The chemistry of metallacyclic alkenylcarbene complexes: Part 9. Synthesis and reactions of chelated η2-alkene- and η3-allyl-carbene complexes of cobalt, manganese and chromium

Article abstract of DOI:10.1016/S0022-328X(99)00203-X

Cobaltalactams 7 with alkyl substituents at the nitrogen atom are accessible by UV-irradiation of CpCo(CO)₂ 6 in the presence of the appropriate vicinal aminoalkenol 8. Thus chelated (η³-allyl)cobaltcarbene complexes with either (endo-amino)oxo (3), (exo-amino)oxo (11), or dioxo (2) substitution at the carbene carbon atom are now available. A synthetic route to chelated (η²-alkene)-carbene complexes of chromium with allylically situated hydroxy groups is also presented.

Full text of DOI:10.1016/S0022-328X(99)00203-X

www.elsevier.nl/locate/jorganchem
Journal of Organometallic Chemistry 585 (1999) 115–126
The chemistry of metallacyclic alkenylcarbene complexes
Part 9. Synthesis and reactions of chelated h2-alkene- and
h3-allyl-carbene complexes of cobalt, manganese and chromiumꢀ
Sven-Eric Eigemann, Rainer Schobert *
School of Chemistry, Queen’s Uni6ersity of Belfast, Belfast BT9 5AG, UK
Received 12 February 1999; received in revised form 8 April 1999
Abstract
Cobaltalactams 7 with alkyl substituents at the nitrogen atom are accessible by UV-irradiation of CpCo(CO)2 6 in the presence
of the appropriate vicinal aminoalkenol 8. Thus chelated (h3-allyl)cobaltcarbene complexes with either (endo-amino)oxo (3),
(exo-amino)oxo (11), or dioxo (2) substitution at the carbene carbon atom are now available. A synthetic route to chelated
(h2-alkene)-carbene complexes of chromium with allylically situated hydroxy groups is also presented. © 1999 Elsevier Science
S.A. All rights reserved.
Keywords: Carbene complexes; Metallacycles; Co; Cr; Mn
2. Results and discussion
1. Introduction
Complexes 2 and 3 are isoelectronic to the iron
analogues 1 but were expected to show different reac-
tivities. For systematic studies on their chemistry we
prepared an array of derivatives of them. Analogous
complexes of chromium 4 and manganese 5 are un-
known, so far (Fig. 1).
The first notes on the preparation of cobaltalac-
tones and -lactams were published by Aumann et al.,
although without providing detailed experimental data
[3]. Their synthesis of cobaltalactams from vinyl
aziridines and (h5-cyclopentadienyl)dicarbonylcobalt
(6) seemed to be restricted to derivatives bearing elec-
Over the last years we have reported reactions of
different types of chelated (h3-allyl)-ironcarbene com-
plexes 1 with a variety of nucleophiles. We also ex-
amined the influence of the nature of the nucleophile,
of the substituents at the carbene carbon atom and at
the organic periphery on the course and selectivity of
such reactions, especially those proceeding with C–C
bond formation [2]. In the current paper we report
on new variations regarding the central metal frag-
ment, on a versatile synthesis of cobaltalactams bear-
ing alkyl substituents at the nitrogen atom, and on
the effect of donor groups like OH in the vicinity of
potential p-ligating CꢀC bonds tethered to the car-
bene carbon atom.
ꢀ For Part 8, see Ref. [1].
* Corresponding author.
E-mail address: r.schobert@queens-belfast.ac.uk (R. Schobert)
Fig. 1. h3-Allyl carbene complexes.
0022-328X/99/$ - see front matter © 1999 Elsevier Science S.A. All rights reserved.
PII: S0022-328X(99)00203-X

116
S.-E. Eigemann, R. Schobert / Journal of Organometallic Chemistry 585 (1999) 115–126
Table 1
Preparation of aminooxocobaltcarbene complexes 11 by aminolysis
reaction
Amine
R1
R2
Product Yield (%)
Methylamine
Benzylamine
Allylamine
(−)-Myrthanyl-
amine
CH3
H
H
H
H
11a
11b
11c
11d
98
68
64
17
CH2Ph
CH2CHCH2
C10H17
Glycine
methylester
b-Alanine
methylester
Amino-
CH2COOCH3
H
H
H
11e
11f
11g
87
79
91
CH2CH2COOCH3
CH2CH(OCH3)2
Scheme 1.
acetaldehyde
dimethylacetal
Aminoacetonitrile CH2CN
Dimethylamine CH3
tron-withdrawing groups at the nitrogen atom. We
have now opened access to cobaltalactams 7 with alkyl
substituents on the ring nitrogen atom by UV-irradia-
tion of 6 in the presence of 1-amino-3-buten-2-ols 8. We
also optimised our previous protocol [4a] for the syn-
thesis of cobaltalactone 9 from isoprene oxide 10 and 6
[4b]. The corresponding carbene complexes 2a and 3a/b
are readily available by subsequent alkylation of 7 and
9 with Meerwein salt (Scheme 1).
H
11h
81
32
CH3 11i
groups in the allylic position. Hitherto, little was known
about the effect of such groups on the coordination
tendency of the adjacent p-ligand. Neither manganese
nor chromium form any stable oxo-substituted (h2-
alkene)carbene complexes (X=O) at all [5]. Aza-substi-
tuted (h2-alkene)carbene complexes (X=NR%) had
been synthesised by Hegedus et al. (Cr) [6], Rudler et
al. (Cr, W) [7] and Templeton et al. (Mn) [8] but were
lacking allylic groups amenable to cleavage. We pre-
pared the aminocarbene complexes 12 and 13 starting
from 4-methylamino-2-buten-1-ol 14, with the intention
of removing their hydroxy groups as water by treat-
ment with tetrafluoroboric acid after coordination of
the double bond. The chromium complexes 12 are
available by a normal aminolysis reaction [9–11] of 14
and the respective methoxycarbene complexes 15.
Whereas p-coordination of unsaturated ligands like
olefins and acetylenes, including tethered ones, to
chromiumcarbene complexes is quite often achieved by
thermically induced substitution [12,13] of other ancil-
lary ligands like carbon monoxide, warming of 12 only
leads to its decomposition. However, the alkenechromi-
umcarbene complexes 16 can be obtained in excellent
yields by irradiation of 12 at −30°C. They form yel-
low–red oils stable at r.t. (Scheme 3)
Whereas the iron complexes 1 mostly react with
nucleophiles at their allyl ligand [2], the cobalt ana-
logues 2 and 3 behave more like typical Fischer carbene
systems. With primary amines in acetonitrile at room
temperature (r.t.) complex 2a, for instance, undergoes
aminolysis to give the (exo-amino)oxo-substituted car-
bene complexes 11 [4a].
a-Amino esters also give rise to the corresponding
derivatives of 11 in good yields upon reaction with 2a
at −20°C in dichloromethane (Scheme 2). Secondary
amines are either inert (at −20°C) or merely lead to
demethylation to give 9 (at r.t.), with the sole exception
of dimethylamine which reacts with 2a to leave the
corresponding carbene complex 11i upon chromato-
graphic workup. Table 1 shows some derivatives of 11
prepared by this carefully optimised aminolysis reac-
tion. As expected, the (endo-amino)oxocarbene com-
plexes 3 do not react with any types of amines at all,
presumably due to a more effective stereoelectronic
shielding of their carbene carbon atoms by the ring
nitrogen atom and its substituent.
Similar (h3-allyl)complexes of chromium 4 and man-
ganese 5 should in principle be accessible via the corre-
sponding h2-alkene precursors bearing suitable leaving
Scheme 2.
Scheme 3.

S.-E. Eigemann, R. Schobert / Journal of Organometallic Chemistry 585 (1999) 115–126
117
use. The starting complexes 15 [17] and 17 [18] were
prepared as published; the a-aminoesters and
aminoacetonitriles were freshly prepared from their re-
spective, commercially available hydrochlorides prior to
use (see the following procedure). Melting points are
uncorrected and boiling points quoted for Kugelrohr
distillations refer to the temperature of the air bath. IR:
Beckmann Acculab A1, A3 A8; Perkin–Elmer 1420.
NMR: Jeol JNM PMX 60, JNM-PS 100 and GNM
GX 400 FT; TMS as internal standard. MS: Varian
MAT-CH-4B (EFO-4B-source; 70 eV). MA: Heraeus
Mikromat C-H-N. hw: Hanau TQ 150 mercury vapour
lamp.
Scheme 4.
3.2. (p5-Cyclopentadienyl)-[(4-6-p3)-4-methyl-2-oxa-1-
oxo-4-hexen-1,6-diyl]-cobalt(III) (9) [3,4]
The manganese complex 13 is accessible by addition
of the amino group of 14 onto the carbyne complex 17
[14,15]. Interestingly, irradiation of 13 even at low
temperature leads to decomposition, whereas the corre-
sponding (p-alkene)carbene complex 18 lacking a termi-
nal hydroxy group can be easily prepared in this way
from the allylamino substituted carbene complex 19. It
is obviously the OH group itself that prevents ligation
of the adjacent olefin moiety from yet unknown rea-
sons. As moderately electron-withdrawing substituents,
such as allylically situated alkoxy and ester groups, are
known [16] to activate the alkene toward metal coordi-
nation due to an enhanced d–p* back-bonding compo-
nent, electronic reasons are unlikely to be responsible
here, even more so as the Cp(CO)Mn-fragment should
bear more electron density than the (OC)4Cr-core. Ei-
ther the respective Mn-analogues of 16 are too sensitive
to survive the conditions of their preparation for long
enough a time, or the hydroxy group enables formation
of Mn–O-chelate complexes which then undergo rapid
decomposition to give products of higher oxidation
states than the rather uncommon Mn(I) in 13 and 18
(Scheme 4).
An irradiation apparatus was set up consisting of a
mercury pressure lamp, a double-jacketed reaction ves-
sel (suitable for water-cooling the reaction mixture both
at the wall separating it from the centrally mounted
mercury vapour lamp and at the outer wall) equipped
with a nitrogen inlet and a water-cooled reflux con-
denser topped by a mercury valve or a septa/balloon
combination. The reaction vessel was flushed with dry
nitrogen and then charged with CpCo(CO)2 6 (12.01 g
of 85% material, 56.70 mmol), isoprene oxide 10 (5.61
g, 66.71 mmol) and benzene (100 ml). The mixture was
irradiated for 3 h maintaining a temperature of ca.
40°C within the solution by a slight stream of cooling
water in the vessel jackets. The reflux condenser was
operated at its maximum performance to prevent any
loss of the volatile oxirane 10. The progress of the
reaction was monitored by TLC (silica gel, diethyl
ether). Once the reaction had come to a halt, another
1.00 ml (0.86 g, 10.26 mmol) of isoprene oxide 10 was
added and irradiation continued for a further hour. The
lamp was finally switched off, the entire set-up was
dismantled and all volatile components were removed
in vacuo. The residue thus obtained was then purified
by column chromatography. Eluting first with diethyl
ether removed any impurities and residual starting ma-
terials. The pure product 9 could be washed off the
column with 1:1 acetonitrile–dichloromethane. After
concentration of the eluate on a rotary evaporator and
drying on an oil pump 6.20 g (48%) of 9 was obtained
as orange crystals of m.p. 137°C (dec.); Rf (Et2O)=
0.17, Rf (1:1 CH3CN–CH2Cl2)=0.50. 1H-NMR
(CDCl3): l=1.44 [dd, 2J(6-Hexo/6-Hendo)=2.50 Hz,
3J(5-H/6-Hendo)=11.96 Hz, 1H, 6-Hendo], 1.86 [s, 3H,
Attempts to cleave the OH-group in 16 with te-
trafluoroboric acid failed and only led to decomposi-
tion. We are currently testing other acids and also
different leaving groups like tosylate as well as different
combinations of leaving groups/cleavage reagents like
halide/silver tetrafluoroborate to complete the synthesis
of 4.
3. Experimental
3.1. General information
2
4-CH3], 3.10 [d, J(3-Hexo/3-Hendo)=10.99 Hz, 1H, 3-
2
Hendo], 3.57 [d, J(3-Hendo/3-Hexo)=10.99 Hz, 1H, 3-
All reactions were carried out under an atmosphere
of argon. All solvents were dried according to literature
procedures and freshly distilled under argon prior to
Hexo], 3.66 [dd, 2J(6-Hendo/6-Hexo)=2.50 Hz,
3J(5-H/6-Hexo)=4.10 Hz, 1H, 6-Hexo], 5.02 [s, 5H, Cp],

