Synthesis of configurationally stable, optically active organocobalt compounds

Article abstract of DOI:10.1021/om990517n

The transmetalation reaction between a series of ortho-lithiated tertiary amine derivatives (N∧C-Li) and [η⁵-C5H₅)CoI₂]₂ affords a series of cobaltacyclic compounds of the general form (η⁵-C₅H₅)Co(C∧N)I, in which the cobalt center is in a pseudotetrahedral environment. With optically active lithiated compounds, such as those obtained from (R)- or (S)-1-(dimethyl-amino)-1-phenylethane, the reaction forms a mixture of two diastereoisomers (R_C,R_Co)-12a, (R_C,S_Co)-12a′ and (S_C,S_Co)-12b′, (S_C,S_Co)-12b′, respectively, of which the isomers 12a and 12b′ are predominant, as they are formed with a de of 90%. ¹H NMR studies indicate that the compounds are configurationally stable at the cobalt center. Reaction of these species with neutral ligands such as phosphines, phosphites, or isocyanides led to the formation of cationic complexes via substitution of the iodide ligand, this reaction occurring mainly with retention of configuration for the optically active species.

Full text of DOI:10.1021/om990517n

5560
Organometallics 1999, 18, 5560-5570
Syn th esis of Con figu r a tion a lly Sta ble, Op tica lly Active
Or ga n ocoba lt Com p ou n d s
Mario Roberto Meneghetti,†,‡ Mary Grellier,† Michel Pfeffer,*,†
J airton Dupont,‡ and J ean Fischer§
Laboratoire de Synthe`ses Me´tallo-Induites and Laboratoire de Cristallochimie et Chimie
Structurale, UMR 7513 du CNRS, 4, rue Blaise Pascal, 67000 Strasbourg France, and
Laboratory of Molecular Catalysis, IQ/ UFRGS, Av. Bento Gonc¸alves,
9500-Porto Alegre, 91501-970 RS, Brazil
Received J uly 6, 1999
The transmetalation reaction between a series of ortho-lithiated tertiary amine derivatives
(N∧C-Li) and [(η5-C5H5)CoI2]2 affords a series of cobaltacyclic compounds of the general form
(η5-C5H5)Co(C∧N)I, in which the cobalt center is in a pseudotetrahedral environment. With
optically active lithiated compounds, such as those obtained from (R)- or (S)-1-(dimethyl-
amino)-1-phenylethane, the reaction forms a mixture of two diastereoisomers (RC,RCo)-12a ,
(RC,SCo)-12a ′ and (SC,RCo)-12b, (SC,SCo)-12b′, respectively, of which the isomers 12a and
1
12b′ are predominant, as they are formed with a de of 90%. H NMR studies indicate that
the compounds are configurationally stable at the cobalt center. Reaction of these species
with neutral ligands such as phosphines, phosphites, or isocyanides led to the formation of
cationic complexes via substitution of the iodide ligand, this reaction occurring mainly with
retention of configuration for the optically active species.
In tr od u ction
rahedral arene or cyclopentadienyl “half-sandwich”
transition-metal complexes. Recently we have been
involved in the synthesis of related (arene)ruthenium
compounds based upon cyclometalated tertiary amino
ligands. When synthesizing these starting materials
with optically active 1-(dimethylamino)-1-phenylethane
derivatives, we isolated the optically active ruthena-
cycles (RC,SRu)- and (RC,RRu)-[(η6-C6H6)Ru(C6H4CH(Me)-
NMe2)Cl] displaying a configurationally stable Ru cen-
ter. In each case these compounds were a 20:1 mixture
of two diastereoisomers.14 These results prompted us
to investigate the synthesis of related cyclopentadienyl-
cobalt(III) species with the same optically active che-
lates.
Among the large variety of organocobalt(III) com-
pounds reported in the literature, it appeared that only
very few examples of cobalt hydrocarbyls, intramolecu-
larly stabilized by a heteroatom coordinating group,
exist.15 This is rather surprising, as the compound Co-
(C6H4CH2NMe2-o)316 was described more than 30 years
ago. Recently a new type of this compound was synthe-
Optically active organometallic compounds have long
been fascinating molecules for synthetic chemists in-
terested in the field of metal-mediated synthesis. Part
of this interest is due to the fact that they provide
valuable tools for the investigation of the stereochemical
course of reactions. Moreover, they may provide access
to new catalysts that can be used in asymmetric C-C
or C-H bond synthesis.1
Since the first example of the synthesis and resolution
of optically active organometallic complexes containing
a stereogenic metal center,2 related work has been
performed mainly with metals such as Ti,3 Co,4 Cr,5 Mo,6
W,7 Mn,8 Re,9 Fe,10 Ir,11 Ru,12 Rh,13 etc. Among these
examples a burst of activity was devoted to pseudotet-
† Laboratoire de Synthe`ses Me´tallo-Induites, UMR 7513 du CNRS.
‡ Laboratorio de Sintese Assimetrica, IQ/UFRGS.
§ Laboratoire de Cristallochimie et Chimie Structurale, UMR 7513
du CNRS.
(1) (a) Omae, I. In Applications of Organometallic Compounds;
Wiley: Chichester, U.K., 1998; Chapter 20. (b) Trost, B. M.; van
Vranken, D. L. Chem. Rev. 1996, 96, 395. (c) Noyori, R. In Asymmetric
Catalysis in Organic Synthesis; Wiley: New York, 1994. (d) Brookhart,
M.; Timmers, D.; Tucker, Willians, J . R.; G. D. J . Am. Chem. Soc. 1983,
105, 6721. (e) Hagashi, T.; Konixhi, M.; Ito, H.; Kumada, M. J . Am.
Chem. Soc. 1982, 104, 4962. (f) Kagan, H. In Comprehensive Organo-
metallic Chemistry; Wilkinson, G., Stone, F. G. A., Abel, E. W., Eds.;
Pergamon Press: Oxford, U.K., 1982; Vol. 8. (g) Ba¨ckvall, J . E.; Andell,
D. S. J . Chem. Soc., Chem. Commun. 1981, 1098; (h) Brunner, H.
Angew. Chem., Int. Ed. 1999, 38, 1195.
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H. Angew. Chem., Int. Ed. Engl. 1969, 8, 382.
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Viguri, F.; Mir, C.; Cativiela, C.; de V´ıu, M. P. L.-R. Organometallics
1998, 17, 2986.
(12) (a) Consiglio, G.; Morandini, F. Chem. Rev. 1987, 87, 761 and
references cited therein. (b) Brunner, H.; Neuhierl, T.; Nuber, B. J .
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Chem. Res. 1997, 30, 97. (d) Bruce, M. I.; Hall, B. C.; Zaitseva, N. N.;
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Brunner, H.; Oeschey, R.; Nuber, B. J . Chem. Soc., Dalton Trans. 1996,
1499. (f) Enders, D.; Gielen, H.; Raabe, G.; Runsink, J .; Teles, H. Chem.
Ber./ Recl. 1997, 130, 1253.
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M. K. J . Chem. Soc., Chem. Commun. 1996, 961. (b) Carmona, D.;
Lahoz, F. J .; Oro, L. A.; Lamata, M. P.; Viguri, F.; San J ose, E.
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Pfeffer, M. Organometallics 1995, 14, 4559.
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Organometallic Chemistry; Wilkinson, G., Stone, F. G. A., Abel, E. W.,
Eds.; Pergamon Press: Oxford, U.K., 1982; Vol. 5. (b) Sweany, R. L.
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F. G. A., Abel, E. W., Eds.; Pergamon Press: Oxford, U.K., 1994; Vol.
8.
10.1021/om990517n CCC: $18.00 © 1999 American Chemical Society
Publication on Web 11/30/1999

Optically Active Organocobalt Compounds
Organometallics, Vol. 18, No. 26, 1999 5561
Ta ble 1. Yield s of Com p ou n d s 3 Obta in ed via Eq 1
sized by Werner et al. via a (3 + 2) cycloaddition of a
terminal alkyne and an iminoacylcobalt(III) derivative.17
We report herein the successful transmetalation
reaction between a series of ortho-lithiated tertiary
amine derivatives and [CpCoI2]2, which afforded high
yields of the expected pseudotetrahedral organocobalt
compd 3
4-R
5-R
6-R
yield (%)
3a
3b
3c
3d
3e
3f
H
H
H
H
H
H
H
H
H
78
86
70
70
48
59
4
Me
H
H
Me
H
F
H
MeO
H
F
H
3g
MeO
compounds.
Resu lts a n d Discu ssion
mixture. This phenomenon may be related to a better
solubility of 2a in these solvents and hence to a high
reactivity of 2a toward the Co(III), which might be
detrimental to the isolation of the desired half-sandwich
cobaltacycle complex 3.
(η5-Cyclopentadienyl)[2-((dimethylamino)methyl)phe-
nyl]cobalt iodide (3a ) was isolated as a green powder.
It was both air- and water-stable, this stability being
somehow reminiscent to that of Co(C6H4CH2NMe2)3.16
3a was readily characterized through 1H and 13C
NMR spectroscopy. The complex 3a displayed typical
chemical shifts for a diastereotopic CH2NMe2 unit.
However, combustion analysis proved to be somewhat
frustrating, as for 3a and the related compounds 3 of
this series the carbon values were often higher than the
theoretical amounts, despite all our efforts to crystallize
the compounds and/or to dry the obtained crystals in
vacuo. Nevertheless, the ambiguity surrounding the
purity of 3a was practically overcome when studying
the corresponding cationic compounds (see below), for
which we obtained satisfactory elemental analyses.
