Synthesis of ferrocenoyl amino acid derivatives via homogeneous catalytic aminocarbonylation

Article abstract of DOI:10.1016/j.jorganchem.2005.03.054

Palladium-catalysed aminocarbonylation of iodoferrocene with amino acid esters as nucleophiles results in the selective formation of N-ferrocenoyl amino acid esters in the presence of Et₃N as the base. At the same time, the use of DBU leads to

Full text of DOI:10.1016/j.jorganchem.2005.03.054

Journal of Organometallic Chemistry 690 (2005) 3237–3242
www.elsevier.com/locate/jorganchem
Synthesis of ferrocenoyl amino acid derivatives via
homogeneous catalytic aminocarbonylation
a
Arpad Kuik , Rita Skoda-Fo¨ldes
a,b,
a
´ ´ ´ ´
, Janos Balogh , Laszlo Kollar
c
´
*
´
a
´ ´
University of Veszprem, Department of Organic Chemistry, P.O. Box 158, H-8201 Veszprem, Hungary
b
´
Research Group for Petrochemistry of the Hungarian Academy of Sciences, P.O. Box 158, H-8201 Veszprem, Hungary
c
´ ´
University of Pecs, Department of Inorganic Chemistry, P.O. Box 266, H-7624 Pecs, Hungary
Received 20 December 2004; revised 7 March 2005; accepted 7 March 2005
Available online 17 May 2005
Abstract
Palladium-catalysed aminocarbonylation of iodoferrocene with amino acid esters as nucleophiles results in the selective forma-
tion of N-ferrocenoyl amino acid esters in the presence of Et3N as the base. At the same time, the use of DBU leads to the formation
of new N-ferrocenylglyoxyl amino acid derivatives with reasonable selectivity. In the latter reactions two new side products, formed
via acylation of DBU, were also isolated and characterised.
Ó 2005 Elsevier B.V. All rights reserved.
Keywords: Ferrocene; Amino acids; a-Ketoamides; Carbonylation; Pd-catalysts
1. Introduction
of our knowledge there is no precedence for the synthe-
sis of N-ferrocenoyl amino acids with palladium-cataly-
sed aminocarbonylation.
In the past few years, numerous electrochemical bio-
sensors have been developed for the analytical determi-
nation of biological analytes [1–4]. Good stability and
favourable electrochemical properties makes ferrocene
derivatives good candidates for such purposes. Ferro-
cene-derived devices are used as anion and cation sen-
sors [5,6], DNA biosensors [7–9] and as mediators of
the electron transfer between active sites of oxidoreduc-
tases (e.g., glucose oxidase [10]) and electrodes. As a re-
sult, several methods have been reported for the
synthesis of ferrocene-linked biomolecules, especially
amino acids and peptides [11–18].
Carbonylation of aryl halides in the presence of pri-
mary and secondary amines is a well-explored method
for the selective synthesis of aryl amides and aryl ketoa-
mides [21–23]. According to our recent results, amino
acid esters can be successfully used as nucleophiles in
the aminocarbonylation of iodobenzene and alkenyl
iodides [24]. Therefore, as the next step in our series of
investigations concerning the carbonylation reactions
of iodoferrocene derivatives [25–28], the aminocarbony-
lation of iodoferrocene in the presence of amino acid es-
ters has been explored.
Although iodoferrocene has been used as substrate
for the synthesis of protected ferrocenyl-alanine ((2-ami-
no-2-carboxyethyl)ferrocene) derivatives via homoge-
neous catalytic coupling reactions [19,20], to the best
In this reaction, N-ferrocenoyl amino acids can be
synthesised via acylation of amino acid esters with the
acyl-palladium intermediate formed in situ from the pal-
ladium precursor, carbon monoxide and iodoferrocene.
As iodoferrocene can be readily produced from ferro-
cene via lithiation [29], this method is a good alternative
of the generally used DCC/HOBt protocol starting from
ferrocenecarboxylic acid [11–15].
