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Introduction of an Optically Active Ligand into Transition Metal Complexes with Five Independent Ligands.

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MgSO, and distilled I0.897 g, crude product (25%), b.p.
= 100" (bath temp.)/lO torr]. Redistillation afforded chemically pure (R)-(
+)-(3)having [a], = 3.43 (c= 8.4, C6H6)
corresponding to 16% enantiomeric excessr41.
+
Received: September 8, 1980 [ Z 758 IE]
German version: Angew. Chem. 93,481 (1981)
CAS Registry numbers:
@-(-)-1, 77495-38-6; (2). 77495-39-7; R
(J
( +)-3, 3082-64-2; P h C H d H Z ,
100-42-5; BrCCI,, 75-62-7; [( -)-dioplRhCI, 61 113-00-6
The reaction of bromotrichloromethane with styrene in
2 :1 ethanol-benzene, in the presence of an optically active
phosphane-rhodium complex [(-)-diop]RhClf3I (0.30
mmol) at 80°C for 18 h, gave the 1 :1-adduct ( I ) in 26%
yield. The adduct (1) showed an optical rotation of
[a],= -22.5 ( C = 10.7, C6H6) which corresponded to > 32%
enantiomeric excess and (4-configuration.
The enantiomeric excess and the absolute configuration
were determined in the following way using a sample of ( I )
with [a],= - 11.3" (c= 10.3, C6&) obtained in a separate
run. This sample was treated with an excess of NaN, to
give the azide (2), which was not isolated but directly re+)-1-phenyl-1-propylamine(3)
duced with LiAIH, to (R)-(
which showed [a],=
3.43 ( C ~ 8 . 4 , C6H.5) and corresponded to an optical purity of 16%l4].Thus, the adduct
(?+(-)-(I) with
-22.5 corresponds to >32% enantiomeric excess. It should be noted that the optical purity
must be much higher than 32%, since SN2 displacement of
(I) with NaN, may involve partial racemizati~n[~].
+
Since various transition metal catalysts for addition of
organic halides to olefins are knownf6]and a variety of chiral ligands are now available"', the present result opens up
new possibilities for asymmetric synthesis.
Experimental
(4-(-)-(I): To a solution of styrene (9.36 g, 90 mmol)
and BrCCI, (4.46 g, 22.5 mmol) in EtOH (30 cm') was added a solution of [( -)-diop]RhClL3], prepared from
[RhC1(C8H14)2]171
(0.108 g, 0.30 mmol) and ( -)-diopI3]
(0.164 g, 0.33 mmol) in benzene (15 cm') under N,. The
mixture was heated under reflux for 18 h: the color of the
mixture changed from green to dark brown after 30 min.
Concentration and distillation gave (3-(
- ) - ( I ) (1.78 g,
26% yield), b. p. 87-91 "C/0.6 torr''].
Conversion (1)-+(3): A sample of (1) (8.51 g, 28.2 mmol)
with [a]D= - 11.3 (c= 10.3, C6H6), which was obtained in a
separate run, was added to a solution of NaN3 (4.29 g, 66
mmol) in 162 cm3 of EtOH/H,O (4 :1). The mixture was
heated for 36 h at 50 "C, cooled, and treated with H 2 0 (75
cm'), nBu20 (100 cm3), and 40% aqueous CaCI2 solution
(125 cm3) to separate the organic layer. The aqueous layer
was extracted with nBu20 (3 x 50 cm'). After drying over
MgS04, the combined nBu,O solution containing the azide
(2) was added dropwise to a suspension of LiAIH4 (16 g,
420 mmol) in nBuzO at 15 "C. The mixture was heated for
15 h at lOO"C, cooled, and made acidic with 4~ HCl. The
aqueous layer was washed with Et,O (2 x 40 cm')), made alkaline with conc. aqueous KOH, heated to 100°C to dissolve the inorganic salts and after cooling extracted with
Et,O (4x 100 cm3). The ethereal solution was dried over
476
0 Verlag Chemie GmbH, 6940 Weinheim, 1981
111 H. B. Kagan. J. C. Fiaud, Top. Stereochem. 10, 175 (1978).
I21 G. Berti. A. Marsili, Tetrahedron 25, 4515 (1969), reported asymmetric
bromination of olefins in the presence of cinchona alkaloids, which were
used in almost stoichiometric amounts; B. Bouteuin, E. B. Dongla, Tetrahedron Lett. 1977,4315, described FeCI,-catalyzed addition of CCl. to an
optically active olefin, (-)-menthy1 acrylate.
131 H. B. Kagan. T. P. Dang, J. Am. Chem. SOC.94, 6429 (1972).
I41 The highest value of optical rotation for (R)-(+)-(3) reported is
[&= +21.7 (CsH6), K . Harada. 1. Oh-hashi, Bull. Chem. Sac. Jpn. 43,
960 (1970).