We recently described the facile synthesis of pseudo-
tetrahedral ruthenium derivatives by means of a trans-
metalation reaction whereby the [(dimethylamino)-
methyl]aryl ligand was transferred from Hg(C6H4CH2N-
Me2)2 to a ruthenium(II) center, [(η6-C6H6)RuCl2)]2,
affording high yields of [(η6-C6H6)Ru(C6H4CH2NMe2)-
Cl]. This latter compound displayed an interesting
reactivity, as it led to the synthesis of quinolinium
derivatives by reactions with internal alkynes.18 We
thus chose [(η5-C5H5)CoI2]2 (1) as the starting material
because it could lead to Co(III) derivatives isostructural
with the Ru compounds. 1 is readily available through
oxidation of CpCo(CO)2 by I2.19 This compound was
extensively studied by Maitlis et al., and surprisingly
it seemed not to have been used as a starting material
in transmetalation reactions. Most of the related trans-
metalation reactions (with alkyllithium or Grignard
derivatives) have been performed using CpCo(L)I2 (L )
CO, PR3) instead.15a,20
We found that 1 was a much better starting material
than CpCo(CO)I2, as it afforded high yields of 3a 21 when
the transmetalation reaction was performed in toluene
at room temperature in the presence of 2a ([2-((di-
methylamino)methyl)phenyl]lithium) (eq 1). In a typical
Several compounds related to 3a were synthesized by
following the same procedure as for 3a by reactions of
lithiated derivatives of substituted dimethylbenzyl-
amines (2b-g) according to eq 1. The results are
summarized in Table 1. It is clear from this series of
compounds that there should be significant interaction
between the Cp ring and the second substituent ortho
to the cobalt atom (i.e., Me, F, and OMe), thus prevent-
ing the formation of the expected aryl-Co compounds
with these latter substituents. On the other hand, there
seems to be only a marginal difference in the yields for
the synthesis of para- and meta-substituted Co-aryl
derivatives. We believe, however, that the low yield
observed for 3g might be related to a better solubility
of the lithiated ligand as compared to the other reagent,
this being in line with the reactions performed in THF
or Et2O (see above).
A transmetalation reaction using 4 ([8-(dimethyl-
amino)-1-naphthyl]lithium) with 1 allowed the synthe-
sis of 5 in good yields (eq 2). The diastereotopicity of
reaction 2a was added to a suspension of 1 in toluene.
The solution turned gradually from black to dark green,
and after ca. 18 h of stirring the reaction was complete,
affording 3a after workup.22 We found that the best
yield of 3a was obtained when the reaction was per-
formed in the absence of solvents such as THF and Et2O.
With these solvents, the reaction of 2a with 1 led to
rapid and extensive decomposition and we could not
isolate any organocobalt(III) species from the reaction
(16) Cope, A. C.; Gourley, R. N. J . Organomet. Chem. 1967, 8, 527.
(17) Werner, H.; Xiaolan, L.; Peters, K.; von Schnering, H. G. Chem.
Ber./ Recl. 1997, 130, 565.
(18) Abbenhuis, H. C. L.; Pfeffer, M.; Sutter, J . P.; de Cian, A.;
Fischer, J .; Li J i, H.; Nelson, J . H. Organometallics 1993, 12, 4464.
Pfeffer, M.; Sutter, J .-P.; Urriolabeitia, E. P. Bull. Soc. Chim. Fr. 1997,
134, 947. Ferstl, W.; Sakodinskaya, I. K.; Beydoun-Sutter, N.; Le
Borgne, G.; Pfeffer, M.; Ryabov, A. D. Organometallics 1997, 16, 411.
(19) King, R. B. Inorg. Chem. 1966, 5, 82.
(20) Roe, D. M.; Maitlis, P. M. J . Chem. Soc. A 1971, 3173.

5562 Organometallics, Vol. 18, No. 26, 1999
Meneghetti et al.
Ta ble 2. Syn th esis of Ca tion ic Com p lexes
Accor d in g to Eq 5
the NMe2 group allowed us to conclude that it is
isostructural with the series of complexes of type 3.
This transmetalation could also be extended to
pseudoaromatic rings such as 7 ([(2-((dimethylamino)-
methyl)ferrocenyl]lithium).23 This reaction was, how-
ever, accompanied by some decomposition products that
were difficult to remove from the desired neutral cobalt
compound. Nevertheless, it was possible to obtain the
cationic derivative 8 as a single pair of enantiomers by
adding trimethylphosphine to the transmetalation reac-
tion mixture, analogous to those described below (eq 3).
complex
L
reacn time (h)
yield(%)
6a
6b
6c
6d
6ea
6f
PMe2Ph
PPh2Me
PMe3
P(OMe)3
PO(OMe)2
CNtBu
1
1
1
7
18
3
86
87
87
72
87
47
a
Obtained from P(OMe)3.
coordinate to the cobalt center. Trimethyl phosphite
could also react with 3a to afford 6d . It is noteworthy
that this reaction was rather slow, compared to the
previous ones, as it took ca. 7 h to reach completion.
When this latter reaction was run for a total reaction
time of 18 h, no 6d was obtained, but we observed
instead the quantitative formation of 6e. The formation
of the latter could be rationalized as the result of a
typical Arbusov reaction.25
Op tica lly Active Or ga n ocoba lt Com p ou n d s. Us-
ing the same procedure as for the synthesis of 3a -g
with the optically active reagents 11a and 11b, we could
obtain high yields of the optically active compounds
12a ,a ′ and 12b,b′ (eq 6).
However, in the absence of a crystal structure analysis
of 8 the relative configurations of both the Co and the
Fe centers remain uncertain.
To verify the influence of different alkyl substituents
on the N atom coordinated to the cobalt center, 1 was
allowed to react with 9 ([2-((ethylmethylamino)methyl)-
phenyl]lithium). This transmetalation reaction yielded
a mixture of the two pairs of diastereoisomers 10a and
10b in a 4:1 ratio. No difference in this diastereoisomeric
ratio was observed when, after 3 days, solutions of 10a ,b
in CDCl3 and acetone-d6 were analyzed (eq 4).
Red cationic complexes could be obtained by allowing
3a to react with neutral ligands even in solvents such
as CH2Cl2 (eq 5). The resulting complexes are soluble
in these solvents as well as in water. Pure compounds
were thus isolated from the latter solution in the
presence of KPF6, affording 6a -f in good to excellent
yields (see Table 2). Only phosphines with a small cone
angle24 could be used, as PPh3 proved to be too bulky to
The transmetalation reactions occurred in very much
the same way as for the corresponding ruthenium
(22) Alternative approaches to the synthesis of 3 via either C-H
activation (of dimethylbenzylamine) in the presence of a base or
oxidative addition of 2-I-C6H3CH2NMe2 to CpCo(CO)2 failed.
(23) Slocum, D. W.; Rockett, B. W.; Hauser, C. R. J . Am. Chem. Soc.
1965, 87, 1241.
(24) Shriver, D. F.; Atkins, P. W.; Langford, C. H. In Inorganic
Chemistry; Oxford University Press: Oxford, U.K., 1994.
(25) Huheey, J . E. Inorganic Chemistry: Principles of Structure and
Reactivity; Harper & Row: New York, 1978.
(21) CpCo(CO)I2 led only to “intractable materials” when used under
similar conditions.

Optically Active Organocobalt Compounds
Organometallics, Vol. 18, No. 26, 1999 5563
Ta ble 3. Selected Bon d Dista n ces (Å) a n d An gles
(d eg) for 12a a
Co-C(Cp) av
C-C av (Cp)
C-C av (Ph)
Co-I
2.073(8)
1.39(2)
1.39(2)
2.6291(7)
1.70(5)
2.024(4)
Co-C(15)
N-C(6)
1.924(5)
1.481(6)
1.469(7)
1.526(7)
1.39(1)
N-C(7)
N-C(8)
C(10)-C(15)
C(8)-C(10)
Co-Cpa
Co-N
1.51(1)
N-C(8)-C(9)
N-C(8)-C(10)
C(9)-C(8)-C(10)
Cpa-Co-I
114.5(6)
106.3(4)
115.1(8)
131.3(1)
124.1(3)
131.3(1)
95.7(1)
I-Co-C(15)
90.7(1)
84.2(2)
N-Co-C(15)
C(6)-N-C(7)
C(6)-N-C(8)
C(7)-N-C(8)
N-C(8)-C(10)
C(7)-N-Co-I
108.6(4)
108.5(4)
110.2(4)
116.1(5)
-60(2)
Cpa-Co-C(15)
F igu r e 1. ORTEP view of (RCo,RC)-(η5-C5H5)Co(C6H4CH-
(Me)NMe2)I (12a ).
Cpa-Co-N
I-Co-N
a
Cpa represents the centroid of the cyclopentadienyl ring.
containing compounds described earlier.14,26 These com-
pounds proved to be stable toward interconversion in
solution. No epimerization of 12a into 12a ′ could be
observed in solution, for instance, over a period of 7 days
at room temperature in either CDCl3 or d6-acetone.
Hence, the stereoselectivity of the transmetalation
reaction can be calculated from the ratio of the inte-
grated intensities of the 1H NMR signals. We found that
the ratios 12a :12a ′ and 12b′:12b amount to 19:1 (de )
91%). This de is very close to that determined for the
corresponding chloro derivative of the Ru compound
(90%), but it is lower than those for the iodo derivatives
which were obtained from the latter via a halide
metathesis reaction (de ) 94%). The ratio 12a :12a ′ could
not be improved by fractional crystallization or column
chromatography. The solid-state structure of 12a was
unambiguously determined via a single-crystal X-ray
diffraction study (see Figure 1). 12a and 12a ′ displayed
comparable crystallization rates so that the bulk sample
from which X-ray-quality crystals were obtained con-
tained the same ratio of both diastereoisomers as
determined above. Thus, we assume that the crystal
structure depicted in Figure 1 is that of the major
species, since the crystals of this species have a much
higher statistical chance of being isolated from the
mixture of diastereoisomers.27 The molecular structure
is represented in Figure 1, together with the adopted
numbering scheme. Selected bond distances and angles
are shown in Table 3.
The structure of 12a is that of a “three-legged piano
stool” in which the C and the N atoms of the arylamino
ligand and the iodide occupy the three “leg” positions.
The absolute configuration at cobalt is assigned by
assuming the following priority numbers: 1 (I atom), 2
(η5-cyclopentadienyl ligand), 3 (N atom), and 4 (phenyl
C atom). Thus, 12a is designated as the RC,RCo diaste-
reoisomer.28
The five-membered chelate ring is puckered. This is
best visualized in a Newman projection of 12a (see
Scheme 1), which is viewed along the N-Co axis. The
ring puckering is related to the torsion angle observed
between Co-C(15) and C(8)-N. This puckering is most
probably due to some steric repulsion between the Cp
ring and the benzylic methyl unit C(9), which forces the
Sch em e 1. Con for m a tion s of th e F ive-Mem ber ed
a
Ch ela te Rin g in 12a a n d 12a ′
a
The Newman projections of the organocobalt compounds
are viewed along the Co-N axis.