*
Corresponding author. Tel.: +36 88 624719/422022; fax: +36 88
624469/427492.
E-mail address: skodane@almos.vein.hu (R. Skoda-Fo¨ldes).
0022-328X/$ - see front matter Ó 2005 Elsevier B.V. All rights reserved.
doi:10.1016/j.jorganchem.2005.03.054

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A. Kuik et al. / Journal of Organometallic Chemistry 690 (2005) 3237–3242
3238
In the present work, it is also shown that in the
the prevailing product). As a favourable effect of DBU
on a-ketoamide formation has been reported by Inoue
and co-workers [30], the carbonylation reaction has
been carried out in the presence of various amounts
of DBU (Runs 3–6, Table 1). As a result, the a-ketoa-
mide/amide ratio has been increased, but the total yield
observed by GC decreased simultaneously in spite of
the total conversion of iodoferrocene in each case. It
should be noted that the low values of GC yields are
due to three facts according to the further investiga-
tions described in Section 2.2: (i) the formation of side
products 8a,b; (ii) decomposition of amide and ketoa-
mide derivatives in the presence of DBU under non-
inert conditions; and (iii) partial decomposition of the
products in the presence of DBU in the inlet of the
gas chromatograph.
aminocarbonylation of iodoferrocene, by the proper
choice of the reaction conditions, new N-ferrocenylgly-
oxyl amino acid derivatives can also be obtained.
2. Results and discussion
2.1. Carbonylation of iodoferrocene in the presence of
methyl glycinate
Our previous results concerning the aminocarbonyla-
tion of iodoferrocene with secondary amines [25,26] and
that of iodobenzene with amino acid esters [24] demon-
strated that both amide- and a-ketoamide-type products
could be obtained in these reactions depending on the
O
R2
O
R1
N
O
R2
OMe
I
N
OMe
Pd(OAc)2 + 2 PPh3
OMe
R2
R1HN
Fe
R1
O
O
R2
+
CO
+
+
Fe
Fe
O
THF, base
40 bar
R1
ð1Þ
1
2a
2b
2c
H
H
H
H
CH3
CH2Ph
(Gly-OMe)
(L-Ala-OMe)
(L-Phe-OMe)
3a-e
4a-e
2d
2e
H
(CH2)2SCH3 (L-Met-OMe)
(L-Pro-OMe)
-CH2CH2CH2-
reaction conditions. Optimal conversion was achieved
at 40–50 bar CO pressure. The use of relatively low tem-
peratures (40–60 °C) favoured the formation of a-ketoa-
mides, while amides were formed with high selectivity at
100 °C in most cases.
Accordingly, iodoferrocene (1) was reacted with a
fivefold excess of methyl glycinate in the presence of
an in situ Pd-catalyst (5 mol%) in an autoclave under
CO pressure (Eq. (1)). At 100 °C and 40 bar CO pres-
sure, complex 1 could be converted selectively into 3a
(Table 1).
2.2. Synthesis of N-ferrocenoyl- and N-ferrocenylglyoxyl
amino acid esters
Based on the results described above, reaction condi-
tions corresponding to Runs 1 and 4 in Table 1 were
chosen for the synthesis of amides 3a–e and ketoamides
4a–e, respectively (Eq. 1, Table 2). The products were
isolated and purified by column chromatography.
N-Ferrocenoyl amino acid esters 3a–e were produced
in excellent yields using Et3N as base (Table 2, Runs 1,
4, 7, 10, and 13). However, in the presence of DBU only
moderate amounts of the N-ferrocenylglyoxyl deriva-
tives 4a–e could be isolated (Runs 2, 5, 8, 11, and 14).
