in which the metal is coordinated to the four
nitrogen atoms, have been described in the literature.
1
,2,8,21,38
ꢁ
1 49
1
300 cm
.
The fluorescence spectra of the solids,
In some cases, axial coordination of Cu by one or two
auxiliary coordinating groups like amide, carboxylate, amine
or pyridine attached on the side chains has been
recorded at room temperature, further demonstrate the
presence of europium. These spectra show the three
characteristic emission bands for Eu(III) at 593, 619 and
1
,2,9,22,39,40
reported.
On the other hand, cyclam does not
5
7
1
2
6
96 nm, corresponding to the D / F (J¼1, 2, 4) transi-
form complexes with rare earth cations and Ln complexes
have only been described with cyclam derivatives appended
with additional oxygen donor coordinating groups on side
0
J
1
1,43,49,50
tions, upon excitation at 466 or 396 nm (Fig. 2).
emental analyses of the solid 4$Eu(III) are consistent with
a Eu L (NO ) composition and are indicative of the coordi-
El-
1
–6,9,10
6
3–5,9,10
9,12
chains.
like carboxylates,
amides
or phos-
3
2
3 3
nation of two or three sulfoxide groups and three nitrates per
phonates groups. SO groups are known strong oxygen donor
coordinating groups and numerous coordination compounds
of transition metals and rare earth elements with various sulf-
4
1–46
200
oxides have been reported.
We have therefore investi-
1
80
gated the coordination properties of macrocycles 4–6
appended with four sulfinyl or sulfonyl groups, that might
act as auxiliary ligands, towards Cu(II) and Eu(III).
160
140
1
1
20
00
Macrocycles 4–6 readily form complexes with copper ni-
trate: the tetrasulfinyl macrocycles 4 and 5 furnished
Cu(II) complexes, 4$Cu(II) and 5$Cu(II), as green powders
after concentration of the reaction mixtures whereas the sul-
fonyl complex 6$Cu(II) conveniently precipitated out of the
reaction medium as a blue powder. Elemental analyses are
consistent with a 1:1 stoichiometry for the complexes. The
ESI-MS spectra show the base peaks, with the expected iso-
8
6
4
2
0
0
0
0
0
5
80
600
620
640
660
/ nm
680
700
720
2
+
topic pattern, at m/z 435.5 and 436.5 for 4$Cu and 463.5
and 464.5 for 5$Cu . The mass spectrum of 6$Cu(II) shows
the monocharged ion 6$Cu , resulting from a reduction of
2+
Figure 2. Solid state fluorescence emission spectrum (room temperature) of
coordination compound 4$Eu(III) with excitation at 396 nm.
+

A. de Castries et al. / Tetrahedron 63 (2007) 10330–10336
10333
Eu. This 1.5 Eu-per-macrocycle stoichiometry strongly sug-
gests that the macrocyclic tetrasulfoxide ligands act as
bridges to link adjacent Eu(III) ions giving rise to polymeric
assemblies, similar to those recently reported in lanthanide
on a Perkin–Elmer 341 digital polarimeter at l¼589, 578,
ꢀ
on silica plates (Merck 60F254) with Cu(NO ) $3H O
546 and 436 nm at 25 C. TLC analyses were performed
3 2
2
(0.2% in absolute ethanol) as the revelator for the free li-
gands. Column chromatography was carried out with silica
gel Chromagel 60 A C.C (70–200 mm) from SDS. Melting
points were determined on a Mettler FP61 melting point ap-
paratus. The UV–vis spectra were recorded on a Lambda 19
spectrophotometer (Perkin–Elmer). Fluorescence measure-
44,45
coordination polymers with bis and tris sulfoxides.
A
close composition is obtained with ligand 5 with a slightly
higher Eu-to-macrocycle molar ratio. All these characteris-
tics are indicative of the coordination of Eu(III) by ligands
4 and 5 through the oxygen atoms of their pendant sulfoxide
groups.
