An Approach to Heterometallic Complexes with Selenolate and Tellurolate Ligands: Crystal Structures of cis-[Mn(CO)4(SePh)2] -,[(CO)3Mn(μ-SeMe)3Mn(CO)3] -,(CO)4Mn(μ-TePh)2Co(CO)(μ-SePh) 3Mn(CO)3, and (CO)3Mn(μ-SePh)3 Fe(CO)3

Article abstract of DOI:10.1021/ic951487t

Oxidative addition of diorganyl diselenides to the coordinatively unsaturated, low-valent transition-metal-carbonyl fragment [Mn(CO)₅]^- produced cis-[Mn(CO)₄(SeR)₂]^-. The complex cis-[PPN][Mn(CO)₄(SePh)₂] crystallized in triclinic space group P1? with a = 10.892(8) ?, b = 10.992(7) ?, c = 27.021(4) ?, α = 101.93(4)°, β = 89.79(5)°, γ = 116.94(5)°, V = 2807(3) ?³, and Z = 2; final R = 0.085 and R_w = 0.094. Thermolytic transformation of cis-[Mn(CO)₄(SeMe)₂]^- to [(CO)³Mn(μ-SeMe)₃Mn(CO)₃]^- was accomplished in high yield in THF at room temperature. Crystal data for [Na-18-crown-6-ether][(CO)₃Mn(μ-SeMe)₃Mn(CO) ₃]: trigonal space group R3?, a = 13.533(3) ?, c = 32.292(8) ?, V = 5122(2) ?³, Z = 6, R = 0.042, R_w = 0.041. Oxidation of Co²⁺ to Co³⁺ by diphenyl diselenide in the presence of chelating metallo ligands cis-[Mn(CO)₄(SePh)₂]^- and cis-[Mn(CO)₄(TePh)₂]^-, followed by a bezenselenolate ligand rearranging to bridge two metals and a labile carbonyl shift from Mn to Co, led directly to [(CO)₄Mn(μ-TePh)₂Co(CO)(μ-SePh) ₃Mn(CO)₃]. Crystal data: triclinic space group P1?, a = 11.712(3) ?, b = 12.197(3) ?, c = 15.754(3) ?, α = 83.56(2)°, β = 76.13(2)°, γ = 72.69(2)°, V = 2083.8(7) ?³, Z = 2, R = 0.040, R_w = 0.040. Addition of fac-[Fe(CO)₃(SePh)₃]^- to fac-[Mn(CO)₃(CH₃CN)₃]⁺ resulted in formation of (CO)₃Mn(μ-SePh)₃Fe(CO)₃. This neutral heterometallic complex crystallized in monoclinic space group P2₁/n with a = 8.707(2) ?, b = 17.413(4) ?, c = 17.541(4) ?, β = 99.72(2)°, V = 2621(1) ?³, and Z = 4; final R = 0.033 and R_w = 0.030.

Full text of DOI:10.1021/ic951487t

2530
Inorg. Chem. 1996, 35, 2530-2537
An Approach to Heterometallic Complexes with Selenolate and Tellurolate Ligands: Crystal
Structures of cis-[Mn(CO)4(SePh)2]-, [(CO)3Mn(µ-SeMe)3Mn(CO)3]-,
(CO)4Mn(µ-TePh)2Co(CO)(µ-SePh)3Mn(CO)3, and (CO)3Mn(µ-SePh)3Fe(CO)3
Wen-Feng Liaw,*,† Chih-Yuan Chuang,† Way-Zen Lee,† Chen-Kang Lee,†
Gene-Hsiang Lee,‡ and Shie-Ming Peng‡
Departments of Chemistry, National Changhua University of Education, Changhua, Taiwan 50058,
ROC, and National Taiwan University, Taipei, Taiwan 10764, ROC
ReceiVed NoVember 20, 1995X
Oxidative addition of diorganyl diselenides to the coordinatively unsaturated, low-valent transition-metal-carbonyl
fragment [Mn(CO)5]- produced cis-[Mn(CO)4(SeR)2]-. The complex cis-[PPN][Mn(CO)4(SePh)2] crystallized
in triclinic space group P1h with a ) 10.892(8) Å, b ) 10.992(7) Å, c ) 27.021(4) Å, R ) 101.93(4)°, â )
89.79(5)°, γ ) 116.94(5)°, V ) 2807(3) Å3, and Z ) 2; final R ) 0.085 and Rw ) 0.094. Thermolytic
transformation of cis-[Mn(CO)4(SeMe)2]- to [(CO)3Mn(µ-SeMe)3Mn(CO)3]- was accomplished in high yield in
THF at room temperature. Crystal data for [Na-18-crown-6-ether][(CO)3Mn(µ-SeMe)3Mn(CO)3]: trigonal space
group R3h, a ) 13.533(3) Å, c ) 32.292(8) Å, V ) 5122(2) Å3, Z ) 6, R ) 0.042, Rw ) 0.041. Oxidation of