According to the analysis of the reaction mixtures by
However, contrary to the reactions of iodobenzene
[24], the decrease in the temperature led to just a small
increase in the ratio of 4a to 3a (but 3a still remained
Table 1
Carbonylation of iodoferrocene in the presence of methyl glycinate (2a)a
Run
Base
Base/Fc–I (mol/mol)
T (°C)
Run time (h)
Conversionb (%)
Yieldb (%)
3a
4a
1
2
3
4
5
6
a
Et3N
Et3N
DBU
DBU
DBU
DBU
6
6
100
60
8
8
100
82
100
73
58
9
0
9
6
100
100
60
8
100
100
99
4
8
8
32
13
12
8
10
12
2
8
100
100
4
40 bar CO.
Determined by GC with eicosane as internal standard.
b

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A. Kuik et al. / Journal of Organometallic Chemistry 690 (2005) 3237–3242
3239
Table 2
Carbonylation of iodoferrocene in the presence of amino acid esters
and 162.1 ppm) in the 160–190 ppm region were as-
signed to two DBU-derived amide- and ketoamide-type
products, respectively.
(2a–2e)a
Run Nucleophile Base
Conversionb (%) Isolated yield (%)
According to the literature, DBU can be acylated
with dimethyl- or dibenzyl carbonate [31,32] or can
be alkylated with alkyl halides [33] leading to the cor-
responding salts. However, in the alkylation reaction a
side product, formed by the opening of the bridge of
the bicyclic compound, was also obtained. Another
possibility is the hydrolysis of the salt leading to a hy-
droxy derivative, as it was observed for a reaction of
DBU that took place in the coordination sphere of
ruthenium [34]. Considering these observations, the
carbonylation reaction of iodoferrocene with DBU
as nucleophile may lead to products 8a,b or 9a,b
(Scheme 1).
The appearance of the two and three singlets in the
160–190 ppm region of the respective 13C NMR spectra
unambiguously show the formation of 8a and 8b. The
high downfield shift of the NH protons (7.38 ppm for
8a and 8.00 ppm for 8b) is probably due to the forma-
tion of a hydrogen bond between the NH and the
2-CO group.
3
4
8a + 8b
1
2
2a
2a
2a
2b
2b
2b
2c
2c
2c
2d
2d
2d
2e
2e
2e
Et3Nc
DBUd
DBUe
Et3Nc
DBUd
DBUe
Et3Nc
DBUd
DBUe
Et3Nc
DBUd
DBUe
Et3Nc
100
99
99
92
99
99
85
97
96
81
98
98
90
94
1
–
–
2
5
–
25
89
–
3
1
87
4
5
17 20 14
23 28 21
6
7
81
2
–
10 29
–
8
9
15 26 42
10
11
12
13
14
15
a
75
3
–
–
17 19
37 32
4
84
–
–
DBUd 100
DBUe 100
32 29 3
32 30 19
Reaction conditions: 40 bar CO, 100 °C, amino acid ester/1 = 5,
8 h.
b
Determined by GC with eicosane as internal standard.
Et3N/1 = 6.
c
d
e
DBU/1 = 8.
DBU/1 = 8, during purification removal of DBU was carried out
under inert conditions.
It should be noted that when carbonylation of iodo-
ferrocene is carried out in the presence of DBU alone
(i.e., DBU itself serves as a nucleophile), without the
addition of any amino acid esters, 8a is the main product
and 8b is formed in traces only. On the contrary, in the
reactions with amino acid esters, 8b can be produced
with good selectivity.
TLC, in addition to the expected products 3a–e and 4a–
e, considerable amounts of a pair of ferrocene deriva-
tives were also formed. The same novel compounds were
obtained in all cases when DBU was used, irrespective of
the amino acid ester nucleophile.