ꢀ
Ò
ments were made at 25 C using a FluoroMax -3 spectro-
fluorometer equipped with 150 W xenon lamp. Solid
fluorescence spectra were measured with a reflexion angle
On the other hand, when macrocycle 6, bearing four ethyl-
phenylsulfonyl pendant arms, was reacted with Eu(NO3)3
no precipitate was formed and there was no spectroscopic
evidence for the formation of coordination complexes.
These latter features indicate that sulfonyl groups do not
coordinate to Eu ions.
ꢀ
of 45 with a recording rate adjusted to 10 nm/s upon exci-
tation at 396 and 466 nm.
4.1.1. (R)-p-Tolyl vinyl sulfoxide 3. (R)-p-Tolyl vinyl sulf-
oxide was prepared using an experimental procedure slightly
adapted from Ref. 36. A solution of (1R,2S,5R)-menthyl
(
S)-p-toluenesulfinate (33.9 mmol, 10 g) was dissolved in
3
. Conclusions
100 mL of distilled diethyl ether and placed under argon. Vi-
nyl magnesium bromide (33.9 mmol, 1 M in THF, 33.9 mL)
was rapidly added at room temperature. After stirring the re-
action mixture for 10 min, a saturated solution of ammonium
chloride (30 mL) was added. The aqueous layer was
extracted with dichloromethane (4ꢂ150 mL) and the com-
bined organic layers were washed with brine (100 mL),
Aza-Michael addition is a very convenient method to pre-
pare substituted cyclam derivatives appended with four sul-
fonyl and sulfinyl groups. Since numerous vinylsulfones and
vinylsulfoxides are readily accessible through well-docu-
mented synthetic processes, this strategy is expected to be
quite general and should give access to a variety of function-
alised azamacrocycles. Interestingly, optically active macro-
cycles are easily obtained from enantiomerically pure
vinylsulfoxides.
dried with MgSO , filtered and rotary evaporated. The crude
4
ꢀ
(0.25 mbar) to yield a yellow oil (5.65 g, 59%). R : 0.5 (pen-
product was distilled off at 67–70 C under reduced pressure
f
2
5
tane/ethyl acetate 1/1; revelator: KMnO ). [a] 413 (c 1.65,
4
acetone) (lit. [a]D 446 (c 1.65, acetone)). The H NMR
spectrum is in agreement with the literature.
D
3
6
25
1
3
6
The preliminary studies of the coordination properties of the
cyclam derivatives bearing ethylphenysulfonyl and ethylar-
ylsulfinyl pendant arms indicate that the sulfoxides act as
coordinating groups whereas we do not get any evidence
for the participation of sulfonyl groups. In copper(II) com-
plexes, the sulfoxide pendant arms act as auxiliary coordi-
nating groups in addition to the four macrocyclic nitrogen
atoms. In coordination compounds with europium(III) the
sulfinyl functionalised macrocycles act as polydentate li-
gands and lead to supramolecular assemblies.
4.1.2. 1,4,8,11-Tetrakis-(2-phenylsulfinyl-ethyl)-1,4,8,11-
tetraazacyclotetradecane 4. Phenyl vinyl sulfoxide 2
(2.5 mmol, 0.33 mL) was added to a solution of cyclam
(0.5 mmol, 100 mg) in a mixture of isopropanol and water
(1.3 mL/0.6 mL). The reaction mixture was refluxed for
24 h, concentrated and purified through column chromato-
graphy (ether followed by dichloromethane/methanol 1/1)
to yield a brownish powder (0.38 mmol, 309 mg, 75% yield).
ꢀ
R : 0.8 (CH Cl /MeOH 65/35); mp 132.1 C. Anal. Found:
f
2
2
Potential applications of the macrocyclic ligand 5 appended
with enantiomerically pure sulfinyl groups in asymmetric
catalysis are currently under investigation.