F igu r e 2. CD spectra of 12a ,a ′ and 12b,b′.
latter to be in an equatorial position with respect to the
metalated aryl ring. As a consequence of this situation,
the methyl C(7) on the nitrogen atom is in a staggered
position with the iodide atom (torsion angle C(7)-N and
Co-I ∼60°, λ conformation for the ring puckering). It
is most likely that this ring puckering is very much
different in the other diastereoisomer 12a ′, as the
benzylic proton and one of the methyls of the NMe2
group display a remarkable difference in their chemical
shift in comparison with those of the diastereoisomer
12a . The former is deshielded by 0.50 ppm, whereas the
methyl is shielded by 0.55 ppm, thus indicating that
they are in different magnetic environments. We shall
propose later a conformation for the five-membered
chelate ring in this isomeric form.
The configuration at the cobalt centers of the other
diastereoisomer 12b ,b ′ have been ascertained by the
comparison of the CD spectra of 12a ,a ′ and of 12b,b′.
As is expected for configurationally rigid diastereoiso-
mers, these CD spectra are mirror images of each other
(see Figure 2). Thus, we can assign to the major isomer
12b′ (SCo,SC) a configuration opposite that of 12a
(26) Pfeffer, M.; Sutter, J . P.; Urriolabeitia, E. P. Inorg. Chim. Acta
1996, 249, 63.
(27) Unfortunately, an NOE experiment did not allow the unam-
biguous identification of the relative positions of the CH(CH3) group
with respect to the Cp ring, as there is no NOE effect between these
groups.
(28) Stanley, K.; Baird, M. C. J . Am. Chem. Soc. 1975, 97, 6598.

5564 Organometallics, Vol. 18, No. 26, 1999
Meneghetti et al.
Ta ble 4. Selected Bon d Dista n ces (Å) a n d An gles
(d eg) for 13ba
Co-C(Cp) av
C-C(Cp) av
C-C(Ph) av
Co-P(1)
2.097(4)
1.392(8)
1.389(7)
2.236(1)
1.933(4)
2.038(3)
0.93(2)
P(1)-C(2)
P(1)-C(3)
C(9)-C(14)
C(14)-C(15)
C(15)-N
1.830(5)
1.817(4)
1.403(6)
1.495(6)
1.523(5)
1.495(5)
1.485(5)
Co-C(9)
Co-N
N-C(17)
Cpa-Co
N-C(18)
P(1)-C(1)
1.814(5)
P(1)-Co-C(9)
P(1)-Co-N
88.4(1)
101.08(9)
157.8(1)
114.5(5)
91.5(4)
112.9(2)
115.7(2)
119.9(1)
101.7(3)
101.7(2)
102.4(2)
84.2(1)
Co-C(9)-C(14)
C(9)-C(14)-C(15)
C(14)-C(15)-C(16)
C(14)-C(15)-N
C(16)-C(15)-N
Co-N-C(15)
113.6(3)
116.3(3)
115.3(3)
107.0(3)
115.2(3)
107.1(2)
111.5(2)
112.0(2)
109.0(3)
109.3(3)
108.0(3)
-71(2)
Cpa-Co-N
Cpa-Co-C(9)
Cpa-Co-P(1)
Co-P(1)-C(1)
Co-P(1)-C(2)
Co-P(1)-C(3)
C(1)-P(1)-C(2)
C(1)-P(1)-C(3)
C(2)-P(1)-C(3)
C(9)-Co-N
Co-N-C(17)
F igu r e 3. ORTEP view of the cationic part of 13b.
Co-N-C(18)
C(15)-N-C(17)
C(15)-N-C(18)
C(17)-N-C(18)
C(17)-N-Co-P(1)
(RCo,RC) and vice versa for 12b (RCo,SC) as compared to
12a ′ (SCo,RC).
As we have seen earlier, the iodide ligands in these
organocobalt compounds are readily substituted by a
phosphine ligand in the presence of PF6-. Thus, treating
12a ,a ′ with 1 equiv of PMe2Ph afforded a quantitative
a
Cpa represents the centroid of the cyclopentadienyl ring.
iodide by PMe2Ph has occurred with retention of con-
figuration. The conformation of the five-membered
chelate ring is the same as that found for 12a . A
selection of bond distances and angles is displayed in
Table 4.
1
yield of 13b,b′ (eq 7). The H as well as the 31P NMR
The 1H NMR spectum of the minor isomer 13b′ shows
an important downfield chemical shift for the benzylic
proton (∆δ ) 2.3 ppm) and a high-field shift for one of
the methyls of the NMe2 (∆δ ) 1.0 ppm). The latter
4
signal appeared additionally as a doublet due to J H-P
coupling with the phosphorus atom. Similar effects have
been observed for the minor isomer obtained with other
phosphines (see below). This latter result shed light
upon the likely conformation of the five-membered
chelate ring in 13b′. In this compound the configuration
at Co is opposite that in 13b and this leads to important
steric repulsion between the PMe2Ph ligand and the
benzylic methyl unit which are now closer to each other
than in the major isomer 13b (see Figure 3). Due to this
repulsion the methyl is forced into an equatorial position
with respect to the aryl ring, and this leads to a ring-
puckering conformation inverse to that unambiguously
established for 13b.30 As a consequence, one methyl
group of the NMe2 unit and the phosphorus atom of
PMe2Ph are in an almost eclipsed situation (see the
Newman projection in Scheme 2), and this is the reason
4
for the occurrence of the J H-P coupling constant that
spectra (see below) indicate that 13b:13b′ has been
obtained in a ratio of 19:1 (de ) 91%). This result clearly
indicated that the reaction proceeds without racemiza-
tion at the metal center.
To establish whether the substitution reaction has
taken place with retention or inversion of configuration
at the Co center, the crystal structure of this compound
has been determined (see Figure 3).
Assuming again that the crystal that has been used
for the X-ray diffraction is that of the major isomer,29 it
is at once apparent that the configuration at the cobalt
atom is the same as in 12a ; i.e., the substitution of the
has been found for one Me of the NMe2 group. Other
phosphine ligands, e.g. PMe3 and PPh2Me, may also be
used to substitute the iodide ligand in 12a ,a ′. With PMe3
we obtained 13a ,a ′ with a de of 75%, whereas with PPh2-
Me 13c,c′ was formed with a lower de. In this latter
case, however, we found that the formation of the minor
isomer 13c′ was under kinetic control. Indeed, after 17
h of reaction the formation of 13c,c′ occurred with a de
of ∼60% but, when 13c,c′ was allowed to slowly crystal-
lize, led to a quantitative formation of 13c, whereas no
13c′ could be detected at all, which is a strong indication
that the formation of the major isomer is controlled
thermodynamically.
(29) NOESY 1H NMR of 13b,b′ showed that the benzylic hydrogen
atom of the major isomer is in close proximity to both the methyl groups
and the ortho protons of the phenyl of PMe2Ph and, hence, the
configuration of the major isomer is indeed the same as that of the
crystal used for the X-ray structure determination.
(30) According to Figure 4 the major and minor diastereoisomers
have different ring puckering; however, they are labeled by the same
configuration, λ.

Optically Active Organocobalt Compounds
Organometallics, Vol. 18, No. 26, 1999 5565
Sch em e 2. Con for m a tion s of th e F ive-Mem ber ed
a
Ch ela te Rin g in 13b a n d 13b′
F igu r e 5. CD spectra of 13d ,d ′ and 13e,e′.
Ta ble 5. Selected 1H NMR Da ta (in p p m ) for
Ca tion ic Co Der iva tives
complexes
CHMe
N(CH3)2
∆δ
12a , 12b
12a ′, 12b′
13a
13a ′
13b
13b′
13c
13c′
13d
13d ′
13e
3.42
3.94
3.17
4.40
1.90
4.17
1.98
4.36
3.23
4.10
4.28
4.06
3.51 and 2.48
3.26 and 1.92
3.04 and 2.62
3.12 and 1.75a
2.81 and 2.40
3.01 and 1.38a
3.05 and 2.57
3.18 and 1.48a
2.94 and 2.51
3.03 and 1.84
2.84 and 2.42
n.o.b and 1.79
1.03
1.34
0.42
1.34
0.41
1.63
0.48
1.7
0.43
1.19
0.42
n.d.c
13e′
a
The high-field diastereotopic Me of the NMe2 unit is a doublet
due to J H-P coupling. n.o. ) not observed. c n.d. ) not deter-
mined.
2
b
1
Nevertheless, the analysis of the H NMR spectrum
of 13d ,d ′ allowed a rather safe determination of the
configuration at the metal center. As described earlier,
the 1H NMR spectra of the minor isomers show an
important downfield chemical shift for the benzylic
proton and a high-field shift for one of the methyls of
the NMe2 unit (see Table 5).
a
The Newman projections of the organocobalt compounds
are viewed along the Co-N axis.
The reactions for the synthesis of complexes related
to 13 were performed basically by abstraction of the iodo
ligand and replacement by the neutral ligands (PR3 and
CNtBu). Two basic mechanisms can be proposed for this
type of substitution reactions: dissociative and associa-
tive. It is generally accepted1,3,31-33 that substitution
reactions take place via a dissociative mechanism,
frequently with retention of the metal configuration.
The behavior of compounds 13c and 13c′ obtained with
the PPh2Me ligand suggests a specific behavior of this
ligand toward coordination to the cobalt atom with
respect to the other phosphines used in this study. It
appeared indeed that this ligand led to a mixture of
diastereoisomers whose ratio varied as a function of
time, evolving from a 60% to a >99% de after ca. 7 days.
We checked that this behavior was taking place in
solution (CDCl3) over the same period of time; i.e., the
isomerization of 13c′ to 13c was not due only to a solid-
state phenomenon whereby, for instance, 13c would
F igu r e 4. CD spectra of 13a ,a ′, 13b,b′, and 13c,c′.
The assignment of the same configuration at the Co
atom in the isomers 13a -c came from the comparison
of their CD spectra. Almost the same approach was
observed in their corresponding CD curves (see Figure
4).
The CD spectra of 13d ,d ′ and 13e,e′ appear to display
related features (see Figure 5). However, as the natures
of the ligands L are very different, an accurate analysis
based on their CD spectra is not advisable and the
determination of the configuration of the metal center
can afford erroneous results.12a
(31) Hofmann, P. Angew. Chem. 1977, 89, 551.
(32) Bogdanovic, Angew. Chem., Int. Ed. Engl. 1973, 12, 954.
Konowles, W. S.; Sabacky, M. J .; Vineyard, B. D.; Weinkauf, D. J . J .
Am. Chem. Soc. 1975, 97, 2567. Trost, B. M.; Runge, T. A. J . Am. Chem.
Soc. 1981, 103, 2485, 7550, 7559.