118
S.-E. Eigemann, R. Schobert / Journal of Organometallic Chemistry 585 (1999) 115–126
5.05 [mc, 1H, 5-H]. 13C-NMR (CDCl3): l=27.91 (4-
of the solution rose to ca. 50°C. After 12 h of refluxing
of the mixture, all volatile components were removed in
vacuo. The residue thus obtained was purified by
column chromatography with ethyl acetate on silica gel.
Me), 42.40 (6-C), 67.74 (3-C), 79.60 (5-C), 87.77 (Cp-
C), 88.48 (4-C), 203.61 (1-C). IR (KBr): w=3090 cm−1
,
2960, 2920, 2870, 1630, 1420, 1410, 1370, 1240, 1050,
980, 950, 830, 810, 610. MS (70 eV): m/z (%)=236 (70)
[M+], 208 (68) [M+ −CO, M+ −C2H4], 192 (37)
[M+ −C2H4O], 180 (80), 178 (90), 124 (100) [CoCp+],
98 (75), 59 (100), 39 (50), 28 (72) [CO+, C2H4+].
3.4.1. 1-Cyclohexylamino-2-methyl-3-buten-2-ol (8a)
Yield: 16.89 g (90%) from 30 g of cyclohexylamine as
a
colourless, strongly refractive liquid. 1H-NMR
(CDCl3): l=1.16 [mc, 6H, Hcyc], 1.21 [s, 3H, CH3],
1.71 [mc, 5H, Hcyc, N–H], 2.38 [mc, 1H, N–CHCC],
3.3. (p5-Cyclopentadienyl)-[(4-6-p3)-1-methoxy-4-meth-
yl-2-oxa-4-hexen-6-yl-1-ylidene] cobalt(III) tetrafluoro-
borate (2a)
2.47 [d, J(1-Ha/1-Hb)=11.47 Hz, 1H, 1-Ha], 2.69 [d,
2
2J(1-Ha/1-Hb)=11.47 Hz, 1H, 1-Hb], 5.05 [dd, 2J(4-
Hcis/4-Htrans)=1.77 Hz, J(3-H/4-Hcis)=10.74 Hz, 1H,
3
4-Hcis], 5.28 [dd, J(4-Hcis/4-Htrans)=1.77 Hz, J(3-H/4-
2
3
Under an atmosphere of dry nitrogen complex 9
(4.00 g, 16.94 mmol) was dissolved in dry
dichloromethane (50 ml). Trimethyloxonium te-
trafluoroborate (2.50 g, 16.94 mmol) was added at once
and the resulting mixture was stirred for ca. 3 h. Once
the reaction was completed (as to TLC-monitoring on
silica gel with 1:1 acetonitrile–dichloromethane, all
volatile components were removed in vacuo and the
remaining residue was finally purified by column chro-
matography. Any by-products and residual starting
materials were first washed off with neat diethyl ether,
the product complex 2a could then be eluted with 1:1
acetonitrile–dichloromethane and was obtained as a
yellow–olive solid upon drying on an oil pump. Yield:
4.34 g (76%), m.p. 114°C (dec.); Rf (1:1 CH3CN–
CH2Cl2)=0.45. 1H-NMR (CD3CN): l=1.78 [dd, 2J(6-
Htrans)=17.09 Hz, 1H, 4-Htrans], 5.80 [dd, 3J(3-H/4-
Hcis)=10.74 Hz, J(3-H/4-Htrans)=17.09 Hz, 1H, 3-H].
3
13C-NMR (CDCl3): l=25.05 (Ccyc), 25.87 (5-C), 26.16
(Ccyc), 33.87 (Ccyc), 55.92 (1-C), 56.82 (NCH), 71.29
(2-C), 112.76 (4-C), 144.06 (3-C). IR (NaCl): w=3470
cm−1, 3100, 2980, 2940, 2865, 1460, 1450, 1370, 1260,
1115, 1015, 920, 890, 795, 785, 745, 680, 670, 650.
3.4.2. 1-[(R)-Cyclohexylethylamino]-2-methyl-3-buten-
2-ol (8b)
Compound 8b is a mixture of two diastereomers
(ratio 1:0.68), which are indicated as 8b1 and 8b2. Yield:
20.73 g (96%) from 38.17 g of (R)-(−)-cyclohexylethy-
1
lamine as a colourless, strongly refractive liquid. H-
NMR (CDCl3): l=0.98 [mc, 5H, NCCH3, Hcyc], 1.23
[s, 3H, 2-CH3], 1.42 [mc, 8H, Hcyc], 2.57 [mc, 5H, 1-H,
CH3–CH, Hcyc, N–H], 5.08 [mc, 1H, 4-Hcis], 5.30 [mc,
1H, 4-Htrans], 5.80 [mc, 1H, 3-H]. 13C-NMR (CDCl3):
l=17.01 (NCMe1), 17.38 (NCMe2), 25.82 (5-Me2),
25.85 (5-Me1), 26.46 (Ccyc1), 26.58 (Ccyc2), 26.64 (Ccyc2),
26.71 (Ccyc1), 27.88 (Ccyc1), 28.52 (Ccyc2), 29.71 (Ccyc2),
29.86 (Ccyc1), 42.81 (Ccyc1), 43.12 (Ccyc2), 56.11 (1-C1),
56.27 (1-C2), 58.06 (NC1), 58.30 (NC2), 71.29 (2-Me1),
71.40 (2-Me2), 112.94 (4-C2), 113.02 (4-C1), 143.86 (3-
C). IR (NaCl): w=3430 cm−1, 3380, 3100, 2980, 2930,
2860, 1655, 1640, 1560, 1445, 1370, 1260, 1110, 1010,
985, 920, 880, 830, 780, 750, 670.
H
exo/6-Hendo)=2.75 Hz, 3J(5-H/6-Hendo)=12.10 Hz,
2
1H, 6-Hendo], 1.93 [s, 3H, 4-CH3], 3.95 [d, J(3-Hexo/3-
Hendo)=12.09 Hz, 1H, 3-Hendo], 4.04 [s, 3H, OCH3],
4.18 [dd, 2J(6-Hendo/6-Hexo)=2.75 Hz, 3J(5-H/6-
Hexo)=7.70 Hz, 1H, 6-Hexo], 4.40 [d, 2J(3-Hendo/3-
Hexo)=12.09 Hz, 1H, 3-Hexo], 5.36 [s, 5H, Cp], 5.52
[dd, J(6-Hendo/5-H)=12.10 Hz, J(6-Hexo/5-H)=7.70
Hz, 1H, 5-H]. 13C-NMR (CD3CN): l=27.38 (4-Me),
47.03 (6-C), 61.32 (OCH3), 79.05 (3-C), 85.20 (5-C),
90.24 (Cp-C), 93.14 (4-C), 245.86 (1-C). IR (KBr):
w=3095 cm−1, 2960, 2920, 2870, 1640, 1425, 1415,
1375, 1290, 1245, 1160–1020, 980, 950, 830, 810, 610.
MS (70 eV): m/z (%)=250 (100) [cation-H], 190 (39)
[cation-C2H4O2], 124 (72) [CoCp+], 95 (52), 67 (34), 59
(20) [Co+], 49 (24), 41 (31), 31 (26) [CH3O+], 28 (12)
[CO+]. Anal. Calc. for C12H16BCoF4O2 (338.0): C,
42.64; H, 4.77. Found: C, 42.53; H, 4.68%.
3
3
3.4.3. 1-Methylamino-2-methyl-3-buten-2-ol (8c)
(The solution was cooled to −20°C prior to addition
of methylamine). Yield: 7.40 g (63%) from 13.31 ml of
methylamine as a colourless, strongly refractive liquid.
1H-NMR (CDCl3): l=1.24 [s, 3H, 2-CH3], 2.42 [s, 3H,
2
NCH3], 2.49 [d, J(1-Ha/1-Hb)=11.48 Hz, 1H, 1-Ha],
3.4. Synthesis of aminoalkenols (8) [19]—general
procedure
2
2.63 [d, J(1-Ha/1-Hb)=11.48 Hz, 1H, 1-Hb], 5.07 [dd,
3
2J(4-Hcis/4-Htrans)=1.72 Hz, J(3-H/4-Hcis)=10.74 Hz,
2
3
1H, 4-Hcis], 5.28 [dd, J(4-Hcis/4-Htrans)=1.72 Hz, J(3-
To a mixture of the respective amine (300 mmol),
1.05 g (58.00 mmol) H2O and 0.50 g (5.80 mmol) conc.
HCl, isoprene oxide 10 (10.00 ml, 102.00 mmol) was
added dropwise over a period of 3 h. The temperature
H/4-Htrans)=17.34 Hz, 1H, 4-Htrans], 5.85 [dd, J(3-H/
3
4-Hcis)=10.74 Hz, 3J(3-H/4-Htrans)=17.34 Hz, 1H,
3-H]. 13C-NMR (CDCl3): l=26.27 (NMe), 37.09 (2-