Co2+ to Co3+ by diphenyl diselenide in the presence of chelating metallo ligands cis-[Mn(CO)4(SePh)2]- and
cis-[Mn(CO)4(TePh)2]-, followed by a bezenselenolate ligand rearranging to bridge two metals and a labile carbonyl
shift from Mn to Co, led directly to [(CO)4Mn(µ-TePh)2Co(CO)(µ-SePh)3Mn(CO)3]. Crystal data: triclinic space
group P1h, a ) 11.712(3) Å, b ) 12.197(3) Å, c ) 15.754(3) Å, R ) 83.56(2)°, â ) 76.13(2)°, γ ) 72.69(2)°,
V ) 2083.8(7) Å3, Z ) 2, R ) 0.040, Rw ) 0.040. Addition of fac-[Fe(CO)3(SePh)3]- to fac-[Mn(CO)3(CH3-
CN)3]+ resulted in formation of (CO)3Mn(µ-SePh)3Fe(CO)3. This neutral heterometallic complex crystallized in
monoclinic space group P21/n with a ) 8.707(2) Å, b ) 17.413(4) Å, c ) 17.541(4) Å, â ) 99.72(2)°, V )
2621(1) Å3, and Z ) 4; final R ) 0.033 and Rw ) 0.030.
Introduction
or transmetalation between an alkali-metal selenolate and a metal
halide,4 insertion,5 nucleophilic cleavage of the E-E (E ) Se,
Te) bonds by metal hydrides,1 and the oxidation of metal upon
reaction with the diorganyl dichalcogenides.1,2,6
Recent work in this laboratory has focused on the syntheses
and characterizations of novel metal tellurolate and selenolate
complexes via activation of diorganyl dichalcogenides (oxidative
addition/nucleophilic displacement) to anionic metallic frag-
ments. Application of anionic metallic fragments for preparation
of metal tellurolates/selenolates has been proved to be one of
the most versatile routes and to be particularly suitable for d8
anionic metal carbonyls ([HFe(CO)4]-, [REFe(CO)4]- (E ) Se,
Te; R ) Ph, alkyl), [Mn(CO)5]-, [Re(CO)5]-).1,2 There have
been many reports relevant to the syntheses of metal selenolate
and tellurolate complexes. Synthetic approaches, to our knowl-
edge, involve the protolysis including reaction of alkylmetal/
metal amido complexes with selenol/tellurol,3 the metathesis
Interest in metal chalcogenolates stems not only from their
potential use as precursors for M/Se materials7 but also from
the perspective of reactivity. In particular, the use of the
complexes cis-[Mn(CO)4(ER)2]- and fac-[Fe(CO)3(EPh)3]- (E
) Se, Te) is of further interest because they contain sites of
latent reactivity, the delocalized lone pairs of electrons around
chalcogen atoms, which may react with other organometallic
moieties to form heterometallic chalcogenolate species. In our
continued work on transition-metal chalcogenolates, we have
concentrated our attention on the development of heterometallic
chalcogenolate species and a synthetic route to new metal-
chalcogenolate species employing cis-[Mn(CO)4(ER)2]- and fac-
[Fe(CO)3(EPh)3]- as chelating ligands and intermetal ligand
transfer reagents.
† National Changhua University of Education.
‡ National Taiwan University.
X Abstract published in AdVance ACS Abstracts, March 15, 1996.
(1) (a) Liaw, W.-F.; Chiang, M.-H.; Liu, C.-J.; Harn, P.-J.; Liu, L.-K.
Inorg. Chem. 1993, 32, 1536. (b) Liaw, W.-F.; Lai, C.-H.; Lee, C.-
K.; Lee, G.-H.; Peng, S.-M. J. Chem. Soc., Dalton Trans. 1993, 2421.