(33) Dewey, M. A.; Stark, G. A.; Gladysz, J . A. Organometallics 1996,
15, 4798.

5566 Organometallics, Vol. 18, No. 26, 1999
Meneghetti et al.
Sch em e 3
analogy exists between the structure of the resulting
cobalt(III) complexes and that of related ruthenium(II)
derivatives.14,34 This striking analogy is best emphasized
when studying the transmetalation of optically active
ligands, as this reaction afforded the same diastereo-
isomers with almost the same de. Moreover, both
compounds display the same configurational stability
at the Co and Ru center, as no epimerization could be
evidenced, with the important exception however of the
compound 13c′, derived from the coordination of PPh2-
Me on 12a . Some important differences exist, however,
between these two families of organometallic com-
pounds. Among these is the extraordinary chemical
stability in protic solvents of the cobalt derivatives,
whereas their ruthenium counterparts are markedly
less stable, as they usually lead rapidly to decomposition
products under these conditions.35
Exp er im en ta l Section
All reactions were performed in Schlenk flasks under
oxygen- and water-free nitrogen. Solvents were dried and
distilled under nitrogen: toluene over sodium and CH2Cl2 over
P2O5. IR spectra were recorded in KBr on a Bruker IFS-66.
The Service Central d’Analyse of Universite´ Louis Pasteur and
of Institut Charles Sadron (Strasbourg, France) performed the
elemental analyses. The 1H NMR spectra were recorded at
300.13 MHz, 13C NMR spectra at 75.47 MHz, and 31P NMR at
121.51 MHz on a FT-Bruker instruments (AC-300) and were
externally referenced to TMS. Chemical shifts (δ) and coupling
constant (J ) are expressed in ppm and Hz, respectively.
Circular dichroism spectra were recorded in CH2Cl2 on an ISA
J obin-Yvon CD6 instrument. UV-vis spectra were recorded
on a Perkin-Elmer Lambda 11 UV-vis spectrometer and are
reported over the range of ca. 200-800 nm. [R]D values were
measured at 20 °C on a Perkin-Elmer 341 polarimeter.
The starting materials [CpCoI2]2 (1)20 and lithiated tertiary
arylamines derivatives (N∧C-Li) were prepared according to
published methods.36,38
Syn t h eses. (η5-C5H 5)Co(C6H 4CH 2NMe2)I (3a ). [2-((Di-
methylamino)methyl)phenyl]lithium (2a ; 0.282 g, 2.00 mmol)
was slowly added to a stirred suspension of [CpCoI2]2 (1; 0.756
g, 1.00 mmol) in toluene (50 mL). The resulting green suspen-
sion was stirred for 16 h at room temperature, and all the
volatiles were removed in vacuo. The residue was extracted
with CH2Cl2 (100 mL) and filtered. The filtrate was washed
with water (5 × 10 mL). The organic phase was dried with
MgSO4, filtered, and concentrated in vacuo, giving 3a as a
green solid. Yield: 0.60 g (78%). Anal. Calcd for C14H17CoIN
(385.14): C, 43.66; H, 4.45; N, 3.64. Found: C, 43.87; H, 4.50;
N, 3.64. 1H NMR (CDCl3): δ 8.35 (d, Ar, 3J H-H ) 7.58), 7.19 (t,
crystallize faster than 13c′. The rate of this isomeriza-
tion was not dependent upon the concentration of free
ligand, as the presence of 1 equiv of PPh2Me per 13c
did not accelerate the process. We can therefore exclude
a mechanism through which the phosphine in excess
would substitute the phosphine already present at Co
via a SN2 type reaction. Thus, we can actually assume
that, for this particular phosphine, there should exist a
reverse reaction for the coordination of the phosphine
for the less abundant diastereomer 13c′ leading to a
decoordinated Co species. This latter should be in
equilibrium with the major isomer, thus leading to the
complete epimerization of the minor isomer, this process
being controlled thermodynamically. We therefore pro-
pose that the substitution reaction with PPh2Me takes
place according to the reaction pathway depicted in
Scheme 3.
Accordingly we can also assume that the other opti-
cally active cationic species studied here should not
epimerize once they have been formed. This particular
behavior might well be related to the large cone angle
of PPh2Me compared to that of the other phosphine
used, which would have as a consequence a rather weak
interaction of the phosphine with Co (note that the
bulkier PPh3 did not coordinate to Co). This should occur
especially in the minor isomer, for which there should
be much steric hindrance at the Co center because of
the presence of the benzylic methyl group in proximity
to the site of coordination of the phosphine, a situation
that is dramatically different in the other diastereomer.
3
3
1H, Ar, J H-H ) 7.12), 6.90 (t, 1H, Ar, J H-H ) 7.58), 6.82 (d,
3
1H, Ar, J H-H ) 7.12), 5.03 (s, 5H, C5H5), 3.52 and 2.96 (AB
spin system, 2H, CH2N, 2J H-H ) 13.20), 3.36 and 2.74 (2s, 6H,
NMe2). 13C{1H}NMR (CDCl3): δ 153.53, 149.38, 142.38, 126.23,
123.36, 121.98 (C6H4), 72.76 (CH2N), 57.57, 56.44 (NMe2).
All the compounds 3b-g were obtained by following a
similar procedure and workup.
(η5-C5H5)Co(4-CH3-C6H3CH2NMe2)I (3b). Compound 1
(0.756 g, 1.00 mmol) reacted with [2-((dimethylamino)methyl)-
4-methylphenyl]lithium (2b; 0.310 g, 2.00 mmol) to give 3b
(34) Attar, S.; Catalano, V. J .; Nelson, J . H. Organometallics 1996,
15, 2932. Gu¨l, N.; Nelson, J . H. Organometallics 1999, 18, 709. Hansen,
H. D.; Maitra, K.; Nelson, J . H. Inorg. Chem. 1999, 38, 2150.
(35) Pfeffer, M. Ritleng, V. Unpublished observations.
(36) J astrzebski, J . T. B. H.; van Koten, G. Inorg. Synth. 1988, 26,
150.
(37) Arlen, C.; Pfeffer, M.; Bars, O.; Grandjean, P. J . Chem. Soc.,
Dalton Trans. 1983, 1535.
(38) Lednicer, D.; Hauser, C. R. Org. Synth. 1960, 40, 31.
Con clu sion s
Several conclusions may be drawn from this investi-
gation. It is now clear that a large number of anionic
N-containing ligands can be transferred to Co(III),
forming a wealth of pseudotetrahedral compounds hav-
ing a cobalt atom as a stereogenic center. A very close

Optically Active Organocobalt Compounds
Organometallics, Vol. 18, No. 26, 1999 5567
as a green solid. Yield: 0.69 g (86%). Anal. Calcd for C15H19
-
(η5-C5H5)Co(C10H7NMe2)I (5). This complex was obtained
using a workup similar to that used for 3a . 1 (0.756 g, 1.00
mmol) reacts with [8-((dimethylamino)naphthyl]lithium34 (4;
0.318 g, 2.00 mmol) to give 5 as a green solid. Yield: 0.68 g
(81%). Anal. Calcd for C17H17CoIN (421.17): C, 48.48; H, 4.07;
CoIN (399.16): C, 45.14; H, 4.80; N, 3.51. Found: C, 46.71;
1
3
H, 5.03; N, 3.51. H NMR (CDCl3): δ 8.23 (d, 1H, Ar, J H-H
)
3
7.67), 7.06 (d, 1H, Ar, J H-H ) 7.67), 6.69 (s, 1H, Ar), 5.02 (s,
5H, C5H5), 3.48 and 2.91 (AB spin system, 2H, CH2N, 2J H-H
)
1
13.35), 3.37 and 2.73 (2 s, 6H, NMe2), 2.36 (s, 3H, Ar-CH3).
13C{1H} NMR (CDCl3): δ 149.18, 148.10, 141.97, 132.66,
127.38, 123.09, (C6H3), 85.46 (C5H5), 72.67 (CH2N), 57.56, 56.38
(NMe2), 20.65 (Ar-CH3).
N, 3.33. Found: C, 48.30; H, 4.10; N, 3.27. H NMR (CDCl3):
3
δ 8.40 (d, 1H, Ar, J H-H ) 10.35), 7.55-7.37 (m, 3H, Ar), 7.21
(t, 1H, Ar, 3J H-H ) 11.79), 7.00 (d, 1H, Ar, 3J H-H ) 11.43), 5.21
(s, 5H, C5H5), 3.97 and 3.17 (2s, 6H, NMe2). 13C{1H} NMR
(CDCl3): δ 156.77, 144.38, 139.82, 134.39, 132.77, 127.14,
126.37, 125.04, 121.16, 114.50 (C10H6), 86.26 (C5H5), 63.71 and
57.47 (NMe2).
(η5-C5H5)Co(5-CH3-C6H3CH2NMe2)I (3c). Compound 1
(0.756 g, 1.00 mmol) reacted with [2-((dimethylamino)methyl)-
5-methylphenyl]lithium (2c; 0.310 g, 2.00 mmol) to give 3c as
a green solid. Yield: 0.56 g (70%). Anal. Calcd for C15H19CoIN
(399.16): C, 45.14; H, 4.80; N, 3.51. Found: C, 46.40; H, 4.99;
[(η5-C5H 5)Co(C6H 4CH 2NMe2)(P Me2P h )]+P F 6 (6a ). Di-
-
methylphenylphosphine (0.17 mL, 1.20 mmol) was added to a
stirred solution of 3a (0.385 g, 1.00 mmol) in CH2Cl2 (10 mL)
at room temperature. The color of the solution turned from
green to red-brown. After 1 h the volatiles were removed in
vacuo, affording a red-brown solid. This crude product was
dissolved with water (50 mL) and filtered. To the red aqueous
solution was added KPF6(aq) in excess, affording a red
precipitate. After 15 min the precipitate thus obtained was
filtered and washed with water (10 mL) and hexane (30 mL).
6a was isolated as a red powder after crystallization in acetone/
hexane and drying in vacuo. Yield: 0.46 g (86%). Anal. Calcd
1
N, 3.52. H NMR (CDCl3): δ 8.17 (s, 1H, Ar), 6.72 (s, 2H, Ar),
5.03 (s, 5H, C5H5), 3.47 and 2.93 (AB spin system, 2H, CH2N,
2J H-H ) 13.34), 3.36 and 2.73 (2s, 6H, NMe2), 2.43 (s, 3H, Ar-
CH3). 13C{1H} NMR (CDCl3): δ 146.30, 143.15, 141.77, 135.45,
124.47, 121.61 (C6H3), 85.65 (C5H5), 72.54 (CH2N), 57.56, 56.38
(NMe2), 21.86 (Ar-CH3).