S.-E. Eigemann, R. Schobert / Journal of Organometallic Chemistry 585 (1999) 115–126
119
[C3H5+], 30 (37) [H2CO+, C2H6+]. C19H28CoNO
(345.4): C 66.08, H 8.17, N 4.06; Found: C 66.15, H
8.26, N 4.12.
Me), 61.75 (1-C), 72.26 (2-C), 113.11 (4-C), 144.20
(3-C).
3.5. Photochemical synthesis of cobaltalactams 7 from 6
and 8—general procedure
1
3.5.2.1. Compound 7b1 (pure). H-NMR (CDCl3): l=
0.97 [d, 3J(NCH/NCCH3)=6.59 Hz, 3H, NCCH3],
1.30 [mc, 11H, Hcyc], 1.40 [dd, 1H, 2J(6-Hendo/6-Hexo)=
The irradiation apparatus described in the protocol
for the preparation of complex 9 was flushed with dry
nitrogen and then charged with CpCo(CO)2 6 (2.60 g,
14.44 mmol), amino alcohol 8 (10.00 mmol) and THF
(100 ml). The mercury lamp was switched on and the
entire mixture irradiated at 70°C (gentle reflux) for 3 h.
Then, all volatile components were removed in vacuo
and the remaining crude product was finally purified by
column chromatography (silica gel, neat diethyl ether).
2.19 Hz, J(5-H/6-Hendo)=12.65 Hz, 1H, 6-Hendo], 1.81
3
[s, 3H, 4-CH3], 2.32 [d, J(3-Hendo/3-Hexo)=11.72 Hz,
2
1H, 3-Hendo], 2.93 [d, 2J(3-Hendo/3-Hexo)=11.72 Hz,
1H, 3-Hexo], 3.53 [dd, 2J(6-Hendo/6-Hexo)=2.19 Hz,
3J(5-H/6-Hexo)=7.84 Hz, 1H, 6-Hexo], 3.77 [q,
3J(NCH/NCCH3)=6.59 Hz, 1H, NCH], 4.84 [mc, 1H,
5-H], 4.86 [s, 5H, Cp]. 1H-NMR (CD3CN): l=0.89
[dd, 2J(6-Hendo/6-Hexo)=1.10 Hz, 3J(5-H/6-Hendo)=
11.55 Hz, 1H, 6-Hendo], 1.29 [mc, 11H, Hcyc], 1.75 [d,
3J(NCH/NCCH3)=6.50 Hz, 3H, NCCH3], 1.97 [s, 3H,
3.5.1. (p5-Cyclopentadienyl)-[(4-6-p3)-2-aza-2-cyclohe-
xyl-4-methyl-1-oxo-4-hexen-1,6-diyl]-cobalt(III) (7a)
Yield: 980 mg (3.1 mmol, 31%) as an orange solid
from 1.85 g (10.09 mmol) 8a; Rf (Et2O)=0.43, Rf (1:1
CH3CN–CH2Cl2)=0.56. 1H-NMR (CDCl3): l=0.98
[dd, 2J(6-Hexo/6-Hendo)=1.80 Hz, 3J(5-H/6-Hendo)=
11.23 Hz, 1H, 6-Hendo], 1.42 [mc, 10H, Hcyc], 1.79 [s,
4-CH3], 2.33 [d, J(3-Hendo/3-Hexo)=11.00 Hz, 1H, 3-
2
Hendo], 2.87 [d, J(3-Hendo/3-Hexo)=11.00 Hz, 1H, 3-
2
Hexo], 3.49 [dd, 2J(6-Hendo/6-Hexo)=1.10 Hz,
3J(5-H/6-Hexo)=7.70 Hz, 1H, 6-Hexo], 3.70 [q,
3J(NCH/NCCH3)=6.50 Hz, 1H, NCH], 4.82 [s, 5H,
Cp], 4.94 [dd, 3J(5-H/6-Hendo)=11.55 Hz, 3J(5-H/6-
Hexo)=7.70 Hz, 1H, 5-H]. 13C-NMR (CDCl3): l=
15.71 (NCC), 25.82 (2 Ccyc), 23.73 (2 Ccyc), 30.09 (Ccyc),
30.26 (4-Me), 41.07 (NCCcyc), 41.86 (3-C), 48.38 (6-C),
51.83 (NCH), 78.58 (4-C), 79.53 (5-C), 87.64 (Cp-C),
199.00 (1-C).
2
3H, 4-CH3], 2.39 [d, J(3-Hexo/3-Hendo)=11.24 Hz, 1H,
3-Hendo], 2.91 [d, 2J(3-Hendo/3-Hexo)=11.24 Hz, 1H,
2
3
3-Hexo], 3.55 [dd, J(6-Hendo/6-Hexo)=1.80 Hz, J(5-H/
6-Hexo)=6.83 Hz, 1H, 6-Hexo], 3.87 [mc, 1H, NCHcyc],
4.87 [mc, 1H, 5-H], 4.88 [s, 5H, Cp]. 13C-NMR
(CDCl3): l=25.69 (2 Ccyc), 25.91 (Ccyc), 30.07 and
30.53 (Ccyc), 30.15 (4-Me), 42.68 (3-C), 48.05 (6-C),
51.17 (NCcyc), 77.88 (4-C), 79.55(5-C), 87.73 (Cp-C),
198.14 (1-C). IR (KBr): w=3070 cm−1, 2920, 2840,
1550, 1390, 1235, 1175, 1130, 930, 900, 810. MS (70
eV): m/z (%)=317 (100) [M+], 247 (20) [M+ −C5H10],
192 (37) [CoCpC5H8+], 124 (59) [CoCp+], 112 (57)
[CoC4H5+], 44 (34), 30 (42) [H2CO+, C2H6+]. Anal.
Calc. for C17H24CoNO (317.3): C, 64.35; H, 7.62; N,
4.41. Found: C, 64.12; H, 7.73; N, 4.52%.
1
3.5.2.2. Compound 7b2 (pure). H-NMR (CDCl3): l=
0.71 [d, 3J(NCH/NCCH3)=6.59 Hz, 3H, NCCH3],
1.25 [mc, 11 H, Hcyc], 1.30 [dd, 1H, 2J(6-Hendo/6-
Hexo)=2.20 Hz, 3J(5-H/6-Hendo)=12.65 Hz, 1H, 6-
Hendo],
1.79
[s,
3H,
4-CH3],
2.33
[d,
2J(3-Hendo/3-Hexo)=11.48 Hz, 1H, 3-Hendo], 2.72 [d,
2J(3-Hendo/3-Hexo)=11.48 Hz, 1H, 3-Hexo], 3.55 [dd,
2J(6-Hendo/6-Hexo)=2.20 Hz, J(5-H/6-Hexo)=8.06 Hz,
3
1H, 6-Hexo], 3.83 [q, J(NCH/NCCH3)=6.59 Hz, 1H,
3
NCH], 4.85 [mc, 1H, 5-H], 4.87 [s, 5H, Cp]. 13C-NMR
(CDCl3): l=15.80 (NCMe), 25.91 (2 Ccyc), 26.20 (2
Ccyc), 30.04 (Ccyc), 30.37 (4-Me), 39.70 (NCCcyc), 42.30
(3-C), 46.97 (6-C), 51.10 (NCH), 78.57 (4-C), 79.46
(5-C), 87.55 (Cp-C), 198.21 (1-C).
3.5.2. (p5-Cyclopentadienyl)-{(4-6-p3)-2-aza-2-[(R)-1%-
cyclohexylethyl]-4-methyl-1-oxo-4-hexen-1,6-diyl}-cob-
alt(III) (7b)
Yield: 955 mg (2.77 mmol, 30%) as an orange oil
from 2.05 g (9.70 mmol) 8b; mixture of diastereomers
indicated as 7b1 [Rf (Et2O)=0.76, Rf (1:1 CH3CN–
CH2Cl2)=0.51] and 7b2 [Rf (Et2O)=0.64, Rf (1:1
CH3CN–CH2Cl2)=0.49], which was separated by CC
(silica gel, neat diethyl ether). IR (NaCl/mixture): w=
3100 cm−1, 2990, 2940, 2870, 1580, 1570, 1480, 1455,
1410, 1380, 1265, 1200, 1180, 1150, 930, 860, 825, 740,
650. MS (70 eV): m/z (%)=345 (100) [M+], 275 (20)
[M+ −C5H10], 235 (21) [M+ −C8H14], 192 (37)
[CoCpC5H8+], 140 (57) [CoCpO+], 124 (54) [CoCp+],
111 (19) [CoC4H4+], 69 (49), 55 (33) [C3H5N+], 41 (26)
3.6. Synthesis of cobaltcarbene complexes 3a and 3b—
general procedure
Under an atmosphere of dry nitrogen complex 7 was
dissolved in dry dichloromethane (50–100 ml).
Trimethyloxonium tetrafluoroborate (1.2 to 1.5 equiva-
lents) was added at once and the resulting mixture was
stirred for ca. 5 h. Once the reaction was completed (as
to TLC monitoring on silica gel with 1:1 acetonitrile–
dichloromethane), all volatile components were re-