(c) Liaw, W.-F.; Lai, C.-H.; Chiang, M.-H.; Hsieh, C.-K.; Lee, G.-
H.; Peng, S.-M. J. Chin. Chem. Soc. (Taipei) 1993, 40, 437. (d) Liaw,
W.-F.; Ou, D.-S.; Horng, Y.-C.; Lai, C.-H.; Lee, G.-H.; Peng, S.-M.
Inorg. Chem. 1994, 33, 2495. (e) Liaw, W.-F.; Chiou, S.-J.; Lee, W.-
Z.; Lee, G.-H.; Peng, S.-M. J. Chin. Chem. Soc. (Taipei) 1993, 40,
361.
In this paper it is shown that the anionic [Mn(CO)5]- is
effective in activating the Se-Se bond of diorganyl diselenides
and that cis-[Mn(CO)4(ER)2]- and fac-[Fe(CO)3(SePh)3]- are
potential “chelating metallo ligands” in the syntheses of
(4) (a) Kersting, B.; Krebs, B. Inorg. Chem. 1994, 33, 3886. (b) Berardini,
M.; Emge, T.; Brennan, J. G. J. Am. Chem. Soc. 1993, 115, 8501.
(c) Ruhlandt-Senge, K.; Davis, K.; Dalal, S.; Englich, U.; Senge, M.
O. Inorg. Chem. 1995, 34, 2587.
(5) (a) Eikens, W.; Kienitz, C.; Jones, P. G.; Tho¨ne, C. J. Chem. Soc.
Dalton Trans. 1994, 3329. (b) Christuk, C. C.; Ibers, J. A. Inorg.
Chem. 1993, 32, 5105.
(6) (a) Brewer, M.; Khasnis, D.; Buretea, M.; Berardini, M.; Emge, T. J.;
Brennan, J. G. Inorg. Chem. 1994, 33, 2743. (b) Lee, J.; Brewer, M.;
Berardini, M.; Brennan, J. G. Inorg. Chem. 1995, 34, 3215.
(7) (a) Kanatzidis, M. G.; Huang, S. Coord. Chem. ReV. 1994, 130, 509.
(b) Brennan, J. G.; Siegrist, T.; Carroll, P. J.; Stuczynski, S. M.; Brus,
L. E.; Steigerwald, M. L. J. Am. Chem. Soc. 1989, 111, 4141.
(2) Liaw, W.-F.; Ou, D.-S.; Li, Y.-S.; Lee, W.-Z.; Chuang, C.-Y.; Lee,
Y.-P.; Lee, G.-H.; Peng, S.-M. Inorg. Chem. 1995, 34, 3747.
(3) (a) Cary, D. R.; Ball, G. E.; Arnold, J. J. Am. Chem. Soc. 1995, 117,
3492. (b) Bochmann, M.; Powell, A. K.; Song, X. J. Chem. Soc.,
Dalton Trans. 1995, 1645. (c) Ellison, J. J.; Ruhlandt-Senge, K.; Hope,
H. H.; Power, P. P. Inorg. Chem. 1995, 34, 49. (d) Ruhlandt-Senge,
K.; Power, P. P. Inorg. Chem. 1993, 32, 3478. (e) Gindelberger, D.
E.; Arnold, J. Inorg. Chem. 1994, 33, 6293. (f) Ruhlandt-Senge, K.
Inorg. Chem. 1995, 34, 3499. (g) Strzelecki, A. R.; Likar, C. L.;
Helsel, B. A.; Utz, T.; Lin, M. C.; Bianconi, P. A. Inorg. Chem. 1994,
33, 5188. (h) Cary, D. R.; Arnold, J. Inorg. Chem. 1994, 33, 1791.
0020-1669/96/1335-2530$12.00/0 © 1996 American Chemical Society

Complexes with Selenolate and Tellurolate Ligands
Inorganic Chemistry, Vol. 35, No. 9, 1996 2531
Addition of [Na-18-crown-6-ether][Mn(CO)5] and (MeSe)2. [Na-
18-crown-6-ether][Mn(CO)5] (0.5 mmol, 0.291 g)8 and (MeSe)2 (0.094
g, 0.5 mmol) dissolved in 10 mL of THF were stirred under nitrogen
at ambient temperature. A vigorous reaction occurred immediately with
evolution of CO gas. The reaction was monitored with FTIR constantly.