(η5-C5H5)Co(4-F -C6H3CH2NMe2)I (3d ). Compound 1 (0.756
g, 1.00 mmol) reacted with [2-((dimethylamino)methyl)-4-
fluorophenyl]lithium (2d ; 0.318 g, 2.00 mmol) to give 3d as a
green solid. Yield: 0.56 g (70%).Anal. Calcd for C14H16CoFIN
(403.13): C, 41.71; H, 4.00; N, 3.47. Found: C, 41.98; H, 3.99;
for
C22H28CoF6NP2 (541.35): C, 48.81; H, 5.21; N, 2.59.
1
3
N, 3.56. 1H NMR (CDCl3): δ 8.22 (dd, 1H, Ar, J H-F ) 8.30,
Found: C, 47.95; H, 5.25; N, 2.50. H NMR (AcD6): δ 7.95 (d,
3
3
3J H-H ) 6.00), 6.97 (apparent ddd, 1H, Ar, 3J H-F ) 8.80, 3J H-H
1H, Ar, J H-H ) 7.65) 7.48 (t, 1H, Ar, J H-H ) 7.32), 7.35-
3
4
3
4
7.05 (m, 6H, P(C6H5)), 6.70 (d, 1H, Ar, J H-H ) 7.32), 5.55 (s,
) 6.00, J H-H ) 2.70), 6.61 (dd, 1H, Ar, J H-F ) 9.51, J H-H
)
5H, C5H5), 2.82 and 2.15 (AB spin system, 2H, CH2N, J H-H
)
2.70), 5.03 (s, 5H, C5H5), 3.47 and 2.94 (AB spin system, 2H,
2
CH2N, J H-H ) 13.53), 3.37 and 2.73 (2s, 6H, NMe2). 13C{1H}
15.00), 2.81 and 2.79 (2s, 6H, NMe2), 2.35 and 1.79 (2d, 6H,
PMe2, 2J H-P ) 10.41). 31P{1H} NMR (AcD6): δ 11.69, (s, PMe2-
1
3
NMR (CDCl3): δ 161.49 (d, J C-F ) 239.42), 149.60 (d, J C-F
) 7.04), 144.49, 142.01 (d, J C-F ) 7.04), 112.98 (d, J C-F
18.78), 109.25 (d, J C-F ) 18.78) (C6H3), 85.36 (C5H5), 72.23
(CH2N), 57.36, 56.27 (NMe2).
Ph), -143.57 (septet, PF6, J P-F ) 707.00). 13C{1H} NMR
1
3
2
)
2
2
(AcD6): δ 150.52 (d, J C-P ) 43.31), 150.24, 143.79, 127.20,
124.72, 124.07 (C6H4), 134.51 (d, Ci, 1J C-P ) 39.37), 131.30 (d,
3
2
(η5-C5H5)Co(5-F -C6H3CH2NMe2)I (3e). Compound 1 (0.756
g, 1.00 mmol) reacted with [2-((dimethylamino)methyl)-5-
fluorophenyl]lithium (2e; 0.318 g, 2.00 mmol) to give 3e as a
green solid. Yield: 0.39 g (48%). Anal. Calcd for C14H16CoFIN
(403.13): C, 41.71; H, 4.00; N, 3.47. Found: C, 41.98; H, 3.99;
Cm, J P-C ) 7.87) 131.01, 129.05 (d, Co, J C-P ) 9.85) (PC6H5),
90.08 (C5H5), 71.85 (CH2N), 60.86 and 56.98 (NMe2), 17.53 (d,
2J C-P ) 27.56) and 16.97 (d, J C-P ) 37.40) (PMe2).
2
[(η5-C5H5)Co(C6H4CH2NMe2)(P P h 2Me)]+ P F 6- (6b). Com-
pound 3a (0.385 g, 1.00 mmol) reacted with PPh2Me (0.17 mL,
1.20 mmol) to give 6b as a red solid. Yield: 0.52 g (87%). Anal.
Calcd for C27H30CoF6NP2 (603.42): C, 53.74; H, 5.01; N, 2.32.
Found: C, 51.28; H, 4.85; N, 2.16. 1H NMR (AcD6): δ 8.12 (m,
3H, PPh2 and Ar), 7.71 (app br s, PPh2, 3H), 7.44 (t, 1H, Ar,
3
N, 3.56. 1H NMR (CDCl3): δ 8.01 (dd, 1H, Ar, J H-F ) 9.30,
3
4J H-H ) 2.19), 6.75 (t, 1H, Ar, J H-H ) 7.68), 6.58 (dt, 1H, Ar,
4
3J H-F ) 8.90, J H-F ) 2.37), 5.04 (s, 5H, C5H5) 3.48 and 2.94
(AB spin system, 2H, CH2N, 2J H-H ) 13.17), 3.34 and 2.73 (2s,
3
3J H-H ) 7.68), 7.34 (t, 1H, Ar, J H-H ) 7.68), 7.28-7.08 (m,
1
6H, NMe2). 13C{1H} NMR (CDCl3): δ 161.70, (d, J C-F
)
3
2
3H, PPh2), 6.79 (m, 2H, PPh2), 6.70 (d, 1H, Ar, J H-H ) 7.32),
248.06), 156.46, 144.59, 128.24 (d, J C-F ) 17.72), 122.01 (d,
3J C-F ) 7.88), 109.96 (d, J C-F ) 21.66) (C6H3), 85.76 (s, 5H,
2
5.57 (s, 5H, C5H5), 2.88 (app s, 6H, NMe2), 2.81 and 2.16 (AB
spin system, 2H, CH2N, 2J H-H ) 14.80), 2.14 (d, 3H, PMe, 2J H-P
) 9.69). 31P{1H} NMR (AcD6): δ 24.79 (s, PPh2Me), -143.53
C5H5), 72.17 (CH2N), 57.49, 56.36 (NMe2).
(η5-C5H5)Co(4-CH3O-C6H3CH2NMe2)I (3f). Compound 1
(0.756 g, 1.00 mmol) reacted with [2-((dimethylamino)methyl)-
4-methoxyphenyl]lithium (2f; 0.318 g, 2.00 mmol) to give 3f
as a green solid. Yield: 0.49 g (59%). Anal. Calcd for C15H19
CoINO (415.16): C, 43.40; H, 4.61; N, 3.37. Found: C, 43.43;
1
(septet, PF6, J P-F ) 707.00). 13C{1H} NMR (AcD6): δ 150.62,
2
150.02 (d, J C-P ) 34.17), 143.95, 145.82, 129.48, 126.89,
126.33 (C6H4), 92.23 (C5H5), 74.18 (CH2N), 63.34 and 60.24
-
2
(NMe2), 17.89 (d, PMe, J C-P ) 37.38).
[(η5-C5H5)Co(C6H4CH2NMe2)(P Me3)]+ P F 6 (6c). Com-
-
1
3
H, 4.67; N, 3.36. H NMR (CDCl3): δ 8.19 (d, 1H, Ar, J H-H
)
3
4
pound 3a (0.385 g, 1.00 mmol) reacted with PMe3 (1 M in
toluene, 1.2 mL, 1.20 mmol) to give 6c as a red solid. Yield:
0.42 g (87%). Anal. Calcd for C17H26CoF6NP2 (479.27): C, 42.60;
8.40), 6.88 (dd, 1H, Ar, J H-H ) 8.40, J H-H ) 2.76), 6.50 (d,
1H, Ar), 5.01 (s, 5H, C5H5), 3.77 (s, 3H, CH3O), 3.48 and 2.90
(AB spin system, 2H, CH2N, 2J H-H ) 13.35), 3.38 and 2.74 (2s,
6H, NMe2). 13C{1H} NMR (CDCl3): δ 157.30, 149.42, 141.80,
139.48, 112.25, 108.86, (C6H3), 85.19 (C5H5), 72.52 (CH2N),
57.41 and 56.26 (NMe2), 55.12 (CH3O).
1
H, 5.47; N, 2.92. Found: C, 43.69; H, 5.51; N, 2.90. H NMR
3
4
(AcD6): δ 7.76 (apparent ddd, 1H, Ar, J H-H ) 7.47, J H-P
)
)
4
3
4
2.37, J H-H ) 1.11), 7.14 (td, 1H, Ar, J H-H ) 7.47, J H-H
3
4
(η5-C5H5)Co(5-CH3O-C6H3CH2NMe2)I (3g). Compound 1
(0.756 g, 1.00 mmol) reacted with [2-((dimethylamino)methyl)-
5-methoxyphenyl]lithium (2g; 0.318 g, 2.00 mmol) to give 3g
as a green solid. Yield: 0.03 g (4%). Anal. Calcd for C15H19
CoINO (415.16): C, 43.40; H, 4.61; N, 3.37. Found: C, 43.48;
1.47), 7.06 (tt, 1H, Ar, J H-H ) 7.32, J H-H ) 1.11), 6.99 (dd,
3
4
3
1H, Ar, J H-H ) 7.32, J H-H ) 1.47), 5.48 (d, 5H, C5H5, J H-P
2
) 0.90), 3.40 and 3.35 (AB spin system, 2H, CH2N, J H-H
)
16.26), 2.90 and 2.88 (2s, 6H, NMe2), 1.56 (d, 9H, PMe3, 2J H-P
) 10.59). 31P{1H} NMR (AcD6): δ 8.80 (s, PMe3), -143.53
-
(septet, PF6, J P-F ) 707.00). 13C{1H} NMR (AcD6): δ 151.27
1
1
4
H, 4.72; N, 3.46. H NMR (CDCl3): δ 7.90 (d, 1H, Ar, J H-H
)
)
2
2.37), 6.73 (d, 1H, Ar, 3J H-H ) 8.04), 6.46 (dd, 1H, Ar, 3J H-H
(d, J C-P ) 39.38), 149.64, 142.89, 127.34, 124.63, 123.50
(C6H4), 89.91 (C5H5), 73.21 (CH2N), 61.05, 57.77 (NMe2), 17.20
4
8.04, J H-H ) 2.37), 5.02 (s, 5H, C5H5), 3.89 (s, 3H, CH3O),
3.46 and 2.92 (AB spin system, 2H, CH2N, 2J H-H ) 12.96), 3.34
and 2.72 (2s, 6H, NMe2). 13C{1H} NMR (CDCl3): δ 156.77,
155.12, 141.59, 128.33, 121.77, 107.89 (C6H3), 85.67 (C5H5),
72.11 (CH2N), 57.46, 56.33 (NMe2), 55.26 (CH3O).