120
S.-E. Eigemann, R. Schobert / Journal of Organometallic Chemistry 585 (1999) 115–126
moved in vacuo and the remaining residue was finally
purified by column chromatography. Any by-products
and residual starting materials were first washed off
with neat diethyl ether, the product complex 3 could
then be eluted with 1:1 acetonitrile–dichloromethane
and was obtained as orange solid upon drying on an
oil pump.
from the respective diastereomerically pure starting
compounds 7b1 or 7b2 which could be readily obtained
by chromatographic separation of the mixture 7b.
3.6.2.1. Compound 3b1. 1H-NMR (CD3CN): l=1.04
[d, 3J(NCH/NCCH3)=6.60 Hz, 3H, NCCH3], 1.23
2
[mc, 6H, Hcyc], 1.40 [dd, J(6-Hendo/6-Hexo)=2.19 Hz,
3J(5-H/6-Hendo)=12.65 Hz, 1H, 6-Hendo], 1.63 [mc,
2
5H, Hcyc], 1.87 [s, 3H, 4-CH3], 2.99 [d, J(3-Hendo/3-
3.6.1. (p5-Cyclopentadienyl)-[(4-6-p3)-2-aza-2-cyclo-
hexyl-1-methoxy-4-methyl-4-hexen-6-yl-1-ylidene]-
cobalt(III) tetrafluoroborate (3a)
Hexo)=14.85 Hz, 1H, 3-Hendo], 3.54 [d, J(3-Hendo/3-
2
Hexo)=14.85 Hz, 1H, 3-Hexo], 3.75 [mc, 1H, NCH],
4.27 [dd, 2J(6-Hendo/6-Hexo)=2.19 Hz, 3J(5-H/6-
Hexo)=8.25 Hz, 1H, 6-Hexo], 4.29 [s, 3H, OCH3], 5.06
Yield: 50 mg (82%) from 60 mg (0.19 mmol) 7a and
42 mg (0.28 mmol) Me3OBF4; Rf (Et2O)=0.00, Rf
(1:1 CH3CN–CH2Cl2)=0.68. 1H-NMR (CD3CN):
l=1.24 [dd, 2J(6-Hexo/6-Hendo)=2.08 Hz, 3J(5-H/6-
Hendo)=12.33 Hz, 1H, 6-Hendo], 1.49 [mc, 10H, Hcyc],
3
3
[dd, J(5-H/6-Hendo)=12.65 Hz, J(5-H/6-Hexo)=8.25
Hz, 1H, 5-H], 5.27 [s, 5H, Cp]. 13C-NMR (CD3CN):
l=16.15 (NCCH3), 26.26 (Ccyc), 26.44 and 26.67
(Ccyc), 29.94 (4-Me), 30.48 and 30.66 (Ccyc), 41.18
(NCCcyc), 47.92 (6-C), 54.23 (3-C), 59.51 (NCH),
65.02 (OCH3), 83.81 (5-C), 84.68 (4-C), 88.58 (Cp-C),
225.31 (1-C).
2
1.87 [s, 3H, 4-CH3], 3.06 [d, J(3-Hexo/3-Hendo)=14.65
Hz, 1H, 3-Hendo], 3.54 [d, 2J(3-Hendo/3-Hexo)=14.65
2
Hz, 1H, 3-Hexo], 3.91 [mc, 1H, NCH], 4.27 [dd, J(6-
3
H
endo/6-Hexo)=2.08 Hz, J(5-H/6-Hexo)=8.42 Hz, 1H,
6-Hexo], 4.32 [s, 3H, OCH3], 5.09 [dd, 3J(5-H/6-
3.6.2.2. Compound 3b2. 1H-NMR (CD3CN): l=0.80
[d, 3J(NCH/NCCH3)=7.15 Hz, 3H, NCCH3], 1.12
Hendo)=12.33 Hz, J(5-H/6-Hexo)=8.42 Hz, 1H, 5-H],
3
5.28 [s, 5H, Cp]. 13C-NMR (CD3CN): l=25.80 (Ccyc),
26.07 (Ccyc), 29.82 (4-Me), 30.44 (Ccyc), 48.97 (6-C),
53.48 (3-C), 57.94 (NCcyc), 65.17 (OCH3), 83.72 (5-C),
84.12 (4-C), 88.56 (Cp-C), 224.43 (1-C). IR (KBr):
w=3060 cm−1, 2940, 2870, 1525, 1450, 1420, 1380,
1310, 1250, 1175, 1100–1000, 835, 800, 675. MS (70
eV): m/z (%)=332 (5) [cation], 304 (19) [cation-C2H4],
221 (22) [CoC11H16N+], 192 (49) [CoCpC5H8+], 124
(67) [CoCp+], 112 (54) [CoC4H5+], 86 (66) [C5H12N+],
70 (100) [C4H8N+, C5H1+0 ], 41 (32) [C3H5+], 30 (23)
[H2CO+, C2H6+]. Anal. Calc. for C18H27BCoF4NO
(419.2): C, 51.58; H, 6.49; N, 3.34. Found: C, 51.46;
H, 6.47; N, 3.29%.
[mc, 6H, Hcyc], 1.28 [dd, J(6-Hendo/6-Hexo)=2.20 Hz,
2
3J(5-H/6-Hendo)=12.65 Hz, 1H, 6-Hendo], 1.65 [mc,
2
5H, Hcyc], 1.87 [s, 3H, 4-CH3], 3.01 [d, J(3-Hendo/3-
2
Hexo)=14.84 Hz, 1H, 3-Hendo], 3.36 [d, J(3-Hendo/3-
Hexo)=14.84 Hz, 1H, 3-Hexo], 3.89 [mc, 1H, NCH],
4.26 [dd, 2J(6-Hendo/6-Hexo)=2.20 Hz, 3J(5-H/6-
Hexo)=8.25 Hz, 1H, 6-Hexo], 4.27 [s, 3H, OCH3], 5.10
3
3
[dd, J(5-H/6-Hendo)=12.65 Hz, J(5-H/6-Hexo)=8.25
Hz, 1H, 5-H], 5.28 [s, 5H, Cp]. 13C-NMR (CD3CN):
l=16.63 (NCCH3), 26.47 (Ccyc), 26.59 and 26.88
(Ccyc), 29.92 (4-Me), 30.48 and 30.66 (Ccyc), 39.78
(NCCcyc), 48.77 (6-C), 52.42 (3-C), 58.31 (NCH),
65.17 (OCH3), 83.83 (5-C), 84.09 (4-C), 88.52 (Cp-C),
225.23 (1-C).
3.6.2. (p5-Cyclopentadienyl)-{(4-6-p3)-2-aza-2-[(R)-1%-
cyclohexylethyl]-1-methoxy-4-methyl-4-hexen-6-yl-1-
ylidene}-cobalt(III) tetrafluoroborate (3b)
3.7. Aminolysis of 2a to gi6e 11—general procedure
Carbene
complex
2a
was
dissolved
in
Yield: 75 mg (76%) from 76 mg (0.22 mmol) of 7b
and 42 mg (0.28 mmol) Me3OBF4; inseparable mixture
of diastereomers 3b1 and 3b2 [Rf (1:1 CH3CN–
dichloromethane (50 ml mmol−1) which was then
chilled to −18°C. The respective amine was added at
once and the resulting mixture was allowed to stir for
a certain period of time (as indicated for each of the
following examples). The reaction mixture was finally
warmed up to ambient temperature, all volatile com-
ponents were evaporated on an oil pump and the
remaining residue was purified by column chromatog-
raphy. First, traces of the by-product 9 were washed
off with neat diethyl ether, then pure product complex
11 could be obtained by eluting with 1:1 acetonitrile–
dichloromethane, concentrating of the eluate and dry-
ing on an oil pump. Residual starting complex 2a
could be regained in some cases by continued elution
of the column with the same solvent mixture.
CH2Cl2)=0.80 for both]. IR (KBr): w=3080 cm−1
,
2990, 2940, 2870, 1530, 1470, 1455, 1415, 1380, 1310,
1255, 1200, 1180, 1150, 1100–1000, 825, 790, 675. MS
(70 eV): m/z (%)=360 (12) [M+ −BF4], 345 (19)
[M+ −CH3OBF4], 332 (19) [M+ −C2H4], 290 (42)
[M+ −C5H10BF4], 250 (67) [M+ −C8H14BF4], 192
(73) [CoCpC5H8+], 124 (100) [CoCp+], 112 (48)
[CoC4H5+], 70 (77) [C4H8N+, C5H1+0 ], 41 (41) [C3H5+],
30 (42) [H2CO+, C2H6+]. Anal. Calc. for
C20H31BCoF4NO (447.2): C, 53.72; H, 6.99; N, 3.13.
Found: C, 53.66; H, 6.86; N, 3.08%.
Pure samples of both 3b1 and 3b2 were prepared