[51 Reaction of I-chloro-1-phenylethane with NaN, in 8Wh EtOH has been
reported to proceed with 30% racemization; F. Hiron. E. D. Hughes, J.
Chem. SOC.1960,795.
I61 F. Minisci. Acc. Chem. Res. 8, 165 (1975); J . K. Kochi: Organometallic
Mechanism and Catalysis, Academic Press, New York 1978, Ch. 6 and
8.
[71 L. Porn, A. Lionerli, G. Allegro. A . Immini, Chem. Commun. 1965, 336.
181 B.p.=92"C/O.2 torr; M. S. Kharasch, 0. Reinmuth, W.H. U r y , J. Am.
Chem. SOC.69, 1105 (1947).
Introduction of an Optically Active Ligand into
Transition Metal Complexes with Five Independent
Ligands
By Ernest0 Colomer, Robert J. P. Corriu, and
Andrk Vioux['l
Recently, we reported the introduction of an optically
active triorganogermyl ligand at a transition metal site, by
displacement of a CO-ligand"]. This reaction allowed us to
synthesize the optically active anion (3), which was isolated as the tetraethylammonium salt (36) (Table I), from
the (R)-enantioner of the germyllithium compound (I) and
the tricarbonylmanganese complex (2). It is assumed that
the reaction proceeds with retention of configuration at
germanium, since optically active germyllithium compounds are known to react with retention of configuration
in substitution reactions[21.The anion (3) reacts with methyl
iodide affording the neutral complex (4), whose crystal
i
c'
"'c0
I
6)
- (3)
Np = , l - N a p h t h y l
['I Prof. Dr. R. J. D. Comu, Dr. E. Colomer, Dr. Ing. A. Vioux
Laboratoire des Organometalliques,
Equipe de Recherche associee au C.N.R.S. No. 554,
Universite des Sciences et Techniques du Languedoc
Place Eugene Bataillon, F-34060 Montpellier-Cedex (France)
0570-0833/81/0505-476 $ 02.50/0
Angew. Chem. Inr. Ed. Engl. 20 (1981) No. 5
In the benzyl derivative (lUa) the -CH,-protons
are
non-equivalent ( J = 10 Hz) since there is a chiral center at
molybdenum[81.
structure has not yet been determined. It is well known,
however, that complexes with five ligands, one of which is
a cyclopentadienyl moiety, have a square pyramidal geometry with the cyclopentadienyl moiety occupying the apical
p ~ s i t i o n ' ~from
] ; the IR spectrum, only the diug- (or tmns)
isomer-both CO-ligands are arranged diugonaUfoalwas obtained"] (Table 1).
Table 1. Selected physical data of the novel complexes.
Complex
[a1
(3b) [bl
(4) [fl
(601
(W
M.p. I T 1
W O
~0
'H-NMR
(6-values rel. to TMS)
CSHS
M-CH
1850s
1775 s
1960 m
1905 s
1970m
1910 s
1964m
-
-Id,
-
- [g. h]
0.99
-
- [g. i]
0.97
-
- [g, i]
3.36
1970m
1910 s
-
- [g, i]
0.97
77-79
1970m
-
- [g, i]
3.40
172-1 75
190-192
124-125
114-115
141-142
1911 s
1845s
1835s
2010 s
2005 s
2000 s
1525s
1515s
1645 s
1650 s
1640 s
5.00[d]
5.13 [dl
4.80 [g]
4.63 [g]
4.77 [g]
-
59-60
(53-55) [c]
112-113
(109-110) [c]
133-134
96-98
IR [cm-'1
(CHzCI2)
el
(7), M
=
(S), M
=
Mo
W
RX = CH31, C6H5CH2Br
-
0
I
1906 s
1%
(64
(7)
(81
(9ai
iW
iIW
121-1 22
-
0.74
2.80, 3.27
0.80
These type of complexes are surprizingly-as the 'HNMR spectra (in [D,}dimethyl sulfoxide) show-stable up
to 100°C and no isomerization occurs (the compounds decompose first above 120 "C, but without isomeri~ation)~~~.
Complexes with five independent and different ligands
are, at present, the subject of much interest['o1,since they
offer the possibility of synthesizing novel, stable, optically
active transition metal compounds.
[a] All compounds gave satisfactoly elemental analyses. @I (5')-isomer
([alg= -3.9, CHzC12); crystallizes with one molecule CH2C12.[c] Melting
point of the racemate. [d] In CD2C12.[el CSH4two multiplets at 6=3.87 and
4.04; C,H,CH,, 6=1.80; GeCH,, 6=0.70. [fl (9-isomer ([u]g=+7.2
(C,H,), + 18.7 (CH2CIZ)).&] In C6D6.[h] CsH4, two multiplets at 6=3.63 and
3.87. CsH,CH, and GeCH,, 6= 1.33. [i] CsH4, two multiplets at 6 = 3 . 8 and
4.1; CSH,CH3, 6-1.3.