2
(d, PMe, J C-P ) 29.53).
[(η5-C5H5)Co(C6H4CH2NMe2)[P (OMe)3]+ P F 6- (6d ). This
complex was obtained using a workup similar to that used for
6a ; however, the reaction time was 7 h. 3a (0.385 g, 1.00 mmol)

5568 Organometallics, Vol. 18, No. 26, 1999
Meneghetti et al.
reacts with P(OMe)3 (0.14 mL, 1.20 mmol) to give 6d as a red
solid. Yield: 0.38 g (72%). Anal. Calcd for C17H26CoF6NO3P2
(527.27): C, 38.73; H, 4.97; N, 2.66. Found: C, 39.04; H, 5.04;
NMR (AcD6): major isomer, δ 11.64 (s, PMe3), -143.57 (septet,
1
PF6, J P-F ) 706.99). 13C{1H} NMR (AcD6): major isomer, δ
99.75, 95.99, 73.65, 68.88, 65.81 (C5H3), 89.05 (C5H5-Co), 70.28
3
b
N, 2.66. 1H NMR (AcD6): δ 7.75 (d, 1H, Ar, J H-H ) 6.39),
(C5H5-Fe), 62.75 (CH2NMe2), 60.98 (NCH3a), 59.75 (d, NCH3
,
1
7.13-7.00 (m, 3H, Ar), 5.53 (s, 5H, C5H5), 3.77 (d, 9H, OMe,
3J H-P ) 10.59), 3.65 (A part of an AB spin system, 1H, CHa Hb,
2J H-H ) 13.11), 3.30 (B part of the AB spin system, CHaHbN,
3J C-P ) 4.20), 17.07 (d, PMe3, J C-P ) 29.46).
(η5-C5H 5)Co[C6H 4CH 2NMe(E t )]I (10). [2-((Ethylmethyl-
amino)methyl)phenyl]lithium (9; 0.310 g, 2.00 mmol) was
slowly added to a stirred suspension of 1 (0.756 g, 1.00 mmol)
in toluene (50 mL). The resulting green suspension was stirred
for 16 h at room temperature, and all the volatiles were
removed in vacuo. The residue was extracted with CH2Cl2 (100
mL) and filtered. The filtrate was washed with water (5 × 10
mL). The organic phase was dried with MgSO4, filtered, and
concentrated in vacuo, giving 10 as a green solid. Yield: 0.17
g (21%). de ) 63%. Anal. Calcd for C15H19CoIN (399.16): C,
3J H-P ) 1.26), 2.88 and 2.82 (2s, 6H, NMe2). 31P{1H} NMR
1
(AcD6): δ 135.00 (s, P(OMe)3), -143.80 (septet, PF6, J P-F
)
)
2
712.08). 13C{1H} NMR (AcD6): δ 150.45, 146.35 (d, J C-P
21.62), 144.57, 126.69, 124.91, 123.65 (C6H4), 90.63 (C5H5),
73.12 (CH2N), 60.52 (P(OMe)3), 57.15 and 55.35 (NMe2).
[(η5-C5H5)Co(C6H4CH2NMe2)[P O(OMe)2] (6e). P(OMe)3
(0.14 mL, 1.20 mmol) was added to a stirred solution of 3a
(0.385 g, 1.00 mmol) in CH2Cl2 (10 mL) at room temperature.
After 6 h the solution turned from green to red. After 17 h the
volatiles were removed in vacuo, affording a red oily solid. This
crude product was recrystallized in CH2Cl2/hexane and dried
in vacuo; 6e was isolated as a light red powder. Yield: 0.25 g
(87%). Anal. Calcd for C16H23CoF6NO3P2 (512.25): C, 52.33;
H, 6.31; N, 3.81. Found: C, 52.33; H, 6.32; N, 3.78. IR (KBr):
1151 cm-1 (vs, νPdO) and 1040 and 993 cm-1 (doublet vs, νP-O).
1H NMR (AcD6): δ 7.60 (d, 1H,Ar, 3J H-H ) 7.50), 7.00 (td, 1H,
Ar, 3J H-H ) 7.50, 4J H-H ) 1.26), 6.94 (td, 1H, Ar, 3J H-H ) 7.11,
4J H-H ) 1.29), 6.82 (d, 1H, Ar, 3J H-H ) 7.11), 4.98 (s, 5H, C5H5),
4.28 (A part of an AB spin system, 1H, CHa Hb, 2J H-H ) 13.50),
2.71 (B part of the AB spin system, 1H, CHaHbN, 3J H-P ) 1.83),
3.41 and 3.30 (2d, 6H, PO(OMe)2, 2J H-P ) 10.23), 2.76 and 2.67
(2s, 6H, NMe2). 31P{1H} NMR (AcD6): δ 0.94.85 (s, PO(OMe)2),
1
45.14; H, 4.80; N, 3.51. Found: C, 45.99; H, 4.77; N, 3.57. H
NMR (CDCl3): major isomer, δ 8.37 (d, Ar, 3J H-H ) 7.68), 7.20
3
3
(t, 1H, Ar, J H-H ) 7.11), 6.90 (t, 1H, Ar, J H-H ) 7.32), 6.82
3
(d, 1H, Ar, J H-H ) 7.14), 5.03 (s, 5H, C5H5), 4.27 and 2.86
2
3
(ABX3 spin system, 2 dt, 2H, NCH2CH3, J H-H ) 13.71, J H-H
) 7.11), 3.35 and 3.08 (AB spin system, 2H, ArCH2N, 2J H-H
)
13.17), 2.70 (s, 3H, NMe), 1.22 (t, 3H, NCH2CH3); minor
3
isomer, δ 8.44 (d, Ar, J H-H ) 7.68), 5.02 (s, 5H, C5H5), 3.45
2
and 3.29 (AB spin system, 2H, ArCH2N, J H-H ) 13.68), 3.12
(s, 3H, NMe), 1.13 (t, 3H, NCH2CH3, J H-H ) 7.11). 13C{1H}
3
NMR (CDCl3): major isomer, δ 154.09, 150.69, 142.57, 125.69,
122.95, 121.89 (C6H4), 86.00 (C5H5), 68.39 (ArCH2N), 61.86
(NCH2CH3), 50.35 (NMe), 9.14 (NCH2CH3); minor isomer, δ
143.23, 121.30 (C6H4), 86.00 (C5H5), 66.40 (ArCH2N), 59.44
(NCH2CH3), 52.69 (NMe), 10.20 (NCH2CH3).
1
-143.80 (septet, PF6, J P-F ) 712.08). 13C{1H} NMR (AcD6):
2
(RCo,RC)-(η5-C5H5)Co(C6H4CH(Me)NMe2)I (12a ,a ′). [(R)-
2-(1-(Dimethylamino)ethyl)phenyl]lithium (11a ; 0.310 g, 2.00
mmol) was slowly added to a stirred suspension of 1 (0.756 g,
1.00 mmol) in toluene (50 mL). The resulting green suspension
was stirred for 16 h at room temperature, and all the volatiles
were removed in vacuo. The residue was extracted with CH2-
Cl2 (100 mL) and the extract filtered. The filtrate was washed
with water (5 × 10 mL). The organic phase was dried with
MgSO4, filtered, and concentrated in vacuo, giving 12a ,a ′ as
a green solid. Yield: 0.32 g (79%). de ) 91%. Anal. Calcd for
δ 152.129 (d, 1H, Ar, J C-P ) 49.29), 149.84, 143.93, 125.34,
123.07, 121.76 (C6H4), 88.45 (C5H5), 72.05 (CH2N), 60.61 and
2
56.48 (NMe2), 51.65 and 50.54 (2d, PO(OMe)2, J C-P ) 9.39).
-
[(η5-C5H5)Co(C6H4CH2NMe2)(CNtBu )]+P F 6 (6f). This
complex was obtained using a workup similar to that used for
6a ; however, the reaction time was 3 h. 3a (0.385 g, 1.00 mmol)
reacts with CNtBu (0.14 mL, 1.20 mmol), giving 6f as a red
solid. Yield: 0.230 g (47%). Anal. Calcd for C19H26CoF6N2P
(486.34): C, 46.93; H, 5.39; N, 5.76. Found: C, 46.78; H, 5.34;
1
N, 5.50. IR (Nujol): 2188 cm-1 (vs, νCtN). H NMR (CDCl3): δ
C
15H19CoIN (399.16): C, 45.14; H, 4.80; N, 3.51. Found: C,
7.50 (d, 1H, Ar), 7.26-6.98 (m, 3H, Ar), 5.33 (s, 5H, C5H5),
3.65 and 3.36 (AB spin system, 2H, CH2N, 2J H-H ) 14.08), 2.82
and 2.53 (2s, 6H, NMe2), 1.43 (s, 9H, tBu). 13C{1H} NMR
(CDCl3): δ 149.75, 147.23, 141.40, 127.56, 124.68 (C6H4), 91.62
(CtN), 89.65 (C5H5), 74.31 (CH2N), 60.31 (C(CH3)3), 57.78 and
56.98 (NMe2), 29.71 (C(CH3)3).
45.83; H, 4.89; N, 3.47. UV-vis (CH2Cl2): λmax 242 nm (log
ꢀmax 0.94). 1H NMR (CDCl3): major isomer, δ 8.44 (d, Ar, 3J H-H
) 7.47), 7.22 (t, 1H, Ar, 3J H-H ) 7.50), 6.90 (t, 1H, Ar, 3J H-H
)
3
7.47), 6.67 (d, 1H, Ar, J H-H ) 7.50), 5.05 (s, 5H, C5H5), 3.51
and 2.48 (2s, 6H, NMe2), 3.42 (q, 1H, CH(Me)N, 3J H-H ) 6.75),
3
[(η5-C5H 5)Co(η5-C5H 5)F e (η5-C5H 3)CH 2NMe 2(P Me 3)]+-
1.12 (d, 3H, CH(Me)N); minor isomer, δ 8.53 (d, Ar, J H-H
)
)
3
3
P F 6- (8). n-Butyllithium (l.5 M in hexane; 3.6 mL, 5.5 mmol)
7.32), 7.35 (t, 1H, Ar, J H-H ) 7.36), 7.03 (t, 1H, Ar, J H-H
3
35
7.35), 6.74 (d, 1H, Ar, J H-H ) 7.47), 5.05 (s, 5H, C5H5), 3.94
(q, 1H, CH(Me)N, 3J H-H ) 6.57), 3.26 and 1.92 (2s, 6H, NMe2),
1.12 (d, 3H, CH(Me)N). 13C{1H} NMR (CDCl3): major isomer,
δ 153.07, 152.81, 142.06, 126.39, 123.44, 123.05 (C6H4), 86.24-
(C5H5), 69.40 (CH(Me)N), 54.34, 47.95 (NMe2), 9.50(CH(Me)N);
minor isomer, δ 86.99 (C5H5).
was slowly added to a stirred suspension of CpFeCpCH2NMe2
(1.0 mL, 5.0 mmol) in Et2O (10 mL). After 1 h the volatiles
were removed in vacuo and an orange oily solid was isolated.