S.-E. Eigemann, R. Schobert / Journal of Organometallic Chemistry 585 (1999) 115–126
121
3.7.1. (p5-Cyclopentadienyl)-[(4-6-p3)-1-methylamino-
4-methyl-2-oxa-4-hexen-6-yl-1-ylidene]-cobalt(III) tet-
rafluoroborate (11a)
1.95 Hz, 3J(5-H/6-Hendo)=12.20 Hz, 1H, 6-Hendo],
2
1.87 [s, 3H, 4-CH3], 3.76 [d, J(3-Hexo/3-Hendo)=11.96
Hz, 1H, 3-Hendo], 3.85 [mc, 2H, NCH2], 4.17 [mc, 2H,
3-Hexo, 6-Hexo], 5.16 [mc, 3H, 5-H, ꢀCH2], 5.27 [s, 5H,
Cp], 5.78 [mc, 1H, NCCH], 8.72 [s, 1H, NH]. 13C-
NMR (CD3CN): l=27.41 (4-Me), 47.16 (NCH2),
48.38 (6-C), 78.11 (3-C), 84.06 (5-C), 89.22 (Cp-C),
92.34 (4-C), 117.73 (ꢀCH2), 133.46 (NCC), 224.96 (1-
C). IR (NaCl): w=3360 cm−1, 3050, 2980, 1725, 1565,
1475–1410, 1380, 1340, 1260, 1130–1010, 905, 865.
MS (70 eV): m/z (%)=275 (36) [cation-H], 151 (29)
[CoCpCNH+], 124 (35) [CoCp+], 81 (30), 67 (25), 41
(100). Anal. Calc. for C14H19BCoF4NO (363.05): C,
49.65; H, 5.00; N, 3.86. Found: C, 49.76; H, 4.94; N,
3.92%.
Yield: 253 mg (98%) as a yellow–orange solid from
0.77 mmol of 2a and 1.00 ml (2.50 mmol) methy-
lamine; reaction time 1 h; Rf (1:1 CH3CN–CH2Cl2)=
0.75.
1H-NMR
(CD3CN):
l=1.50
[d,
3J(5-H/6-Hendo)=12.20 Hz, 1H, 6-Hendo], 1.86 [s, 3H,
3
4-CH3], 2.79 [d, J(N–H/N–CH3)=4.88 Hz, 3H, N–
CH3], 3.73 [d, 2J(3-Hexo/3-Hendo)=11.96 Hz, 1H, 3-
Hendo], 4.11 [d, J(5-H/6-Hexo)=9.04 Hz, 1H, 6-Hexo],
3
4.14 [d, 2J(3-Hendo/3-Hexo)=11.96 Hz, 1H, 3-Hexo],
5.25 [s, 5H, Cp], 5.27 [mc, 1H, 5-H], 8.61 [s, 1H,
N–H]. 13C-NMR (CD3CN): l=27.46 (4-Me), 31.20
(N–Me), 47.99 (6C), 77.94 (3-C), 84.09 (5-C), 89.13
(Cp-C), 92.32 (4-C), 225.36 (1-C). IR (KBr): w=3360
cm−1, 3090, 3030, 2960, 2920, 2900, 2820, 1720, 1570,
1460–1400, 1385, 1260, 1130–980, 835. MS (70 eV):
m/z (%)=249 (79) [cation-H], 183 (29) [cation-CpH2],
127 (60), 124 (33) [CoCp+], 108 (32), 70 (63), 58
(100), 55 (54), 49 (34), 41 (64), 28 (16) [CO+]. Anal.
Calc. for C12H17BCoF4NO (337.0): C, 42.77; H, 5.05;
N, 4.16. Found: C, 42.54; H, 4.78; N, 4.12%.
3.7.4. (p5-Cyclopentadienyl)-[(4-6-p3)-4-methyl-1-
(cis)-myrtanylamino-2-oxa-4-hexen-6-yl-1-ylidene]-co-
balt(III) tetrafluoroborate (11d)
Yield: 92 mg (17%) as an orange oil from 410 mg
(1.21 mmol) of 2a and 0.50 ml (3.00 mmol) (cis)-(−)-
myrtanylamine; reaction time 3 h; Rf (1:1 CH3CN–
CH2Cl2)=0.89. 11d was obtained as a mixture of two
diastereomers 11d1 and 11d2 (1:0.88), assignment of
the NMR signals to these isomers was possible by
integration in some cases. 1H-NMR (CD3CN): l=
0.95 [s, 3H, Me1], 0.97 [s, 3H, Me2], 1.14 [s, 3H, Me1],
3.7.2. (p5-Cyclopentadienyl)-[(4-6-p3)-1-benzylamino-4-
methyl-2-oxa-4-hexen-6-yl-1-ylidene] cobalt(III) tetra-
fluoroborate (11b)
1.20 [s, 3H, Me2], 1.47 [mc, 16 H, 6-Hendo, CHcyc
,
Yield: 227 mg (68%) as an orange oil from 269 mg
(0.80 mmol) of 2a and 128 mg (1.19 mmol) of benzy-
lamine; reaction time 3 h; Rf (1:1 CH3CN–CH2Cl2)=
CHc2yc], 1.87 [s, 3H, 4-Me1], 1.96 [s, 3H, 4-Me2], 3.20
[mc, 8H, NCH2, CHcyc], 3.74 [mc, 2H, 3-Hendo], 4.14
[mc, 4H, 3-Hexo, 6-Hexo], 5.25 [s, 5H, Cp1], 5.26 [s, 5H,
Cp2], 5.25 [mc, 2H, 5-H], 8.63 [s, 1H, NH]. 13C-NMR
(CD3CN): l=19.85 (Me1), 19.89 (Me2), 23.18 (Me1),
23.23 (Me2), 26.60 (H2C2), 27.40 (H2C1), 28.22 (4-
Me1), 28.30 (4-Me2), 33.66 (H2Ccyc1), 33.78 (H2Ccyc2),
39.32 (quart-C1), 39.36 (quart-C2), 41.39 (HCcyc1),
42.23 (HCcyc2), 44.18 (HCcyc1), 44.24 (HCcyc2), 48.16
(6-C2), 48.34 (6-C1), 50.33 (NCH22), 50.45 (NCH12),
77.75 (3-C1), 77.81 (3-C2), 83.95 (5-C1), 84.00 (5-C2),
89.15 (Cp2), 89.19 (Cp1), 92.19 (4-C1), 92.23 (4-C2),
225.14 (1-C). IR (NaCl): w=3350 cm−1, 3100, 3040,
2900, 1700, 1555, 1460–1410, 1370, 1340, 1255, 1100–
1000, 895, 840. MS (70 eV): m/z (%)=371 (100)
[cation-H], 249 (42) [cation-C9H14], 180 (27)
[CoCpC2H5NO+], 136 (33) [C8H10NO+, CoCpC+],
124 (73) [CoCp+], 114 (44), 93 (36), 81 (43), 69 (84)
[C4H5O+, C5H9+], 67 (53) [C5H7+], 55 (56), 49 (32), 41
(100), 30 (97) [C2H6+, H2CO+]. Anal. Calc. for
C21H31BCoF4NO (459.2): C, 54.92; H, 6.80; N, 3.05.
Found: C, 54.76; H, 6.74; N, 2.97%.
0.64.
1H-NMR
(CD3CN):
l=1.40
[dd,
2J(6-Hexo/6-Hendo)=2.18 Hz, 3J(5-H/6-Hendo)=12.10
Hz, 1H, 6-Hendo], 1.87 [s, 3H, 4-CH3], 3.75 [d, J(3-
2
H
exo/3-Hendo)=12.11 Hz, 1H, 3-Hendo], 4.15 [mc, 2H,
3-Hexo, 6-Hexo], 4.42 [mc, 2H, PhCH2], 5.26 [s, 5H,
Cp], 5.27 [mc, 1H, 5-H], 7.37 [mc, 5H, Ph], 9.02 [s,
1H, NH]. 13C-NMR (CD3CN): l=27.37 (4-Me),
48.39 (6-C), 68.39 (PhCH2), 78.10 (3-C), 84.04 (5-C),
89.23 (Cp-C), 92.30 (4-C), 128.71(m-Car), 128.72 (p-
Car), 129.52 (o-Car), 137.61 (ipso-Car), 226.51 (1-C). IR
(NaCl): w=3360 cm−1, 3050, 2980, 1720, 1555, 1495,
1470–1415, 1380, 1340, 1260, 1130–1010, 895, 845.
MS (70 eV): m/z (%)=325 (38) [cation-H], 260 (19)
[cation-CpH], 203 (39), 91 (100) [Bn+], 69 (42), 41
(30). Anal. Calc. for C18H21BCoF4NO (413.1): C,
52.55; H, 5.12; N, 3.39. Found: C, 52.32; H, 4.98; N,
3.43%.
3.7.3. (p5-Cyclopentadienyl)-[(4-6-p3)-1-allylamino-4-
methyl-2-oxa-4-hexen-6-yl-1-ylidene]-cobalt(III) tetra-
fluoroborate (11c)
3.7.5. (p5-Cyclopentadienyl)-[(4-6-p3)-1-(methoxycarb-
onylmethyl)amino-4-methyl-2-oxa-4-hexen-6-yl-1-ylid-
ene]-cobalt(III) tetrafluoroborate (11e)
Yield: 234 mg (87%) as an orange solid from 230
mg (0.70 mmol) of 2a and 0.50 ml (3.00 mmol) glycine
Yield: 487 mg (64%) as a brown oil from 680 mg
(2.09 mmol) of 2a and 0.24 ml (3.14 mmol) allylamine;
reaction time 3 h; Rf (1:1 CH3CN–CH2Cl2)=0.74.
2
1H-NMR (CD3CN): l=1.48 [dd, J(6-Hexo/6-Hendo)=