These compounds were also isolated and their struc-
ture were determined using various spectroscopic meth-
ods (1H, 13C NMR, correlation spectra (1H–1H and
1H–13C), MS and IR). The NMR spectra of these deriv-
atives have shown the formation of two very similar fer-
rocene derivatives. In the 13C NMR spectra of these
compounds eight singlets appeared in the 20–50 ppm re-
gion corresponding to methylene groups. Two (at 177.2
and 170.2 ppm) and three further signals (at 190.9, 176.5
A careful examination of the reaction mixtures con-
taining DBU showed the decomposition of amide and
ketoamide type products (except 3e and 4e) in air. As
no decomposition was observed in the THF solutions
of the isolated compounds, in the further experiments
the first step of the purification procedure, the removal
of DBU was carried out under inert conditions. As a re-
sult, isolated yields were improved considerably in most
cases (Table 2, Runs 3, 6, 9, 12, and 15).
I
[Pd]
Fe
+
CO +
N
-
I
+
N
N
Fc
C
O
N
n
7a n=1
7b n=2
Fc-I (1)
DBU
O NH
HO
N
Fc
C
O
N
n
Fc
C
O
N
n
9a,b
8a,b
Scheme 1. Possible products of carbonylation of iodoferrocene in the presence of DBU.

´
A. Kuik et al. / Journal of Organometallic Chemistry 690 (2005) 3237–3242
3240
It should be noted that decomposition of amides and
During the work-up of the reaction mixture the vola-
tile components were removed in vacuo. The residue was
dissolved in toluene (20 mL), washed with 5% H3PO4
(20 mL), saturated aqueous NaHCO3 (20 mL) and brine
(20 mL) and dried over Na2SO4.
Alternatively, toluene (20 mL) was added to the reac-
tion mixture after the completion of the reaction and the
first washing with 5% H3PO4 (20 mL) was carried out
under an inert atmosphere. After that, the procedure
was the same as above.
ketoamides in the presence of DBU was also observed
under the conditions of gas chromatography. The de-
crease of the GC-yields with increasing amount of
DBU as shown in Table 1. Runs 3–6 is partly due to this
breakdown. At the same time, no decomposition of 3a–
3d and 4a–4d took place in the absence of DBU. The
starting material, iodoferrocene was inert both in the
presence and in the absence of DBU.
The N-ferrocenylglyoxyl derivative 4a can be pro-
duced with high selectivity using methyl glycinate as
the nucleophile (Table 2.). DBU successfully competes
with the other amino acid esters in the reaction with
the acylpalladium intermediate, which results in the for-
mation of considerable amounts of 8a,b.
The products were separated after removal of the sol-
vent by column chromatography (aluminium oxide, tol-
uene/EtOAc = 3/1 for 3a–e and 4a–e, EtOAc/
MeOH = 10/1 for 8a,b). The structures of the isolated
1
compounds were determined by H, 13C NMR and IR
The a-ketoamide/amide ratio (4/3) is the lowest in the
reaction of methyl L-prolinate. This is in accordance
with our previous results that have shown that ketoa-
mide formation is not favoured in the reactions of the
sterically hindered nucleophiles [26].
spectroscopy, elemental analysis, and MS.
Physical properties and spectra of 3a–c corresponded
well to the literature data [35].
4.1.1. N-Ferrocenoyl-L-methionine methyl ester (3d)
1H NMR(CDCl3) d: 6.45 (brs, 1H, NH); 4.85 (m, 1H,
CH); 4.71 (brs, 1H, Cp-2); 4.65 (brs, 1H, Cp-5); 4.34
(brs, 2H, Cp-3,4); 4.21 (s, 5H, Cp); 3.77 (s, 3H,
OCH3); 2.55 (t, 7 Hz, S–CH2); 2.3-1.9 (m, 2H, CH2);
2.12 (s, 3H, S–CH3). IR (KBr (cmꢀ1)): 3268; 1744;
1625; 1533. MS (m/z/rel. int.): 375 (M+)/69; 213/100;
185/62; 129/37; 121/20; 56/25. Anal. Calc. for C17H21Fe-
NO3S (375.27): C, 54.41; H, 5.64; N, 3.73. Found: C,
54.22; H, 5.82; N, 3.61%. Yield: 75%.