C, 60.30; H, 7.10; N, 6.68. Calcd for C H N O S $2H O:
42 56 4 4 4 2
C, 60.30; H, 7.15; N, 6.62%; l
(3/dm mol cm 166), 280 (968); nmax/cm (KBr pellet):
(DMF)/330 nm
max
3
ꢁ1
ꢁ1
ꢁ1
ꢁ1
3050, 2955, 1640, 1439, 1038 (S]O), 748, 691, 518 cm
dH (200 MHz; CDCl ) 1.64 (4H, m, CH CH CH ), 2.60–
;
3
2
2
2
4
. Experimental section
2.99 (32H, m, CH N, CH SO), 7.49–7.50 (CH ); d
2 2 Ar c
(75 MHz; CDCl ) 23.9 (CH CH CH ), 47.3, 51.2, 51.3,
3 2 2 2
4
.1. General
55.0, 123.8, 129.8, 130.7 (C H), 144.0 (C S); m/z (ESI
Ar Ar
pos) 809 [(M+H) ] (100%), 831 [(M+Na) ] (50).
+
+
All chemicals were purchased from Sigma, Aldrich or Fluka
and were used without further purification. Organic solvents
were purchased from SDS. IR spectra were recorded on an
4.1.3. 1,4,8,11-Tetrakis-(2-p-tolylsulfinyl-ethyl)-1,4,8,11-
tetraazacyclotetradecane 5. (R)-p-Tolyl vinyl sulfoxide 3
(2.5 mmol, 380 mg, 0.33 mL) reacted with cyclam
(0.5 mmol, 100 mg) following the above procedure for 4.
Purification by column chromatography (ether followed by
dichloromethane/methanol 1/1) gave 5 as a brownish pow-
der (0.39 mmol, 298 mg, 69% yield). R : 0.8 (CH Cl /
1
13
Impact 400D Nicolet spectrophotometer. H NMR and
NMR spectra were acquired on a Bruker AC300 (300,
5 MHz) or on a Bruker AC200 (200, 50 MHz) spectrometer
using the residual peak of CHCl or CDCl (7.27, 77 ppm) as
C
7
3
3
internal standards. Electrospray mass spectra (positive
mode) were obtained on an HP MS Engine 5989B spectrom-
eter. Elemental analyses were obtained from the Service
Central d’Analyses du CNRS (Vernaison, France) or ICSN
f
2
2
ꢀ
25
25
MeOH 65/35); mp: 135–137 C; [a] 157, [a]
165,
578
D
2
5
46
25
[a]
192, [a]
383 (c 5.76, ethanol). Anal. Found: C,
436
5
62.34; H, 7.38; N, 6.19. Calcd for C H N O S $1H O:
4
6
64
4
4
4
2
ꢁ
1
(
Gif-sur-Yvette, France). Optical rotations were measured
C, 62.55; H, 7.53; N, 6.34%; nmax/cm (KBr pellet) 3448,

10334
A. de Castries et al. / Tetrahedron 63 (2007) 10330–10336
2
949, 1644, 1493, 1455, 1084, 1038 (S]O), 811; dH
200 MHz; CDCl ) 1.66 (4H, m, CH CH CH ), 2.42 (12H,
F(000)¼928, 14,871 reflections measured, of which 5663
were independent (2589 F >4s(F )), 263 refined para-
(
s, PhMe), 2.61 (16H, m, NCH ), 3.00 (16H, m, NCH and
3
2
2
2
o
o
meters, R ¼0.0586, wR ¼0.1057, GOF¼0.996; max./min.
2
2
1
2
˚
ꢁ3
CH SO), 7.30 (8H, d, J¼8.1, CH ), 7.54 (8H, d, J¼8.1,
residual electron density 0.229/ꢁ0.284 e A
.
2
Ar
CH );
(
d
CH CH CH ), 47.4, 51.2, 51.5, 55.1 (CH N), 123.7,
(75 MHz; CDCl ) 21.2 (CH ), 23.7
Ar
c
3
3
4.1.6. 1,4,8,11-Tetrakis-(2-phenylsulfinyl-ethyl)-1,4,8,11-
tetraazacyclotetradecane copper(II)nitrate 4$Cu(II).