122
S.-E. Eigemann, R. Schobert / Journal of Organometallic Chemistry 585 (1999) 115–126
1
methylester; reaction time 3 h; Rf (1:1 CH3CN–
CH2Cl2)=0.67. 1H-NMR (CD3CN): l=1.64 [dd, 2J(6-
H
CH3CN–CH2Cl2)=0.65. H-NMR (CD3CN): l=1.48
[dd, 2J(6-Hexo/6-Hendo)=2.20 Hz, 3J(5-H/6-Hendo)=
12.09 Hz, 1H, 6-Hendo], 1.85 [s, 3H, 4-CH3], 3.28 and
3.29 [s each, 6H, OCH3, OCH3%], 3.30 [mc, 2H, NCH2],
3.74 [d, 2J(3-Hexo/3-Hendo)=12.09 Hz, 1H, 3-Hendo],
4.14 [mc, 2H, 3-Hexo, 6-Hexo], 4.42 [t, 3J(NCH2/
CH(OMe)2)=5.50 Hz, 1H, CH(OMe)2], 5.24 [mc, 1H,
5-H], 5.25 [s, 5H, Cp], 8.59 [s, 1H, NH]. 13C-NMR
(CD3CN): l=27.36 (4-Me), 46.17 (NCH2), 48.47 (6-C),
54.77 and 54.80 (OMe, OMe%), 78.05 (3-C), 84.90 (5-C),
89.24 (Cp-C), 92.20 (4-C), 102.45 (C(OMe)2), 227.42
(1-C). IR (NaCl): w=3350 cm−1, 3030, 2950, 2810,
1700, 1555, 1410, 1370, 1250, 1100–1000, 885, 840. MS
(70 eV): m/z (%)=323 (20) [cation-H], 291 (100) [cation-
CH5O], 279 (20) [cation-C2H5O], 250 (22) [cation-
C3H6O2], 230 (68), 191 (27), 180 (27) [CoCpC2H5NO+],
169 (100), 150 (100), 136 (88) [C8H10NO+, CoCpC+],
124 (100) [CoCp+], 108 (64), 100 (89) [CoC3H5+], 95
(83) [C6H8O+], 75 (100) [CoO+], 57 (99) [C3H5O+], 41
(98), 29 (63) [C2H5+, HCO+]. Anal. Calc. for
C15H23BCoF4NO3 (411.1): C, 43.83; H, 5.64; N, 3.40.
Found: C, 43.66; H, 5.52; N, 3.32%.
exo/6-Hendo)=2.20 Hz, 3J(5-H/6-Hendo)=12.10 Hz,
1H, 6-Hendo], 1.85 [s, 3H, 4-CH3], 3.66 [s, 3H, OCH3],
3.75 [s, 2J(3-Hexo/3-Hendo)=12.09 Hz, 1H, 3-Hendo], 3.97
[mc, 2H, NCH2], 4.15 [d, 2J(3-Hexo/3-Hendo)=12.09 Hz,
1H, 3-Hexo], 4.19 [dd, 2J(6-Hexo/6-Hendo)=2.20 Hz,
3J(5-H/6-Hexo)=8.25 Hz, 1H, 6-Hexo], 5.28 [mc, 1H,
5-H], 5.29 [s, 5H, Cp]. 13C-NMR (CD3CN): l=27.33
(4-Me), 45.33 (NCH2), 48.57 (6-C), 53.17 (OMe), 78.46
(3-C), 84.25 (5-C), 89.25 (Cp-C), 92.22 (4-C), 169.10
(CꢀO), 229.56 (1-C). IR (KBr): w=3520 cm−1, 3380,
3100, 2940, 1745, 1735, 1550, 1465, 1430, 1400, 1375,
1330, 1200, 1100–1000, 845. MS (70 eV): m/z (%)=308
(13) [cation], 307 (72) [cation-H], 185 (100) [cation-
CoC5H4], 149 (23), 124 (73) [CoCp+], 96 (55)
[C6H8O+], 88 (76) [C3H6NO2+], 70 (84) [C4H5O+,
C5H9+], 55 (58), 41 (85) [C3H5+], 30 (52) [C2H6+,
H2CO+]. Anal. Calc. for C14H19BCoF4NO3 (395.05): C,
41.11; H, 4.68; N, 3.42. Found: C, 40.96; H, 4.74; N,
3.37%.
3.7.6. (p5-Cyclopentadienyl)-[(4-6-p3)-1-(2%-methoxycar-
bonylethyl)amino-4-methyl-2-oxa-4-hexen-6-yl-1-ylid-
ene]-cobalt(III) tetrafluoroborate (11f)
3.7.8. (p5-Cyclopentadienyl)-[(4-6-p3)-1-cyanomethyl-
amino-4-methyl-2-oxa-4-hexen-6-yl-1-ylidene]-cobalt-
(III) tetrafluoroborate (11h)
Yield: 191 mg (79%) as an orange solid from 200 mg
(0.59 mmol) of 2a and 100 mg (0.97 mmol) b-alanine
methylester; reaction time 3 h; Rf (1:1 CH3CN–
CH2Cl2)=0.67. 1H-NMR (CD3CN): l=1.50 [dd, 2J(6-
Yield: 218 mg (81%) as a brown oil from 250 mg (0.74
mmol) of 2a and 140 mg (2.50 mmol) aminoacetonitrile;
reaction time 3 h; Rf (1:1 CH3CN–CH2Cl2)=0.74.
2
H
exo/6-Hendo)=2.20 Hz, 3J(5-H/6-Hendo)=12.10 Hz,
1H-NMR (CD3CN): l=1.52 [dd, J(6-Hexo/6-Hendo)=
1H, 6-Hendo], 1.89 [s, 3H, 4-CH3], 2.53 [t, 3J(NCH2/
NCCH2)=7.15 Hz, 2H, NCCH2], 3.45 [t, 3J(NCH2/
NCCH2)=7.15 Hz, 2H, NCH2], 3.65 [s, 3H, OCH3],
3.75 [d, 2J(3-Hexo/3-Hendo)=12.09 Hz, 1H, 3-Hendo],
4.15 [mc, 2H, 3-Hexo, 6-Hexo], 5.24 [s, 5H, Cp], 5.25 [mc,
1H, 5-H], 8.63 [s, 1H, NH]. 13C-NMR (CD3CN): l=
27.41 (4-Me), 33.82 (NCC), 40.67 (NC), 48.59 (6-C),
52.41 (OCH3), 78.12 (3-C), 84.12 (5-C), 89.20 (Cp-C),
92.30 (4-C), 172.47 (CꢀO), 226.66 (1-C). IR (KBr):
w=3350 cm−1, 3080, 2920, 1735, 1535, 1450, 1415,
1390, 1370, 1320, 1200, 1100–1000, 835, 720, 690. MS
(70 eV): m/z (%)=321 (13) [cation-H], 284 (88), 241 (92)
[cation-C6H10], 205 (52), 185 (33) [CoC8H14O+], 156
(100) [CoC5H7NO+, CoC6H9O+], 128 (99) [Cp2+], 108
(57), 100 (98) [CoC3H5+], 86 (96) [C4H6O2+, C3H4NO2+],
57 (100) [C3H5O+], 41 (92) [C3H5+], 28 (65) [CO+].
Anal. Calc. for C15H21BCoF4NO3 (409.1): C, 44.04; H,
5.17; N, 3.40. Found: C, 43.87; H, 5.02; N, 3.27%.
2.20 Hz, J(5-H/6-Hendo)=12.21 Hz, 1H, 6-Hendo], 1.88
3
2
[s, 3H, 4-CH3], 3.88 [d, J(3-Hexo/3-Hendo)=12.21 Hz,
2
1H, 3-Hendo], 4.15 [s, 2H, NCH2], 4.19 [dd, J(6-Hexo/6-
Hendo)=2.20 Hz, 3J(5-H/6-Hexo)=8.06 Hz, 1H, 6-Hexo],
4.28 [d, 2J(3-Hexo/3-Hendo)=12.21 Hz, 1H, 3-Hexo], 5.30
3
3
[s, 5H, Cp], 5.34 [dd, J(5-H/6-Hexo)=8.06 Hz, J(5-H/
6-Hendo)=12.21 Hz, 1H, 5-H], 8.95 [s, 1H, NH]. 13C-
NMR (CD3CN): l=27.34 (4-Me), 31.50 (NCH2), 48.58
(6-C), 79.19 (3-C), 84.56 (5-C), 89.51 (Cp-C), 92.80
(4-C), 115.76 (CN), 228.45 (1-C). IR (NaCl): w=3360
cm−1, 3110, 2960, 2070, 1660, 1540, 1470, 1430, 1410,
1380, 1330, 1250, 1190, 1160, 1110–970, 900, 850. MS
(70 eV): m/z (%)=274 (21) [cation-H], 180 (41)
[CoCpC2H5NO+], 152 (36) [CoCpCO+], 124 (100)
[CoCp+], 95 (43), 69 (70) [C4H5O+, C5H9+], 67 (43)
[C5H7+], 59 (35) [Co+], 41 (100), 28 (22) [C2H4+, CO+],
27 (24) [C2H3+, CHN+]. Anal. Calc. for
C13H16BCoF4N2O (362.0): C, 43.13; H, 4.46; N, 7.74.
Found: C, 42.96; H, 4.32; N, 7.57%.
3.7.7. (p5-Cyclopentadienyl)-[(4-6-p3)-1-(2%-dimethoxy-
methyl)amino-2-oxa-4-hexen-6-yl-1-ylidene]-cobalt(III)
tetrafluoroborate (11g)
Yield: 290 mg (91%) as an orange–brown oil from
262 mg (0.78 mmol) of 2a and 263 mg (2.50 mmol)
aminoethanal dimethylacetal; reaction time 2 h; Rf (1:1
3.7.9. (p5-Cyclopentadienyl)-[(4-6-p3)-1-dimethylamino-
4-methyl-2-oxa-4-hexen-6-yl-1-ylidene]-cobalt(III)
tetrafluoroborate (11i)
Yield: 141 mg (32%) as an orange solid from 410 mg
(1.21 mmol) of 2a and 0.50 ml (3.00 mmol) dimethyl-

S.-E. Eigemann, R. Schobert / Journal of Organometallic Chemistry 585 (1999) 115–126
123
amine; reaction time 5 h; Rf (1:1 CH3CN–CH2Cl2)=
0.67. 1H-NMR (CD3CN): l=1.47 [dd, 2J(6-Hexo/6-
Hendo)=2.44 Hz, 3J(5-H/6-Hendo)=12.45 Hz, 1H,
6-Hendo], 1.87 [s, 3H, 4-CH3], 2.96 and 3.57 [s each, 6H,
3.8.2. Pentacarbonyl-[(4Z)-2-aza-6-hydroxy-2-methyl--
1-phenyl-4-hexen-1-ylidene]-chromium(0) (12b)
Yield: 432 mg (42%) [beside 152 mg (16%) of
chelated complex 16b] from 840 mg (2.70 mmol) pen-
tacarbonyl-(1-methoxy-1-phenyl-methylidene)-chrom-
ium(0) (15b) and 816 mg (8.07 mmol) of 4-methyl-
amino-2-buten-1-ol (14); air-sensitive red oil; Rf
2
NCH3, NCH%3], 3.62 [d, J(3-Hexo/3-Hendo)=12.70 Hz,
1H, 3-Hendo], 4.14 [d, 2J(3-Hexo/3-Hendo)=12.70 Hz,
1H, 3-Hexo], 4.32 [dd, 2J(6-Hexo/6-Hendo)=2.44 Hz,
3J(5-H/6-Hexo)=8.30 Hz, 1H, 6-Hexo], 5.14 [dd, 3J(5-H/
1
(Et2O)=0.61, Rf (CH2Cl2)=0.12. H-NMR (acetone-
3
6-Hexo)=8.30 Hz, J(5-H/6-Hendo)=12.45 Hz, 1H, 5-
d6): l=3.97 [s, 3H, N–CH3], 4.18 [mc, 4H, 3-H, 6-H],
5.59 [mc, 2H, 4-H, 5-H], 7.17 [mc, 5H, Ph]. 13C-NMR
(acetone-d6): l=49.05 (NMe), 56.19 (3-C), 58.23 (6-C),
120.02 (m-Car), 124.49 (4-C), 126.40 (p-Car), 129.11
(o-Car), 136.11 (5-C), 153.33 (ipso-Car), 218.06 (cis-CO),
224.83 (trans-CO), 272.31 (1-C). IR (NaCl): w=3380
cm−1, 2965, 2860, 2065, 1970, 1935, 1920, 1400, 1260,
1020, 820, 660. MS (70 eV): m/z (%)=381 (21) [M+],
353 (12) [M+ −CO], 325 (29) [M+ −2 CO], 297 (15)
H], 5.28 [s, 5H, Cp]. 13C-NMR (CD3CN): l=27.63
(4-Me), 39.87 and 46.41 (NMe, NMe%), 48.25 (6-C),
76.17 (3-C), 84.30 (5-C), 88.92 (Cp-C), 92.01 (4-C),
228.87 (1-C). IR (KBr): w=3100 cm−1, 3040, 2900,
1700, 1555, 1460–1410, 1370, 1340, 1255, 1100–1000,
895, 840. MS (70 eV): m/z (%)=263 (35) [cation-H],
197 (21) [cation-CpH2], 127 (75), 124 (56) [CoCp+], 108
(22), 70 (54), 59 (100) [Co+], 41 (82), 28 (26) [CO+].
Anal. Calc. for C13H19BCoF4NO (351.0): C, 44.48; H,
5.45; N, 3.99. Found: C, 44.66; H, 5.42; N, 3.89%.
[M+ −3 CO], 269 (24) [M+ −4 CO], 241 (13) [M+
−
5 CO], 176 (85), 145 (37), 112 (100), 77 (63) [Ph+], 52
(45) [Cr+], 28 (68) [CO+]. Anal. Calc. for
C17H15CrNO6 (381.3): C, 53.55; H, 3.97; N, 3.67.
Found: C, 53.59; H, 4.00; N, 3.63%.
3.8. Synthesis of aminooxochromiumcarbene complexes
12 [6,12] from 14 and 15—general procedure
3.9. Photochemical synthesis of chelated (p2-alkene)am-
inochromiumcarbene complexes 16 from 12—general
procedure
Carbene complex 15 was dissolved in THF (10 ml
mmol−1) and then the amine 14 (1.2–2 equivalents)
was added at once. The colour of the mixture changed
from red to yellow within the following 5 min. This
mixture was allowed to stir for a further 3 h. All
volatile components were removed in vacuo and finally
the remaining crude product was purified by column
chromatography (silica gel, neat diethyl ether; first frac-
tion contains some residual starting material 15, second
fraction contains the product 12).
The irradiation apparatus described in the protocol
for the preparation of complex 9 was flushed with dry
nitrogen and then charged with a solution of the respec-
tive complex 12 in THF. The reaction mixture was
chilled to −30°C and then irradiated for 3 h at this
temperature. Then all volatile components were re-
moved in vacuo and the remaining crude product
metallacycle was finally purified by column chromatog-
raphy (silica gel, neat diethyl ether).
3.8.1. Pentacarbonyl-[(5Z)-3-aza-3-methyl-7-hydroxy-
5-hepten-2-ylidene]-chromium(0) (12a)
Yield: 2.11 g (47%) [beside 492 mg (12%) of chelated
complex 16a] from 3.52 g (14.07 mmol) pentacarbonyl-
(1-methoxy-1-ethylidene)-chromium(0) 15a (R/Me) and
2.74 g (27.06 mmol) of 4-methylamino-2-buten-1-ol 14;
air-sensitive red oil; Rf (Et2O)=0.57, Rf (CH2Cl2)=
3.9.1. Tetracarbonyl-[(4Z)-(4-5-p2)-2-aza-6-hydroxy-
1,2-dimethyl-4-hexen-1-ylidene]-chromium(0) 16a
Yield: 481 mg (77%) as an air-sensitive yellow oil
from 683 mg (2.14 mmol) of 12a; Rf (Et2O)=0.22, Rf
(CH2Cl2)=0.00. 1H-NMR (acetone-d6): l=2.38 [s,
1
3
0.10. H-NMR (acetone-d6): l=2.74 [s, 3H, 1-H], 3.31
3H, 1-CH3], 3.24 [s, 3H, NCH3], 3.53 [t, J(6-H/OH)=
[s, 3H, NCH3], 4.31 [mc, 4H, 4-H, 7-H], 5.82 [mc, 2H,
5-H, 6-H]. 13C-NMR (acetone-d6): l=40.42 (1-C),
40.80 (N–Me), 58.65 (4-C), 63.54 (7-C), 125.19 (5-C),
136.22 (6-C), 218.58 (cis-CO), 224.39 (trans-CO),
273.77 (2-C). IR (NaCl): w=3385 cm−1, 2960, 2855,
2055, 1970, 1940, 1930, 1530, 1400, 1260, 1025, 800.
10.84 Hz, 1H, O–H], 4.33 [mc, 6H, 3-H, 4-H, 5-H,
6-H]. 13C-NMR (acetone-d6): l=33.46 (1-Me), 38.52
(NMe), 61.64 (3-C), 62.02 (6-C), 76.49 (4-C), 87.65
(5-C), 224.92 and 225.92 (cis/eq-CO), 226.98 and
233.88 (trans-CO, cis/ap-CO), 275.50 (1-C). IR (NaCl):
w=3380 cm−1, 2960, 2855, 2020, 1940, 1930, 1840,
1445, 1225, 1130, 1020, 800, 740, 675. MS (70 eV): m/z
(%)=291 (23) [M+], 263 (14) [M+ −CO], 235 (36)
[M+ −2CO], 207 (17) [M+ −3 CO], 179 (25) [M+ −4
CO], 163 (76), 100 (74), 71 (100), 28 (54) [CO+]. Anal.
Calc. for C11H13CrNO5 (291.3): C, 45.15; H, 4.11; N,
4.39. Found: C, 45.22; H, 4.21; N, 4.31%.
MS (70 eV): m/z (%)=319 (17) [M+], 291 (9) [M+
−
CO], 263 (11) [M+ −2 CO], 235 (23) [M+ −3 CO],
207 (19) [M+ −4 CO], 179 (14) [M+ −5 CO], 163 (54),
100 (83), 71 (100), 28 (68) [CO+]. Anal. Calc. for
C12H13CrNO6 (319.2): C, 45.15; H, 4.11; N, 4.39.
Found: C, 45.22; H, 4.21; N, 4.29%.