The residue was dissolved in toluene (40 mL) and cooled to
-78 °C, and 1 (1.511 g, 2.00 mmol) was added. The reaction
temperature was increased to room temperature and left for
30 min. Trimethylphosphine (1 M in toluene; 4.2 mL, 4.2
mmol) was added. After 2 h the volatiles were removed in
vacuo, water (50 mL) was added, and the mixture was stirred
for 30 min. The red-brown mixture was filtered, and the
residue was washed with water (2 × 20 mL). To the combined
aqueous solutions was added KPF6 in excess. The red precipi-
tate thus formed was filtered and washed with water (10 mL)
and hexane. The crude product was purified by chromatogra-
phy on silica gel CH2Cl2/MeOH (95:5), recrystallized in acetone/
hexane, and dried in vacuo, giving 8 as a red solid. Yield: 0.30
All the compounds 13 were obtained following a similar
procedure and workup.
(S C o ,R C )-[(η5-C 5H 5)C o (C 6H 4C H (Me )N Me 2)(P Me 3)]+-
-
P F 6 (13a ,a ′). Trimethylphosphine (1 M in toluene; 1.2 mL,
1.2 mmol) reacted with 12a ,a ′ (0.399 g, 1.00 mmol) to give
13a ,a ′ as a red solid. Yield: 0.42 g (86%). de ) 75%. Anal.
Calcd for C18H28CoF6NP2 (493.31): C, 43.83; H, 5.72; N, 2.84.
Found: C, 43.97; H, 5.79; N, 2.76. UV-vis (CH2Cl2): λmax 241
nm (log ꢀmax 0.58). 1H NMR (CDCl3): major isomer, δ 7.85 (ddd,
3
4
4
1H, Ar, J H-H ) 7.29, J H-P ) 2.37, J H-H ) 1.44), 7.21-7.07
3
5
4
g
(13%); de
>
99%. Anal. Calcd for
C
21H30CoF6FeNP2
(m, 2H, Ar), 6.87 (ddd, J H-H ) 7.32, J H-P ) 2.73, J H-H )
(587.20): C, 42.92; H, 5.15; N, 2.39. Found: C, 39.96; H, 4.67;
1.30), 5.50 (d, 5H, C5H5, 3J H-P ) 0.72), 3.17 (q, 1H, CH(Me)N,
3J H-H ) 6.57), 3.04 and 2.62 (2s, 6H, NMe2), 1.53 (d, 9H, PMe3,
2J H-P ) 10.59), 1.28 (d, 3H, CH(Me)N); minor isomer, δ 7.61
1
N, 2.12. H NMR (AcD6): δ 5.53 (s, 5H, C5H5-Co), 4.66 (app
3
s, 1H, C5H3), 4.51 (t, 1H, C5H3, J H-H ) 2.19), 4.36 (s, 5H,
3
3
3
C5H5-Fe), 4.11 (d, 1H, C5H3, J H-H ) 1.83), 3.51 and 2.90 (2
(app d, 1H, Ar, J H-H ) 7.11), 6.95 (app d, 1H, Ar, J H-H )
s, 6H, NMe2), 2.82 (AB spin system, 2H, CH2N, 2J H-H ) 15.18),
6.93), 5.43 (d, 5H, C5H5, 3J H-P ) 0.90), 4.40 (q, 1H, CH(Me)N,
3J H-H ) 6.75), 3.12 and 1.75 (s and d, 6H, NMe2, 4J H-P ) 3.09),
1.41 (d, 9H, PMe3, J H-H ) 10.77). 31P{1H}
2

Optically Active Organocobalt Compounds
Organometallics, Vol. 18, No. 26, 1999 5569
1.66 (d, 9H, PMe3, 2J H-P ) 10.41), 1.30 (d, 3H, CH(Me)N). 31P-
{1H} NMR (CDCl3): major isomer, δ 6.40 (s, PMe3), -143.57
(septet, PF6, 1J P-F ) 707.00); minor isomer, δ 10.00 (s, PMe3),
minor isomer (CDCl3), δ 152.51, 142.10, 128.39, 125.15 (C6H4),
89.46 (C5H5), 75.72 (CH(Me)N), 55.60, 46.42 (NMe2), 13.44 (d,
1J C-P ) 31.50) (PMe), 10.08 (CH(Me)N).
1
-143.57 (septet, PF6, J P-F ) 707.00). 13C{1H} NMR (CDCl3):
( S C o ,R C ) -[ ( η5 -C 5 H 5 ) C o ( C 6 H 4 C H ( M e ) N M e 2 ) ( C N t -
Bu )]+P F 6- (13d ,d ′). tert-Butyl isocyanide (0.14 mL, 1.20 mmol)
was added to a stirred solution of 12a ,a ′ (0.399 g, 1.00 mmol)
in CH2Cl2 (10 mL) at room temperature. The solution turned
from green to light red. After 4 h the volatiles were removed
in vacuo, affording a light red solid. This crude product was
dissolved in water (50 mL) and filtered. To the red aqueous
solution was added KPF6(aq) in excess, affording a red
precipitate. After 15 min the product thus obtained was filtered
and washed with water (10 mL) and hexane (30 mL). After
recrystallization in acetone/hexane and drying in vacuo 13d ,d ′
was isolated as a red powder. Yield: 0.41 g (82%). de ) 55%.
Anal. Calcd for C20H28CoF6N2P (500.36): C, 48.01; H, 5.64; N,
5.60. Found: C, 47.88; H, 5.79; N, 5.48. UV-vis (CH2Cl2): λmax
2
major isomer, δ 152.97, 152.27 (d, J C-P ) 24.03), 142.62,
127.53, 124.77, 124.77 (C6H4), 90.50 (C5H5), 71.59 (CH(Me)N),
55.03, 51.34 (NMe2), 17.50 (d, PMe3, 1J C-P ) 50.82), 10.44 (CH-
(Me)N); minor isomer, δ 152.54, 141.40, 127.95 (C6H4), 89.05
(C5H5), 75.22 (CH(Me)N), 55.31, 47.36 (NMe2), 16.80 (d, 1J C-P
) 50.80), 9.68 (NMe2).
(S C o ,R C )-[(η5 -C 5 H 5 )C o (C 6 H 4 C H (M e )N M e 2 )(P M e 2 -
P h )]+P F 6- (13b,b′). Dimethylphenylphosphine (0.17 mL, 1.20
mmol) was added to a stirred solution of 12a ,a ′ (0.399 g, 1.00
mmol) in CH2Cl2 (10 mL) at room temperature. The solution
turned from green to red-brown. After 1 h the volatiles were
removed in vacuo, affording a red-brown solid. This crude
product was dissolved in water (50 mL) and filtered. To the
red aqueous solution was added KPF6(aq) in excess, affording
a red precipitate. After 15 min the precipitate thus obtained
was filtered and washed with water (10 mL) and hexane (30
mL). After recrystallization in acetone/hexane and drying in
vacuo, 13b,b′ was isolated as a red powder. Yield: 0.43 g
(77%). de ) 91%. Anal. Calcd for C23H30CoF6NP2 (555.37): C,
49.74; H, 5.44; N, 2.52. Found: C, 49.85; H, 5.46; N, 2.52. UV-
vis (CH2Cl2): λmax 246 nm (log ꢀmax 0.62). 1H NMR (CDCl3):
1
225 nm (log ꢀmax 0.60). IR (KBr): 2194 cm-1 (νs CtN). H NMR
(CDCl3): major isomer, δ 7.58 (dd, 1H, Ar, 3J H-H ) 7.32, 4J H-H
) 1.47), 7.12 (m, 2H, Ar), 6.85 (dd, 1H, Ar, 3J H-H ) 7.05, 4J H-H
3
) 0.99), 5.37 (s, 5H, C5H5), 3.23 (q, 1H, CH(Me)N, J H-H
)
6.84), 2.94 and 2.51 (2s, 6H, NMe2), 1.30 (s, 9H, CNtBu), 1.29
3
(d, 3H, CH(Me)N); minor isomer, δ 7.47 (dd, 1H, Ar, J H-H
)
7.08, 4J H-H ) 1.98), 6.88 (app d, 1H, Ar, 3J H-H ) 7.08), 5.30 (s,
5H, C5H5), 4.10 (q, 1H, CH(Me)N, 3J H-H ) 6.84), 3.03 and 1.84
(2 s, 6H, NMe2). 13C{1H} NMR (CDCl3): major isomer, δ
151.24, 149.34, 141.25, 127.92, 125.16, 124.42 (C6H4), 90.64
(C5H5), 73.27 (CH(Me)N), 60.67 (C(CH3)3), 56.08, 49.94 (NMe2),
29.91 (C(CH3)3), 12.32 (CH(Me)N); minor isomer (CDCl3), δ
152.63, 141.49, 128.05, 124.76 (C6H4), 89.52 (C5H5), 75.75 (CH-
(Me)N), 60.15 (C(CH3)3), 55.29, 47.62 (NMe2), 30.41 (C(CH3)3),
10.35 (CH(Me)N).