3. Conclusion
N-Ferrocenoyl amino acid esters can be produced in
high yields via palladium-catalysed aminocarbonylation
starting from iodoferrocene and amino acid methyl es-
ters. The use of an excess of DBU favours the formation
of the a-ketoamides, and the corresponding N-ferroce-
nylglyoxyl amino acid esters can be obtained with mod-
erate to good selectivity. In the latter reactions, the
formation of two new ferrocene derivatives, obtained
by the acylation of DBU by the acyl-palladium interme-
diate, can also be observed.
4.1.2. N-Ferrocenoyl-L-proline methyl ester (3e)
1H NMR(CDCl3) d: 4.85 (brs, 1H, Cp-2); 4.69 (brs,
1H, Cp-5); 4.61 (brs, 1H, CHCOO); 4.34 (brs, 2H, Cp-
3,4); 4.25 (s, 5H, Cp); 3.94 (m, 1H, NCHa); 3.81 (m,
1H, NCHb); 3.76 (s, 3H, OCH3); 2.2 (m, 2H, CH2);
1.98 (m, 2H, CH2).13C NMR(CDCl3) d:173.0; 169.6;
71.3; 70.5; 70.2; 69.7; 60.1; 52.1; 48.3; 28.7; 25.6. IR
(KBr (cmꢀ1)): 1740; 1590. MS (m/z/rel. int.): 341 (M+)/
79; 213/100; 185/45; 129/45; 121/47; 56/25. Anal. Calc.
for C17H19FeNO3 (341.19): C, 59.85; H, 5.61; N, 4.11.
Found: C, 60.02; H, 5.50.; N, 4.23%. Yield: 84%.
4. Experimental
1
The H and 13C NMR spectra were recorded on a
VARIAN INOVA 400 spectrometer at 400 and
100.58 MHz, respectively. GLC analyses were carried
out with a HP-5890/II gas chromatograph using a
15 m HP-5 column. Infrared (IR) spectra were recorded
in KBr pellets using a Specord-IR 75 instrument. GC-
MS measurements were performed with a Hewlett–
Packard 5971A GC-MSD using HP-1 column.
4.1.3. N-Ferrocenylglyoxyl-glycine methyl ester (4a)
1H NMR(CDCl3) d: 7.64 (brs, 1H, NH); 5.31 (s, 2H,
Cp-2,5); 4.71 (s, 2H, Cp-3,4); 4.24 (s, 5H, Cp); 4.14 (d,
5.6 Hz, 2H, CH2); 3.79 (s, 3H, OCH3). 13C
NMR(CDCl3) d: 189.7; 169.5; 161.8; 74.5; 74.4; 74.3;
72.2; 70.6; 69.9; 52.5; 40.9 IR (KBr (cmꢀ1)): 3430;
1740; 1680; 1650 MS (m/z/rel. int.): 329 (M+)/79; 213/
100; 185/82; 129/74; 121/47; 56/53. Anal. Calc. for
C15H15FeNO4 (329.14): C, 54.74; H, 4.59; N, 4.26.
Found: C, 54.92; H, 4.71; N, 4.17%. Yield: 89%.
4.1. Carbonylation of iodoferrocene (1)
Iodoferrocene (0.5 mmol), Pd(OAc)2 (0.025 mmol),
PPh3 (0.05 mmol), the hydrochloride of the amino acid
ester (2.5 mmol), Et3N or DBU (as indicated in Tables
1 and 2) and THF (12.5 mL) were transferred under
an inert atmosphere into a stainless steel autoclave. It
was charged with carbon monoxide and heated with stir-
ring in an oil bath.
4.1.4. N-Ferrocenylglyoxyl-L-alanine methyl ester (4b)
1H NMR(CDCl3) d: 7.61 (d, 8 Hz, 1H, NH); 5.35
(brs; 1H, Cp-2); 5.25 (brs, 1H, Cp-5); 4.70 (brs, 2H,

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A. Kuik et al. / Journal of Organometallic Chemistry 690 (2005) 3237–3242
3241
Cp-3,4); 4.63 (quint., 8 Hz, 1H, CH); 4.22 (s, 5H, Cp);
3.78 (s, 3H, OCH3); 1.51 (d, 8 Hz, 3H, –CH–CH3).