124
S.-E. Eigemann, R. Schobert / Journal of Organometallic Chemistry 585 (1999) 115–126
3.9.2. Tetracarbonyl-[(4E)-(4-5-p2)-2-aza-6-hydroxy-2-
methyl-1-phenyl-4-hexen-1-ylidene]-chromium(0) 16b
Yield: 287 mg (72%) as an air-sensitive yellow oil
from 432 mg (1.13 mmol) of 12b; Rf (Et2O)=0.27, Rf
(CH2Cl2)=0.00. 1H-NMR (acetone-d6): l=3.06 [s,
3H, NCH3], 4.38 [mc, 7H, 3-H, 4-H, 5-H, 6-H, O–H],
6.84 [mc, 2H, m-Har], 7.19 [mc, 1H, p-Har], 7.39 [mc,
2H, o-Har]. 13C-NMR (acetone-d6): l=41.44 (NMe),
60.70 (3-C), 61.99 (6-C), 77.60 (4-C), 89.35 (5-C),
120.60 (m-Car), 127.06 (p-Car), 129.13 (o-Car), 149.64
(ipso-Car), 224.81 (cis/eq-CO), 224.87 (cis/eq-CO),
228.18 and 231.66 (trans-CO, cis/ap-CO), 276.23 (1-C).
IR (NaCl): w=3370 cm−1, 3060, 3020, 2965, 2930,
2055, 2000, 1875, 1860, 1690, 1600, 1555, 1540, 1440,
1405, 1260, 1210, 1100, 1020, 870, 810, 745, 655. MS
(70 eV): m/z (%)=353 (32) [M+], 325 (21) [M+ −CO],
297 (19) [M+ −2 CO], 269 (28) [M+ −3 CO], 241 (17)
[M+ −4 CO], 176 (71), 145 (48), 112 (100), 77 (82)
[Ph+], 52 (61) [Cr+], 28 (57) [CO+]. Anal. Calc. for
C16H15CrNO5 (353.3): C, 54.40; H, 4.28; N, 3.97.
Found: C, 54.46; H, 4.35; N, 4.01%.
‘amine smell’, b.p.=112°C, 0.02 Torr. 1H-NMR
(DMSO-d6): l=2.24 [s, 3H, NCH3], 3.09 [d, J(3-H/4-
3
H)=6.59 Hz, 2H, 4-H], 4.01 [d, 3J(1-H/2-H)=5.61
Hz, 2H, 1-H], 5.43 [dt, 3J(2-H/3-H)=11.72 Hz, 3J(3-H/
4-H)=6.59 Hz, 1H, 3-H], 5.60 [dt, 3J(2-H/3-H)=11.72
Hz, 3J(1-H/2-H)=5.61 Hz, 1H, 2-H]. 13C-NMR
(DMSO-d6): l=35.48 (N–Me), 47.83 (4-C), 57.11 (1-
C), 128.54 (3-C), 132.11 (2-C).
3.11. Synthesis of functionalized amines from their
hydrochlorides—general procedure
An 18% solution of ammonia in dichloromethane (1
l) was freshly prepared by saturation of the solvent with
NH3 gas at −18°C (it can be stored at −20°C for
some time). Two to three equivalents of this solution
were added to a suspension of the respective hydrochlo-
ride in chloroform (1.00 ml mmol−1), whereupon a
white precipitate of ammonium chloride was instantly
formed. After stirring of the mixture for a further hour,
it was filtered, the residue was thoroughly washed with
dichloromethane and then the combined organic phases
were concentrated on a rotary evaporator (temperature
was kept below 35°C). The residue thus obtained, was
dried in vacuo to give a colourless, viscous oil, clean
enough to be used as such without further purification.
Storage of these amines is possible under an atmo-
sphere of argon at −20°C for a couple of days. Yields:
aminoacetonitrile 91%, methylaminoacetonitrile 74%,
glycine methylester 89%, sarcosine methylester 65%,
b-alanine methylester 99%.
3.10. (Z)-4-Methylamino-2-buten-1-ol (14) [20]
3.10.1. (Z)-4-Chloro-2-buten-1-ol
(Z)-2-Butene-1,4-diol (50.00 g, 568 mmol) and
pyridine (37.50 ml, 478 mmol) were dissolved in diethyl
ether (100 ml). The resulting solution was then chilled
to −5°C and treated with thionyl chloride (41 ml)
during which operation the temperature was not al-
lowed to exceed +5°C. After completion of the addi-
tion, stirring of the mixture was continued for another
2 h. Then water (150 ml) was added, the phases were
separated, and after repeated extraction of the aqueous
one with diethyl ether (2×30 ml) and dichloromethane
(2×30 ml), the combined organic layers were dried
over MgSO4 and filtered. All volatile components were
removed on a rotary evaporator and the remaining
residue was purified by distillation in a Kugelrohr
apparatus. Yield: 28.19 g (47%) as a colourless liquid of
a burning odour, b.p.=76°C, 13 Torr. 1H-NMR
(DMSO-d6): l=4.16 [mc, 4H, 1-H, 4-H], 4.45 [s, 1H,
O–H], 5.55 [mc, 2H, 2-H, 3-H]. 13C-NMR (DMSO-d6):
l=40.10 (4-C), 57.00 (1-C), 125.64 (3-C), 135.34 (2-C).
3.12. Synthesis of allylaminomanganesecarbene
complexes 13 and 19 from 17—general procedure
Under an atmosphere of dry nitrogen (h5-cyclopenta-
dienyl)-benzylidyne-dicarbonyl-manganese(III)
tetra-
chloroborate (17) was dissolved in dry dichloromethane
(30 ml mmol−1) and the resulting solution chilled to
−78°C. One equivalent of the respective allylamine
(together with an excess of pyridine or TEA as a base)
was added at once, whereupon an instantaneous change
of the colour from yellow to red occurred and a white
precipitate of ammonium tetrachloroborate was
formed. The solution was allowed to warm up to
ambient temperature with continued stirring and was
finally concentrated on an oil pump to a volume of ca.
5 ml. By column chromatography of this solution on
silica gel with neat diethyl ether and evaporation of the
eluate pure complexes 13 and 19 were obtained. Dicar-
bonyl-(h5-cyclopentadienyl)-(2-aza-2-methyl-1-phenyl-
4-penten-1-ylidene)-manganese(I) (19)
3.10.2. (Z)-4-Methylamino-2-buten-1-ol (14)
To a solution of (Z)-4-chloro-2-buten-1-ol (10.36 g,
97.20 mmol) in dichloromethane (150 ml) was added
methylamine (10 ml). The resulting mixture was stirred
overnight and then filtered to remove any precipitated
methylammonium chloride, which was washed thor-
oughly with dichloromethane. The combined clear
filtrate and washings were concentrated on a rotary
evaporator and the crude product thus obtained was
finally purified by distillation in a Kugelrohr apparatus.
Yield: 4.16 g (42%), colourless liquid with a typical
Yield: 284 mg (55%) as an air-sensitive red oil from
680 mg (1.63 mmol) 17, 1.00 ml (12.50 mmol) pyridine,
and 1.00 ml (14.62 mmol) of allylmethylamine; Rf
(Et2O)=0.95, Rf (benzene)=0.65. Mixture (1:0.52) of