heterometallic chalcogenolates. Specifically, the syntheses and
characterizations of the novel cis-[Mn(CO)4(SePh)2]-, 1, the
triply-bridged selenolate complex [(CO)3Mn(µ-SeMe)3Mn-
(CO)3]-, 2, and a heterometallic Mn(I)-Co(III)-Mn(I) mixed-
chalcogenolate complex (CO)4Mn(µ-TePh)2Co(CO)(µ-SePh)3Mn-
(CO)3, 3, from reduction of diphenyl diselenide by Co2+ in the
presence of chelating metallo ligands cis-[Mn(CO)4(EPh)2]- (E
) Se, Te) are described. In addition, the synthesis and structure
of the isolobal species (CO)3Mn(µ-SePh)3Fe(CO)3, 4, are
reported. Also, we provide more mechanistic information about
the formation of cis-[Mn(CO)4(SeR)2]-.
The IR spectrum, νCO (THF) 2031 m, 1960 vs, 1938 m, 1894 m cm-1
,
having the same pattern as but differing slightly in position from that
of cis-[Mn(CO)4(SePh)2]-, indicated the formation of cis-[Mn(CO)4-
(SeMe)2]-. 1H NMR (CD3CN): δ 1.53 (s) ppm (CH3) for cis-[Na-18-
crown-6-ether][Mn(CO)4(SeMe)2]. The reaction mixture was stirred
for 1 h at room temperature; the IR spectrum showed two new bands
attributed to carbonyl stretching modes (νCO (THF) 1969 vs, 1886 vs
cm-1) of [Na-18-crown-6-ether][(CO)3Mn(µ-SeMe)3Mn(CO)3]. The
reaction solution was stirred at room temperature for 5 h; the IR
spectrum revealed that all cis-[Mn(CO)4(SeMe)2]- had completely
converted to [Na-18-crown-6-ether][(CO)3Mn(µ-SeMe)3Mn(CO)3]. The
reaction mixture was reduced to 5 mL under vacuum, and diethyl ether
(5 mL) was added. The solution was then filtered to remove [Na-18-
crown-6-ether][MeSe]. The orange-brown solution was layered with
hexane; storage for 3 weeks at -10 °C led to formation of orange-
brown crystals of [Na-18-crown-6-ether][(CO)3Mn(µ-SeMe)3Mn(CO)3]
suitable for X-ray crystallography. 1H NMR (CD3CN): δ 1.75 (CH3)
Experimental Section
Manipulations, transfers, and reactions of samples were conducted
under nitrogen according to standard Schlenk techniques or in a
glovebox (Ar gas). Solvents were distilled under nitrogen from
appropriate drying agents (diethyl ether from CaH2; acetonitrile from
CaH2/P2O5; hexane and tetrahydrofuran (THF) from Na/benzophenone)
and stored in dried, N2-filled flasks over 4 Å molecular sieves.
A
nitrogen purge was used on these solvents before use, and transfers to
reaction vessels were via stainless-steel cannula under N2 at a positive
pressure. The reagents manganese decacarbonyl, 18-crown-6-ether,
tellurium powder, diphenyl diselenide, bis(triphenylphosphoranylidene)-
ammonium chloride, phenylmagnesium bromide, dimethyl diselenide,
iron pentacarbonyl, and cobalt perchlorate (Aldrich) were used as
received. Infrared spectra were recorded on a spectrometer (Bio-Rad
FTS-7 FTIR) with sealed solution cells (0.1 mm) and KBr windows.
In NMR spectra (recorded on a Bruker AC 200 spectrometer), chemical
shifts of 1H and 13C are relative to tetramethylsilane. UV-visible
spectra were recorded on a GBC 918 spectrophotometer. Gas chro-
matography was carried out on a Varian 3300 using a Shimadzu RC-
6A integrator. Analyses made use of a flame ionizing detector (FID);
(satellite J H- Se ) 8.6 Hz), 3.6 (s) ppm (18-crown-6-ether). 13C NMR
(CD3CN): δ 26.2 (s) ppm (CH3). IR (νCO) (THF): 1969 s, 1886 vs
1
77
cm-1
.
Preparation of (CO)3Mn(µ-SePh)3Co(CO)(µ-TePh)2Mn(CO)4.