13C NMR(CDCl3) d: 189.9; 172.5; 161.2; 74.5; 74.4;
74.3; 72.5; 71.8; 70.6; 52.6; 48.0; 18.0. IR (KBr
(cmꢀ1)): 3320, 1748; 1683; 1650. MS (m/z/rel. int.): 343
(M+)/66; 213/100; 185/49; 129/41; 121/22; 56/13. Anal.
Calc. for C16H17FeNO4 (343.16): C, 56.00; H, 4.99;
N,4.08. Found: C, 56.17; H, 5.12; N, 4.17%. Yield: 28%.
(cmꢀ1)): 1650; 1638. MS: 382 (M+). Anal. Calc. for
C20H26FeN2O2 (382.29): C, 62.84; H, 6.86; N, 7.33.
Found: C, 62.97; H, 6.71; N, 7.41%.
4.1.9. 1-Ferrocenylglyoxyl-1,8-diaza-cycloundecan-2-one
(8b)
1H NMR (CDCl3) d: 8.00 (brs, 1H, NH); 5.29 (brs;
2H, Cp-2,5); 4.65 (brs, 2H, Cp-3,4); 4.20 (s, 5H, Cp);
3.47 (m, 2H, C(O)NCH2); 3.34 (m, 4H, CH2NCH2);
2.55 (m, 2H, C(O)CH2); 1.68 (m, 8H, 4CH2). 13C
NMR(CDCl3) d: 190.9; 176.5; 162.1; 74.8; 74.0; 72.1;
70.4; 49.7; 45.5; 37.2; 36.0; 30.0; 28.6; 27.8; 23.4. IR
(KBr (cmꢀ1)):. 1700; 1646; 1634. MS: 410 (M+). Anal.
Calc. for C21H26FeN2O3 (410.30): C, 61.48; H, 6.39;
N, 6.83. Found: C, 61.32; H, 6.51; N, 6.75%.
4.1.5. N-Ferrocenylglyoxyl-L-phenylalanine methyl ester
(4c)
1H NMR(CDCl3) d: 7.24 (m, 5H, Ph); 6.50 (brs, 1H,
NH); 5.25 (brs, 2H, Cp-2,5); 4.90 (m, 1H, CH); 4.68
(brs, 2H, Cp-3,4); 4.14 (s, 5H, Cp); 3.74 (s, 3H,
OCH3); 3.18 (m, 2H, CHaHb). 13C NMR(CDCl3) d:
189.7; 171.2; 161.1; 135.7; 129.2; 128.8; 127.3; 74.4;
74.3; 72.2; 72.1; 70.5; 53.1; 52.5; 38.0. IR (KBr
(cmꢀ1)): 3360, 1736; 1683; 1642. MS (m/z/rel. int.): 419
(M+)/35; 213/71; 185/62; 129/70; 121/45; 91/100; 56/26.
Anal. Calc. for C22H21FeNO4 (419.26): C, 63.03; H,
5.05; N, 3.34. Found: C, 62.91; H, 5.14; N, 3.22%. Yield:
26%.
Acknowledgements
The authors thank the Hungarian National Science
Foundation (OTKA TS044742, T048391).