S.-E. Eigemann, R. Schobert / Journal of Organometallic Chemistry 585 (1999) 115–126
125
E/Z isomers as to the configuration about the 1C–2N
bond. Assignment of the NMR-signals by their integra-
tion where possible, isomers indicated as 191 (E isomer)
and THF (100 ml). The solution was chilled to −30°C
and then irradiated for 3 h. All volatile components
were removed in vacuo and the remaining crude
product was finally purified by column chromatography
(silica gel, neat diethyl ether). 260 mg (94%) as an
air-sensitive red oil; Rf (Et2O)=0.91, Rf (benzene)=
0.96. 1H-NMR (benzene-d6): l=1.57 [mc, 3H, 4-H,
5-H], 1.98 [s, 3H, NCH3], 2.27 [mc, 2H, 3-H], 3.75 [s,
5H, Cp], 6.77 [mc, 5H, Ph]. 13C-NMR (benzene-d6):
l=33.38 (5-C), 38.04 (NMe), 41.56 (3-C), 51.95 (4-C),
86.14 (Cp-C), 120.33 (m-Car), 124.58 (m-Car), 126.33
(p-Car), 127.55 (o-Car), 128.43 (o-Car), 151.66 (ipso-Car),
241.61 (CO), 281.87 (1-C). IR (NaCl, THF): w=3410
cm−1, 2955, 2280, 1965, 1925, 1850, 1460, 755, 705,
655. MS (70 eV): m/z (%)=307 (22) [M+], 279 (77)
[M+ −CO], 223 (37) [C12H10MnN+], 158 (32)
[C7H5MnN+], 120 (49) [C5H5Mn+], 118 (51)
[C5H3Mn+], 105 (86) [C4H2Mn+], 77 (35) [C6H5+], 55
(42) [Mn+], 42 (100) [C3H6+]. Anal. Calc. for
C17H18MnNO (307.3): C, 66.45; H, 5.91; N, 4.56.
Found: C, 66.51; H, 5.86; N, 4.59%.
1
and 192 (Z isomer): H-NMR (benzene-d6): l=2.09 [s,
2H, 3-H], 3.08 [s, 3H, NCH23], 3.24 [s, 3H, NCH31], 3.88
[s, 5H, Cp], 4.61 [mc, 3H, 4-H, 5-H], 6.76 [mc, 5H, Ph].
13C-NMR (acetone-d6): l=42.22 (NMe2), 46.46
(NMe1), 59.75 (3-C1), 64.09 (3-C2), 84.37 (Cp2), 85.09
(Cp1), 117.69 (5-C1), 118.89 (5-C2), 120.49 (m-Car2),
120.80 (m-Car1), 124.98 (p-Car2), 125.02 (p-Car1), 127.77
(o-Car1), 128.25 (o-Car2), 132.40 (4-C2), 133.29 (4-C1),
154.23 (ipso-Car1), 154.62 (ipso-Car2), 234.12 (CO2),
234.95 (CO1), 283.70 (1-C1), 285.05 (1-C2). IR (NaCl,
THF): w=2975 cm−1, 2680, 1965, 1920, 1855, 1460,
1365, 655. MS (70 eV): m/z (%)=335 (23) [M+], 307
(4) [M+ −CO], 279 (100) [M+ −2 CO], 223 (40)
[C12H10MnN+], 158 (23) [C7H5MnN+], 120 (49)
[C5H5Mn+], 55 (39) [Mn+]. Anal. Calc. for
C18H18MnNO2 (353.3): C, 64.48; H, 5.41; N, 4.18.
Found: C, 64.53; H, 5.46; N, 4.13%.
3.12.1. Dicarbonyl-(p5-cyclopentadienyl)-[(4Z)-2-aza-6-
hydroxy-2-methyl-1-phenyl-4-hexen-1-ylidene]-manga-
nese(I) (13)
Acknowledgements
Yield: 440 mg (49%) as an air-sensitive red oil from
1.04 mg (2.49 mmol) 17, 1 ml triethylamine, and 2.00 g
(19.77 mmol) of aminobutenol 14; Rf (Et2O)=0.65, Rf
(benzene)=0.00. Mixture (1:0.7) of E/Z isomers as to
the configuration about the 1C–2N bond. Assignment
of the NMR-signals by their integration where possible;
isomers indicated as 131 (E isomer) and 132 (Z isomer):
1H-NMR (benzene-d6): l=2.42 [s, 2H, 3-H], 3.54 [s,
3H, NCH3], 4.14 [s, 5H, Cp], 4.91 [mc, 2H, 6-H], 5.57
[mc, 2H, 4-H, 5-H], 6.86 [mc, 5H, Ph]. 13C-NMR
(benzene-d6): l=42.29 (NMe2), 46.42 (NMe1), 54.72
(3-C1), 58.17 (3-C2), 58.81 (6-C1), 68.93 (6-C2), 84.51
(Cp2), 84.93 (Cp1), 120.46 (m-Car2), 121.00 (m-Car1),
124.99 (p-Car2), 125.08 (p-Car1), 127.35 (o-Car2), 127.39
(o-Car1), 128.54 (4-C1), 131.29 (4-C2), 133.20 (5-C1),
134.02 (5-C2), 154.20 (ipso-Car2), 154.48 (ipso-Car2),
234.36 (CO2), 234.80 (CO1), 282.88 (1-C2), 283.12 (1-
C1). IR (NaCl): w=3375 cm−1, 2960, 1905, 1840, 1595,
1505, 1435, 1395, 1360, 1260, 1185, 1025, 805, 705, 655.
MS (70 eV): m/z (%)=365 (43) [M+], 309 (100)
[M+ −2 CO], 243 (47) [M+ −C7H6O2], 223 (27)
[C12H10MnN+], 120 (100) [C5H5Mn+], 77 (38),
[C6H5+], 66 (23) [C5H6+], 55 (70) [Mn+]. Anal. Calc. for
C19H20MnNO3 (365.3): C, 62.47; H, 5.52; N, 3.83.
Found: C, 62.37; H, 5.46; N, 3.79%.
We thank the German Fonds der Chemischen Indus-
trie e.V. and the Deutsche Forschungsgemeinschaft for
financial support.
References
[1] W. Fo¨rtsch, F. Hampel, R. Schobert, Chem. Ber. 130 (1997) 863.
[2] (a) J. Bo¨hmer, W. Fo¨rtsch, F. Hampel, R. Schobert, Chem. Ber.
129 (1996) 427. (b) R. Schobert, Chem. Ber. 129 (1996) 595. (c)
W. Fo¨rtsch, F. Hampel, R. Schobert, J. Organomet. Chem. 526
(1996) 169. (d) J. Bo¨hmer, F. Hampel, R. Schobert, Synthesis
(1997) 661.
[3] R. Aumann, H. Ring, C. Kru¨ger, R. Goddard, Chem. Ber. 112
(1979) 3644.
[4] (a) R. Schobert, F. Hampel, K.-D. Roth, M. Sto¨ss, J.
Organomet. Chem. 493 (1995) 113. (b) For a thorough investiga-
tion of the synthesis and chemistry of cobaltalactones see also:
S.D.R. Christie, C. Cosset, D.R. Hamilton, W.J. Kerr, J.M.
O’Callaghan, J. Chem. Soc. Chem. Commun. (1995) 2051.
[5] B.C. So¨derberg, L.S. Hegedus, M.A. Sierra, J. Am. Chem. Soc.
112 (1990) 4364.
[6] M.A. Schwindt, J.R. Miller, L.S. Hegedus, J. Organomet. Chem.
413 (1991) 143.
[7] (a) C.A. Toledano, H. Rudler, J.-C. Daran, Y, Jeannin, J. Chem.
Soc. Chem. Comm. (1984) 574. (b) C.A. Toledano, A. Parlier, H.
Rudler, J.-C. Daran, Y, Jeannin, J. Chem. Soc. Chem. Comm.
(1984) 576. (c) C. Alvarez, A. Parlier, H. Rudler, R. Yefsah,
J.-C. Daran, C. Knobler, Organometallics 8 (1989) 2253. (d)
C.A. Toledano, J. Levisalles, M. Rudler, H. Rudler, J.-C. Daran,
Y, Jeannin, J. Organomet. Chem. 228 (1982) C7.
3.13. (p5-Cyclopentadienyl)-carbonyl-[(4-5-p2)-2-aza-2-
methyl-1-phenyl-4-penten-1-ylidene]-manganese(I) (18)
[8] M.J. McGeary, T.L. Tonker, J.L. Templeton, Organometallics 4
(1985) 2102.
[9] (a) R. Aumann, E.O. Fischer, Chem. Ber. 101 (1968) 954. (b)
E.O. Fischer, R. Aumann, Chem. Ber. 101 (1968) 963. (c) E.O.
The irradiation apparatus described in the protocol
for the preparation of complex 9 was flushed with dry
nitrogen and then charged with 19 (304 mg, 0.90 mmol)

126
S.-E. Eigemann, R. Schobert / Journal of Organometallic Chemistry 585 (1999) 115–126
Fischer, H.J. Kollmeier, Angew. Chem. 82 (1970) 325; Angew.
Chem. Int. Ed. Engl. 9 (1970) 309.
Chem. 107 (1976) C23. (c) E.O. Fischer, W. Kleine, F.R. Kreißl,
Angew. Chem. 88 (1976) 646; Angew. Chem. Int. Ed. Engl. 15
(1976) 616. (d) E.O. Fischer, R.L. Clough, G. Besl, F.R. Kreißl,
Angew. Chem. 88 (1976) 584; Angew. Chem. Int. Ed. Engl. 15
(1976) 543. (e) E.O. Fischer, P. Rustemeyer, J. Organomet. Chem.
225 (1982) 265.
[10] U. Klabunde, E.O. Fischer, J. Am. Chem. Soc. 89 (1967) 7141.
[11] B.C. So¨derberg, L.S. Hegedus, Organometallics 9 (1990) 3113.
[12] (a) H. Rudler, A. Parlier, B. Denise, R. Yefsah, C. Alvarez, J.C.
Daran, J. Vaissermann, C. Knobler, J. Organomet. Chem. 358
(1988) 245. (b) A. Parker, R. Yefsah, H. Rudler, M. Rudler, J.C.
Daran, J. Vaissermann, J. Organomet. Chem. 381 (1990) 191.
[13] D.B. Grotjahn, K.H. Do¨tz, Synlett (1991) 381
[16] D.F. Harvey, D.M. Sigano, Chem. Rev. 96 (1996) 271.
[17] E.O. Fischer, T. Selmayr, F.R. Kreißl, Chem. Ber. 110 (1977) 2947.
[18] E.O. Fischer, E.W. Meineke, F.R. Kreißl, Chem. Ber. 110 (1977)
1140.
[14] P.F. Engel, M. Pfeffer, Chem. Rev. 95 (1995) 2281.
[15] (a) E.O. Fischer, W. Schambeck, J. Organomet. Chem. 201 (1980)
311. (b) E.O. Fischer, W. Kleine, F.R. Kreißl, J. Organomet.
[19] J.H. Biel, J. Am. Chem. Soc. 71 (1949) 1306.
[20] J. Cologne, G. Poilane, Soc. Chim. (1955) 953.
.
.