Copper nitrate trihydrate (0.177 mmol, 42.8 mg) was added
to a solution of macrocycle 4 (0.177 mmol, 143 mg) in a mix-
ture of dichloromethane and methanol (3 mL/1 mL). The re-
sulting reaction mixture was stirred at room temperature
over a period of 18 h and concentrated to dryness to yield
a green powder (0.177 mmol, 179 mg); mp: decomposition
2
2
2
2
1
8
29.9 (C H), 144.8, 141.4 (C S, C Me); m/z (ESI pos)
Ar Ar Ar
+
+
65 [(M+H) ] (100%), 887 [(M+Na) ] (20).
4
1
1
.1.4. 1,4,8,11-Tetrakis-(2-phenylsulfonyl-ethyl)-
,4,8,11-tetraazacyclotetradecane 6. Phenyl vinyl sulfone
(1.67 g, 10 mmol) was added to a solution of cyclam
(
(
200 mg, 1 mmol) in a mixture of isopropanol and water
8 mL/4 mL). The reaction mixture was stirred at room
ꢀ
at 148–150 C. Anal. Found: C, 46.58; H, 5.73; Cu, 6.51;
N, 8.05. Calcd for C H N O S Cu$4H O (CuL-
temperature for 7 h. The desired product precipitated out
of the reaction mixture and was collected by filtration. It
was washed with 15 mL of methanol. Crystallisation by
slow diffusion of 15 mL of methanol carefully added to
7
white crystals (709 mg, 82%). R : 0.8 (CHCl /MeOH 9/1);
4
2
56
6
10
4
2
(NO ) $4H O) C, 46.81; H, 6.07; Cu, 5.90; N, 7.80%;
2
3
2
3
ꢁ1
ꢁ1
lmax (EtOH)/731 nm (3/dm mol cm 316), 327 nm
(6312), 247 nm; nmax/cm (KBr pellet) 2940, 1640, 1480,
1383, 1086, 1040 (S]O), 748, 697 cm ; ESI (pos mode)
m/z: 435.5–436.5 [(4$Cu) ] (100), 373–374 [(4$Cu)–
SOC H ] (25), 933–935 [4$CuNO ] (10).
6 5 3
ꢁ1
ꢁ
1
73 mg of the white powder in 70 mL of chloroform gave
2
+
f
3
ꢀ
2+
+
mp 178 C. Anal. Found: C, 57.51; H, 6.85; N 6.32. Calcd
for C H N O S : C, 57.77; H, 6.46; N, 6.42%; nmax/
4
2 56 4 8 4
ꢁ1
cm (KBr pellet) 3059, 2962, 2936, 2817, 1583 (C]C),
475, 1440, 1301 (SO2 asym), 1142 (SO2 sym); dH
200 MHz; CDCl ) 1.35 (4H, m, CH CH CH ), 2.31
4.1.7. 1,4,8,11-Tetrakis-(2-p-tolylsulfinyl-ethyl)-1,4,8,11-
tetraazacyclotetradecane copper(II) nitrate 5$Cu(II).
Prepared as described above from 5 (0.486 mmol,
420 mg). A green powder (0.486 mmol, 520 mg) was ob-
1
(
(
3
2
2
2
16H, m, CH CH CH N, NCH CH N), 2.79–2.84 (m, 8H,
2
2
2
2
2
ꢀ
tained. Mp: decomposition at 154–156 C; [a] 78, [a]
D 578
25
25
NCH CH SO), 3.13–3.18 (m, 8H, CH SO), 7.59 (m, 8H,
2
H ), 7.68 (4H, m, H ), 7.91 (8H, m, H ); d (75 MHz;
m
2
2
2
5
102, [a] 194 (c 1.0, ethanol). Anal. Found: C, 51.08;
546
p
o
c
CDCl ) 24.2 (CH CH CH ), 47.1 (NCH CH SO ), 50.7
2
H, 6.14; N, 7.77; Cu, 5.92. Calcd for C H N O S Cu$
46 64 6 10 4
3
2
2
2
2
2
(
CH CH CH N, NCH CH N), 52.6 (CH SO ), 127.9 (C ),
2
1.5H O (CuL(NO ) $1.5H O): C, 51.17; H, 6.25; N,
2 3 2 2
2
2
2
2
2
2
o
3
ꢁ1
ꢁ1
1
m/z: 873 [(M+H) ] (100).