Experimental
The triphenylgermanyl and triphenylsilyl substituted anions, (5~)"'and (5b) respectively, were analogously alkylated with methyl iodide and benzyl bromide to the dicarbonylmanganese complexes (6). The 'H-NMR spectrum
only showed signals corresponding to the diag-isomer: the
benzyl derivatives show a single sharp signal for the CH2group, i. e. the two protons-as expected for the diug-isomer-are magnetically equivalent (Table 1).
All reactions are carried out under an N2-atmosphere. In
a typical experiment 326 mg (0.5 mmol) of (7)in 15 cm3 tetrahydrofuran is treated with an excess of CH31 at room
temperature. The initial brown solution becomes yellow
and a precipitate of Et4NI is formed. After 15 min, the solvent is removed, the residue treated with toluene and filtered. The solution is concentrated to ca. 10 cm3, 10 cm3
hexane added and the mixture left at -20°C. Yellow crystals of ( 9 4 are obtained (157 mg, yield 58%).
Received: March 17, 1980 [Z 757a IE]
German version: Angew. Chem. 93, 488 (1981)
(Sa), M = S i
[Sh), M = Ge
R X = CH31, C & C H 2 B r
( 6 a ) , M = Si, R = CH3
(6b), M = S i , R = CHzC6Hs
~
.
( 6 c ) , M = G e , R = CH3
( 6 d ) , M = G e , R = CH2C6H5
The alkylation of the anionic molybdenum and tungsten
complexes (7) or (8)@],
respectively, can lead to the formation of three enantiomeric pairsI'I. Reaction of (7) with methyl iodide produced the three enantiomeric pairs (9u)(9c) in yields of 66, 14 and 19%, respectively (determined
by 'H-NMR spectroscopy); the pure isomer ( 9 4 could be
obtained in 58% yield by fractional crystallization (Table
1). Its structure was established by IR spectroscopy (Table
1). Isomers (96) and ( 9 4 were not isolated ('H-NMR:
6=4.80 and 0.27 or 4.47 and 0.37 respectively; IR:
vco= 1925 and vNo=1645 cm-').
Angew. Chem. Inr. Ed. Engl. 20 (1981) No. 5
-
[I] E. Colomer, R. J. P. Corriu, J. Chem. SOC.Chem. Commun. 1978, 435. '
[2] A . G. Brook, G.J. D. Peddle, J. Am. Chem. SOC.85, 2338 (1963); C. Eaborn, R . E. E. Hill, P. Simpson, J. Organomet. Chem. 15, PI (1968); ibid.
37, 267, 275 (1972); F. Carre. R. Corriu. ibid. 65. 349 (1974).
131 K . W. Barnetf, D. W . Slocurn, J. Organomet. Chem. 44, l(1972).
[4] A. R. Manning, J. Chem. SOC.A 1967, 1984; W. Jetz, W . A. G. Graham,
Inorg. Chem. 10, 1647 (1971).
151 E. Colomer, R. 1. P. Corriu. A . Vioux, Inorg. Chem. 18, 695 (1979).
[6] The complexes (7) and (8)were prepared as described in [l] by treatment
of (qS-CsH~)Mo(CO),NOor ($-CSHS)W(CO)2N0 with LiGePhl at
-78°C.
(71 H. Bnmner, Chem. Unserer Zeit 1, 157 (1977).
181 If. Bnmner, E . Schmidt, Angew. Chem. 81, 570 (1969); Angew. Chem.
Int. Ed. Engl. 8, 616 (1969).
[91 Cf. G. M. Reisner. I. Bernal, H. Bnmner. M. Muschiol, B. Siebrecht, J.
Chem. SOC.Chem. Comrnun. 1978, 691; P. I . van Yliet, M . Kokkes, G.
van Koten, K . Vrieze, J. Organomet. Chem. 187, 413 (1980); Y. Shoo, J.
Am. Chem. SOC.102, 5396 (1981).
[lo] a) R. B. King, R. H. Reimann, Inorg. Chem. 15,179 (1976); b) N. J . Couille, M.0.Albers. J. Organomet. Chem. 172, C 1 (1979); A . G. Ginzburg,
V. N . Setkina. D. N . Kursanou, ibid. 182, C 1 (1979).
D Verlag Chemie GmbH, 6940 Weinheim, 1981
OS70-0833/81/0SOS-477$ 02.50/0
477
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