4.1.6. N-Ferrocenylglyoxyl-L-methionine methyl ester
(4d)
References
1H NMR(CDCl3) d: 7.73 (d, 8 Hz, 1H, NH); 5.34 (s,
1H, Cp-2); 5.26 (s, 1H, Cp-5); 4.76 (m, 1H, CH); 4.71
(brs, 2H, Cp-3,4); 4.22 (s, 5H, Cp); 3.78 (s, 3H,
OCH3); 2.57 (t, 8 Hz, S–CH2); 2.29–2.0 (m, 2H, CH2);
2.11 (s, 3H, S–CH3). 13C NMR(CDCl3) d: 189.7;
171.5; 161.4; 74.6; 74.5; 74.4; 72.5; 71.9; 70.6; 52.7;
51.4; 31.5; 30.1; 15.5. IR (KBr (cmꢀ1)): 3360; 1740;
1683; 1642. MS (m/z/rel. int.): 403 (M+)/85; 213/100;
185/53; 129/48; 121/24; 56/13. Anal. Calc. for C17H21Fe-
NO3S (403.28): C, 53.61; H, 5.25; N, 3.47. Found: C,
53.84; H, 5.11; N, 3.59%. Yield: 37%.
[1] S. Zhang, G. Wright, Y. Yang, Biosens. Bioelectron. 15 (2000)
273.
[2] S.J. Dong, B.Q. Wang, Electroanalysis 14 (2002) 7.
[3] J. Shah, E. Wilkins, Electroanalysis 15 (2003) 157.
[4] A.J. Baeumner, Anal. Bioanal. Chem. 377 (2003) 434.
[5] P.D. Beer, P.V. Bernhardt, J. Chem. Soc., Dalton Trans. (2001)
1428.
[6] P.D. Beer, E.J. Hayes, Coord. Chem. Rev. 240 (2003) 167.
[7] C.J. Yu, Y.J. Wan, H. Yowanto, J. Li, C.L. Tao, M.D. James,
C.L. Tan, G.F. Blackburn, T.J. Meade, J. Am. Chem. Soc. 123
(2001) 11155.
[8] M. Nakayama, T. Ihara, K. Nakano, M. Maeda, Talanta 56
(2002) 857.
[9] A.E. Navarro, N. Spinelli, C. Chaix, C. Moustrou, B. Mandrand,
H. Brisset, Bioorg. Med. Chem. Lett. 14 (2004) 2439.
[10] Y. Degani, A. Heller, J. Am. Chem. Soc. 110 (1988) 2615.
[11] H.B. Kraatz, J. Lusztyk, G.D. Enright, Inorg. Chem. 36 (1997)
2400.
4.1.7. N-Ferrocenylglyoxyl-L-proline methyl ester (4e)
1H NMR(CDCl3) d: 5.01 (brs, 2H, Cp-2,5); 4.73 (brs,
1H, CHCOO); 4.62 (brs, 2H, Cp-3,4); 4.3 (s, 5H, Cp);
3.8 (s, 3H, OCH3); 3.65 (m, 2H, N–CH2); 1.9-2.3 (m,
4H, CH2-CH2). 13C NMR(CDCl3) d: 189.2; 172.1;
164.5; 74.9; 73.8; 73.7; 70.6; 70.5; 70.4; 58.5; 52.4; 47.6;
29.0; 25.0. IR (KBr (cmꢀ1)): 1744; 1665; 1634. MS (m/
z/rel. int.): 369 (M+)/43; 213/100; 185/49; 129/39; 121/
26; 56/22. Anal. Calc. for C18H19FeNO4 (369.20): C,
58.56; H, 5.19; N, 3.79. Found: C, 58.41; H, 5.23; N,
3.87%. Yield: 30%.
[12] H.B. Kraatz, D.M. Leek, A. Houmam, G.D. Enright, J. Lusztyk,
D.D.M. Wayner, J. Organomet. Chem. 589 (1999) 38.
[13] P. Saweczko, H.B. Kraatz, Coord. Chem. Rev. 190–192 (1999)
185.
[14] J.F. Gallagher, P.T.M. Kenny, Inorg. Chem. Commun. 2 (1999)
200.
[15] H.S. Mandal, H.B. Kraatz, J. Organomet. Chem. 674 (2003) 32.
[16] W. Bauer, K. Polborn, W. Beck, J. Organomet. Chem. 579 (1999)
269.