29.4 (C ), 133.8 (C ), 139.6 (Cipso); FAB (pos mode)
7.78; Cu, 5.88%; lmax (EtOH)/738 nm (3/dm mol cm
297), 321 nm (4160), 256 nm; nmax/cm
m
p
+
ꢁ1
(KBr pellet)
3
(S]O), 1014, 815 cm ; ESI (pos mode) m/z: 463.5–
421, 2925, 2720, 1644, 1480, 1379 (NO ), 1086, 1040
3
ꢁ
1
4
.1.5. Crystal structure determination. A white platelet
3
2+
2+
(0.50ꢂ0.10ꢂ0.02 mm ) was analysed with a Siemens
SMART three-circle diffractometer equipped with a CCD
464.5 [5$Cu ] (100), 394–395 [5$Cu–SOTol]
989–991 [5$CuNO ] (10).
(25),
+
3
bidimensional detector with Mo Ka monochromatised radi-
˚
ation (l¼0.71073 A). Slightly more than one hemisphere of
4.1.8. 1,4,8,11-Tetrakis-(2-phenylsulfonyl-ethyl)-1,
4,8,11-tetraazacyclotetradecane copper(II) nitrate
data was collected in 1271 frames with u scans (width of
0
ꢀ
ꢁ2
.30 and exposure time of 30 s per frame). Data reduction
6$Cu(II). Prepared by reacting 6 (3.43ꢂ10 mmol,
ꢁ
2
was performed with SAINT software. Data were corrected
for Lorentz and polarisation effects and the absorption cor-
rection was based on multiple and symmetry-equivalent re-
30 mg) with copper nitrate (3.4ꢂ10 mmol, 8 mg) in
3 mL dichloromethane for 18 h at room temperature. Com-
ꢁ2
plex 6$Cu precipitated as a blue powder (3.3ꢂ10 mmol,
35 mg, 96%). Anal. Found: C, 45.36; H, 5.14; N, 7.68; Cu,
5.82. Calcd for C H N S O Cu$2.5H O (CuL-
5
1
flections in the data set by using the SADABS program
based on the method of Blessing. Lattice parameters were
obtained from least-squares analysis of all reflections. The
structure was solved by direct method and refined by full
4
2
56
6
4
14
2
(NO ) $2.5H O): C, 45.62; H, 5.56; N, 7.60; Cu, 5.74%;
3
2
2
3
ꢁ1
ꢁ1
ꢁ1
lmax (MeOH)/659 nm (3/dm mol cm 244); nmax/cm
(KBr pellet) 2979–2924, 1301 (SO asym), 1146 (SO
sym); ESI (pos mode) m/z: 873 [6$H ] (100), 895 [6$Na ]
2
matrix least-squares, based on F , using the SHELX-TL
2
+
2
+
5
2
software package. All non-hydrogen atoms were refined
with anisotropic displacement parameters. All hydrogen
atoms were located with geometrical restraints in the riding
mode.
+
(37), 935 (14)–936 (6)–937 (9)–938 (6) [(6$Cu) ].