3
4
major isomer, δ 7.78 (app ddd, 1H, Ar, J H-H ) 8.58, J H-P
)
)
4
3
5
2.37, J H-H ) 1.11), 7.35 (tdd, 1H, Ar, J H-H ) 6.86, J H-P
4
1.83, J H-H ) 1.11), 7.31-7.19 (m, 3H, P(C6H5)), 7.12 (t, 1H,
3
3
Ar, J H-H ) 7.29), 6.84 (m, 2H, P(C6H5)), 6.51 (dd, 1H, J H-H
4
3
) 7.47, J H-H ) 1.08), 5.22 (d, 5H, C5H5, J H-P ) 0.75), 2.81
and 2.40 (2s, 6H, NMe2), 2.13 and 1.74 (2d, 6H, PMe2, 2J H-P
)
3
9.66), 1.90 (q, 1H, CH(Me)N, J H-H ) 6.57), 0.81 (d, 3H, CH-
(Me)N); minor isomer, δ 5.24 (d, 5H, C5H5, 3J H-P ) 0.54), 4.17
3
(SCo,RC)-[(η5-C5H 5)Co(C6H 4CH (Me)NMe2)(P O(OMe)2)]
(13e,e′). Trimethyl phosphite (0.14 mL, 1.2 mmol) was added
to a stirred solution of 12a ,a ′ (0.399 g, 1.00 mmol) in CH2Cl2
(10 mL) at room temperature. The solution turned from green
to red-brown. After 18 h the volatiles were removed in vacuo,
affording a red solid. This crude product was dissolved with
CH2Cl2 (5.0 mL), recrystallized with hexane, and dried in
vacuo, affording 13e,e′ as a red powder. Yield: 0.21 g (55%).
de ) 91%. Anal. Calcd for C17H25CoNO3P (381.30): C, 53.55;
H, 6.61; N, 3.67. Found: C, 52.81; H, 6.49; N, 3.51. UV-vis
(CH2Cl2): λmax 225 nm (log ꢀmax 0.80). IR (KBr): 1154 and 1124
cm-1 (νs,PdO), 1042 and 997 cm-1 (νs,P-O). 1H NMR (CDCl3):
(q, 1H, CH(Me)N, J H-H ) 6.57), 3.01 and 1.38 (s and d, 6H,
NMe2, J H-P ) 3.15), 1.23 (d, 3H, CH(Me)N). 31P{1H} NMR
4
(CDCl3): major isomer, δ 7.99 (s, PMe2Ph), -144.29 (septet,
1
PF6, J P-F ) 712.08); minor isomer, δ 18.29 (s, PMe2Ph),
-144.29 (septet, PF6, J P-F ) 712.08). 13C{1H} NMR (CDCl3):
1
2
major isomer, δ 152.64, 150.38 (d, J C-P ) 56.90), 143.07,
1
130.70, 127.57, 124.94 (C6H4), 134.94 (d, Ci, J C-P ) 61.84),
3
2
130.64, 130.39 (d, Cm, J C-P ) 9.90), 128.88 (d, Co, J C-P
)
14.84) (PC6H5), 90.14 (C5H5), 69.74 (CH(Me)N), 54.40 (d, 3J C-P
2
) 4.95) 54.40 and 51.35 (NMe2), 17.69 (d, J C-P ) 54.43) and
17.60 (d, 2J C-P ) 42.06) (PMe2), 9.85 (CH(Me)N); minor isomer,
δ 88.85 (C5H5).
(S C o ,R C )-[(η5 -C 5 H 5 )C o (C 6 H 4 C H (M e )N M e 2 )(P P h 2 -
3
major isomer, δ 7.65 (d, 1H, Ar, J H-H ) 6.75), 7.10-6.95 (m,
Me)]+P F 6 (13c,c′). Diphenylmethylphosphine (0.17 mL, 1.2
-
2H, Ar), 6.67 (d, 1H, Ar, 3J H-H ) 6.75), 4.99 (s, 5H, C5H5), 4.28
3
mmol) reacts with 12a ,a ′ (0.399 g, 1.00 mmol) to give 13c,c′
as a red solid. Yield: 0.34 g (55%). de ) 60% and de > 99%
after slow recrystallization in acetone/hexane. Anal. Calcd for
(q, 1H, CH(Me)N, J H-H ) 6.93), 3.45 and 2.25 (2d, 6H,
3
P(OMe)2, J H-P ) 10.23), 2.84 and 2.42 (2s, 6H, NMe2), 1.11
3
(d, 3H, CH(Me)N); minor isomer, δ 7.71 (d, 1H, Ar, J H-H
)
C
28H32CoF6NP2 (617.45): C, 54.47; H, 5.22; N, 2.27. Found:
7.14), 4.93 (s, 5H, C5H5), 4.06 (q, 1H, CH(Me)N, 3J H-H ) 6.75),
1.79 (s, 3H, NMe), 1.20 (d, 3H, CH(Me)N). 31P{1H} NMR
(CDCl3): major isomer, δ 65.64 (s, PO(OMe)2). 13C{1H} NMR
C, 54.26; H, 5.00; N, 2.25. UV-vis (CH2Cl2): λmax 223 nm (log
ꢀmax 0.70). 1H NMR (AcD6): major isomer, δ 8.23 (ddd, 1H, Ar,
3J H-H ) 7.65, 4J H-P ) 2.58, 4J H-H ) 1.11), 8.14-6.75 (m, 12H,
2
(CDCl3): major isomer, δ 153.20, 152.80 (d, J C-P ) 53.16),
3
4
Ar and PPh2), 6.58 (dd, 1H, Ar, J H-H )7.47, J H-H ) 1.29)
143.52, 125.26, 123.02, 122.55 (C6H4), 88.87 (C5H5), 67.87 (CH-
5.56 (d, 5H, C5H5, 3J P-H ) 0.54) 3.05 and 2.57 (2s, 6H, NMe2),
(Me)N), 53.02, 51.18 (NMe2), 51.52 and 50.09 (2 d, 6H,
3
2
1.98 (q, 1H, CH(Me)N, J H-H ) 6.75) 2.10 (d, 3H, PMe, J H-P
) 9.66) 0.85 (d, 3H, CH(Me)N); minor isomer, δ 7.97 (d, 1H,
2
2
P(OMe)2, J C-P ) 7.88 and J C-P ) 9.84), 9.41 (CH(Me)N);
minor isomer, δ 143.16, 125.89 (C6H4), 87.67 (C5H5), 74.71 (CH-
(Me)N), 55.12, 45.83 (NMe2), 9.85 (CH(Me)N).
3
3
Ar, J H-H ) 6.78), 7.00 (d, 1H, Ar, J H-H ) 7.47), 5.31 (d, 5H,
C5H5, 3J H-P ) 0.57), 4.36 (q, 1H, CH(Me)N, 3J H-H ) 6.7z), 3.18
2
X-r a y Exp er im en ts. Collection of th e X-r a y Da ta a n d
Str u ctu r e Deter m in a tion for 12a a n d 13b. For both
structures, data were collected on a Nonius KappaCCD dif-
fractometer using Mo KR graphite-monochromated radiation
(λ ) 0.7107 Å). The structures were solved using direct
methods and refined against |F|. Hydrogen atoms were intro-
duced as fixed contributors at their calculated positions (dC-H
) 0.95 Å, BH ) 1.3Bequiv for the carbon to which it was
attached). For both structures, all non-hydrogen atoms were
refined anisotropically. Absorption corrections are integrated
in the scaling procedure. For all computations the Nonius
(s, 3H, NMe), 1.82 (d, 3H, PMe, J H-P ) 9.87), 1.48 (d, 3H,
NMe, J H-P ) 3.30), 1.28 (d, 3H, CH(Me)N). 31P{1H} NMR
4
(AcD6): major isomer, δ 22.27 (s, PPh2Me), -143.48 (septet,
1
PF6, J P-F ) 701.91); minor isomer, δ 30.60 (s, PPh2Me),
-143.48 (septet, PF6, J P-F ) 701.91). 13C{1H} NMR (AcD6):
1
2
major isomer, δ 153.80, 151.19 (d, J C-P ) 35.78), 143.71,
127.81, 125.64, 125.19 (C6H4), 134.30 (d, 1J C-P ) 39.99), 133.60
2
1
3
(d, J C-P ) 10.52), 133.57 (d, J C-P ) 40.00), 132.80 (d, J C-P
2
) 8.41), 131.97, 131.10, 129.61 (d, J C-P ) 10.52), 128.85 (d,
3J C-P ) 10.52) (PPh2), 90.86 (C5H5), 70.34 (CH(Me)N), 55.70,
51.52 (NMe2), 15.98 (d, 2J C-P ) 37.88) (PMe), 5.46 (CH(Me)N);

5570 Organometallics, Vol. 18, No. 26, 1999
Meneghetti et al.
OpenMoleN package39 was used. The absolute structures were
determined by refining Flack’s x parameters. Table 4 contains
X-ray data collection partameters and final results.
a ) 8.2523(1) Å, b ) 12.4052(3) Å, c ) 27.5552(6) Å, V ) 2820.9
(2) Å3, Z ) 4, Dc ) 1.44 g cm-3, µ(Mo KR) ) 0.776 mm-1; total
of 15 575 reflections was collected, 2.5° < θ < 26.29°; 3916
unique reflections having I >3σ(I); 334 parameters. Final
results: R(F) ) 0.037, Rw(F) ) 0.055, GOF ) 1.187, maximum
Cr ysta l d a ta for 12a : dark green crystals, data collected
at -100 °C (crystal dimensions 0.20 × 0.20 × 0.20 mm3);
residual electronic density 0.674 e Å-3
.
C
15H19NCoI, Mr ) 399.16, orthorhombic, space group P212121,
a ) 7.0212(1) Å, b ) 14.2383(3) Å, c ) 14.7569(3) Å, V )
1475.25(8) Å3, Z ) 4, Dc ) 1.80 g cm-3, µ(Mo KR) ) 3.215
mm-1; total of 12 992 reflections, 2.5° < θ < 29.58°; 3203
unique parameters. Final results: R(F) ) 0.046, Rw(F) ) 0.064,
GOF ) 1.370, maximum residual electronic density 0.962 e
Ack n ow led gm en t. The support of this research by
the CAPES-COFECUB (Project No. 188/96) and the
Universite´ Louis Pasteur is gratefully acknowledged.
Å-3
.
Su p p or tin g In for m a tion Ava ila ble: Tables of crystal-
lographic data, atomic coordinates, anisotropic thermal pa-
rameters, bond lengths and angles, and hydrogen atom
parameters for 12a and 13b. This material is available free
of charge via the Internet at http://pubs.acs.org.
Cr ysta l Da ta for 13b: red crystals, data collected at -100
°C (crystal dimensions 0.20 × 0.14 × 0.11 mm3); C26H36
-
NOF6P2Co, Mr ) 613.45, orthorhombic, space group P212121,
(39) OpenMoleN, Interactive Structure Solution; Nonius BV, Delft,
The Netherlands, 1997.
OM990517N