[17] D.G. McCafferty, B.M. Bishop, C.G. Wall, S.G. Hughes, S.L.
Mecklenberg, T.J. Meyer, B. Erickson, Tetrahedron 51 (1995)
1093.
4.1.8. 1-Ferrocenoyl-1,8-diaza-cycloundecan-2-one (8a)
1H NMR(CDCl3) d: 7.38 (brs, 1H, NH); 4.80 (brs;
2H, Cp-2,5); 4.29 (brs, 2H, Cp-3,4); 4.19 (s, 5H, Cp);
3.54 (m, 2H, C(O)NCH2); 3.34 (m, 4H, CH2NCH2);
2.59 (m, 2H, C(O)CH2); 1.72 (m, 8H, 4CH2). 13C
NMR(CDCl3) d: 177.3; 170.2; 70.3; 70.2; 69.7; 68.3;
49.5; 44.7; 37.2; 34.7; 30.0; 28.4; 27.3; 23.5. IR (KBr
[18] T. Moriuchi, A. Nomoto, Y. Kazuhiro, A. Ogawa, T. Hirao,
J. Am. Chem. Soc. 123 (2001) 68.
[19] W.F.R. Jackson, D. Turner, H.M. Block, Synlett 6 (1996) 862.
[20] S.A. Carlstro¨m, T. Frejd, J. Org. Chem. 55 (1990) 4175.
[21] M. Beller, B. Cornils, C.D. Frohning, C.W. Kohlpaintner,
J. Mol. Catal. A 104 (1995) 17.
´
[22] R. Skoda-Fo¨ldes, L. Kollar, Curr. Org. Chem. 6 (2002) 1097.

´
A. Kuik et al. / Journal of Organometallic Chemistry 690 (2005) 3237–3242
3242
[23] M. Beller, in: W.A. Herrmann, B. Cornils (Eds.), Applied
Homogeneous Catalysis, Wiley–VCH, New York, 2003, pp.
148–158.
[29] M. Watanabe, S. Araki, Y. Butsugan, J. Org. Chem. 56 (1991)
2218.
[30] N. Tsukada, Y. Ohba, Y. Inoue, J. Organomet. Chem. 687 (2003)
436.
ˇ
[31] W.-C. Shieh, S. Dell, O. Repic, J. Org. Chem. 67 (2002) 2188.
´ ´
[24] E. Mu¨ller, G. Peczely, R. Skoda-Fo¨ldes, E. Takacs, G. Kokotos,
´
E. Bellis, L. Kollar, Tetrahedron 61 (2005) 797.
´
[25] Z. Szarka, R. Skoda-Fo¨ldes, L. Kollar, Tetrahedron Lett. 42
(2001) 739.
[26] Z. Szarka, R. Skoda-Fo¨ldes, A. Kuik, Z. Berente, L. Kolla´r,
ˇ
[32] W.-C. Shieh, M. Lozanov, M. Loo, O. Repic, T.J. Blacklock,
Tetrahedron Lett. 44 (2003) 4563.
´
[33] T.R. Juneja, D.K. Garg, W. Scha¨fer, Tetrahedron 38 (1982)
551.
Synthesis (2003) 545.
´
´
[27] A. Kuik, Z. Szarka, R. Skoda-Fo¨ldes, L. Kollar, Lett. Org.
Chem. 1 (2004) 151.
[34] Y. Wang, D.P. Rillema, Inorg. Chem. Commun. 1 (1998) 27.
[35] M.J. Sheehy, J.F. Gallagher, M. Yamashita, Y. Ida, J. White-
Colangelo, J. Johnson, R. Orlando, P.T.M. Kenny, J. Organomet.
Chem. 689 (2004) 1511.
´
[28] Z. Szarka, A. Kuik, R. Skoda-Fo¨ldes, L. Kollar, J. Organomet.
´
Chem. 689 (2004) 2770.