4.1.9. Coordination complex of Eu with macrocycle 4
$Eu(III). Europium nitrate pentahydrate (1.84 mmol,
4
Crystallographic data for the structure reported in this paper
have been deposited at the Cambridge Crystallographic Data
Centre as supplementary publication no. CCDC 644941. Cop-
ies of the data can be obtained free of charge on application to
CCDC, 12 Union Road, Cambridge CB21EZ, UK (fax:
787 mg) was added to a solution of 4 (1.84 mmol, 1.486 g)
in absolute ethanol (16 mL) and the resulting solution was
stirred at room temperature for 10 min, then diluted with ab-
solute ethanol (21 mL) and stirred for 18 h. The precipitated
powder was isolated by filtration, washed with ethanol
(100 mL) and then with methanol (100 mL) to yield
(
+44)1223-336-033; e-mail: deposit@ccdc.cam.ac.uk).
605 mg of a brown powder. Mp: decomposition at 153–
154 C. Anal. Found: C, 35.53; H, 4.34; Eu, 15.94; N,
˚
ꢀ
8.02. Calcd for [Eu L (NO ) $12H O] C, 35.42; H, 4.81;
Eu, 16.01; N, 8.36%; nmax/cm (KBr pellet) 3416, 2955,
Monoclinic, space group P2 /c, a¼5.6755(2) A, b¼11.3204
1
˚
˚
ꢀ
(
1) A, c¼33.2829(5) A, b¼91.021(1) , V¼2138.05(8)
3
2
3 9
2
˚
3
ꢁ3
ꢁ1
ꢁ1
A , Z¼2, r
¼1.356 g cm , m(Mo Ka)¼0.279 mm
,
calcd

A. de Castries et al. / Tetrahedron 63 (2007) 10330–10336
10335
1
634, 1480 (NO ), 1383 (NO ), 1309 (NO ), 1086, 1030
3
15. de Castries, A.; Magnier, E.; Monmotton, S.; Fensterbank, H.;
Larpent, C. Eur. J. Org. Chem. 2006, 20, 4685–4692.
3
3
ꢁ
1
(
S]O), 748, 682 cm
.
1
6. Pozzi, G.; Cavazzini, M.; Quici, S. Tetrahedron Lett. 1997, 38,
7605–7608.
4
5
.1.10. Coordination complex of Eu with macrocycle 5
$Eu(III). Prepared as described above from
5
17. Larpent, C.; Laplace, A.; Zemb, T. Angew. Chem., Int. Ed.
2004, 43, 3163–3167; Larpent, C.; Laplace, A.; Zemb, T.
Angew. Chem. 2004, 116, 3225–3229.
18. Arleth, L.; Posselt, D.; Gazeau, D.; Larpent, C.; Zemb, T.;
Mortensen, K.; Pedersen, J. S. Langmuir 1997, 13, 1887–1896.
19. (a) Fensterbank, H.; Berthault, P.; Larpent, C. Eur. J. Org.
Chem. 2003, 20, 3985–3990; (b) Fensterbank, H.; Zhu, J.;
Riou, D.; Larpent, C. J. Chem. Soc. Perkin Trans. 1 1999,
811–816; (c) Gaudinet-Hamann, B.; Zhu, J.; Fensterbank, H.;
Larpent, C. Tetrahedron Lett. 1999, 40, 287–290.
(
0.499 mmol, 431 mg). Brown powder (175 mg). Mp: de-
ꢀ
composition at 167–169 C. Anal. Found: C, 33.06; H,
.34; Eu, 19.93; N, 7.40. Calcd for [Eu L (NO ) $12H O]:
C, 32.46; H, 5.20; Eu, 20.09; N, 6.99%; nmax/cm (KBr pel-
4
9
4
3 18
2
ꢁ
1
let) 3398, 1635, 1480 (NO ), 1384 (NO ), 1309 (NO ), 1085,
3
3
3
ꢁ1
1
030 (S]O), 1004, 813 cm
.
4
.1.11. Attempts to prepare coordination complex of Eu
with macrocycle 6. Macrocycle 6 is not soluble in ethanol.
Complexation was attempted by addition of europium
nitrate pentahydrate to a solution of 6 in a mixture of chlo-
roform and acetonitrile. No precipitate was observed.
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2
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Supplementary data
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j.tet.2007.07.067.
1
991, 30, 572–575.
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