The reaction mixture, cis-[PPN][Mn(CO)4(SePh)2] (0.204 g, 0.2 mmol)
and cis-[PPN][Mn(CO)4(TePh)2] (0.223 g, 0.2 mmol), was added to
Co(ClO4)2‚6H2O (73.2 mg, 0.2 mmol) and (PhSe)2 (41 mg, 0.1 mmol)
in THF solution. After 10 min of stirring at room temperature, the
solvent was removed at reduced pressure. The residue was dissolved
in 35 mL of diethyl ether at 0 °C, and the dark purple solution was
filtered to remove [PPN][ClO4]. The filtrate (in diethyl ether) was
stored in a refrigerator (-10 °C) for 3 weeks to induce precipitation of
dark purple crystals of (CO)3Mn(µ-SePh)3Co(CO)(µ-TePh)2Mn(CO)4;
yield 0.228 g (90%). IR (νCO) (THF): 2063 w, 2027 sh, 2007 vs, 1988
nitrogen was the carrier gas, the column was OV-17 (5%) on
1
Chromosorb W, 80/100 mesh, 6 ft ×
/ in. stainless steel tubing.
8
Analyses of carbon, hydrogen, and nitrogen were obtained with a CHN
analyzer (Heraeus).
m, 1959 w, 1928 m cm-1 1H NMR (C4D8O): δ 6.95-8.24 (m) ppm
.
Preparation of cis-[PPN][Mn(CO)4(SePh)2]. [PPN][Mn(CO)5] (0.5
mmol, 0.367 g)8 dissolved in THF (5 mL) was stirred under N2, and
diphenyl diselenide (0.5 mmol, 0.156 g) in THF solution was added to
the [PPN][Mn(CO)5] solution by cannula under positive N2 gas at room
temperature. A vigorous reaction occurred immediately with evolution
of CO gas. After stirring of the reaction solution for 0.5 h, the volume
of the solution was reduced to 3 mL and an orange-yellow product
precipitated on addition of hexane (20 mL) at 0 °C. The product was
isolated by removing the solvent and recrystallized from THF-hexane
under CO atmosphere. The yield was 0.48 g (95%) of an orange-
yellow solid cis-[PPN][Mn(CO)4(SePh)2]. The orange-yellow solution
was layered with hexane under CO atmosphere; storage for 4 weeks at
-10 °C led to formation of orange-yellow crystals cis-[PPN][Mn(CO)4-
(SePh)2] suitable for X-ray crystallography. IR (νCO) (THF): 2041 m,
(Ph). 13C NMR (C4D8O): δ 138.4, 137.1, 137.0, 136.3, 135.2, 130.2,
129.9, 129.7, 129.5, 129.2, 129.0. Anal. Calcd for C38H25O8Te2Se3-
CoMn2: C, 35.93; H. 1.98. Found: C, 36.73; H, 2.16.
Safety Note. Perchlorate salts of metal complexes with organic
ligands are potentially explosiVe. Only small amounts of material
should be prepared, and these should be handled with great caution.
Reaction of PhSeBr and [PPN][Mn(CO)5]. [PPN][Mn(CO)5]
(0.147 g, 0.2 mmol)8 was added to PhSeBr (47.2 mg, 0.2 mmol) in
THF (5 mL) around -20 °C. A vigorous reaction occurred immediately
and was monitored with FTIR. The IR spectrum, νCO (THF) 2116 w,
2027 s, 2000 m cm-1, having the same pattern as but differing slightly
in position from that of PhTeRe(CO)5 (IR (νCO) (THF): 2128 w, 2024
s, 1986 m cm-1),9 indicated the formation of PhSeMn(CO)5. The
reaction mixture was stirred for 4 h at ambient temperature; the IR
spectrum showed four new bands attributed to the well-known carbonyl
stretching modes of Mn2(µ-SePh)2(CO)8.9,10 IR (νCO) (THF): 2065 m,
1969 vs, 1950 m, 1908 m cm-1 1H NMR (CD3CN): δ 6.9-7.7 (m)
.
ppm. 13C NMR (CD3CN): δ 137.0, 134.5, 133.1, 130.2, 129.2, 128.4,
127.1, 124.9 ppm. Absorption spectrum (THF) [λmax, nm (ꢀ, M-1
cm-1)]: 438 (1660), 364 (2219), 290 (23 139). Anal. Calcd for
C52H40O4NP2Se2Mn: N, 1.38; C, 61.37; H, 3.96. Found: N, 1.54; C,
61.04; H, 4.05.
2012 vs, 1998 m, 1962 s cm-1
.
Reaction of [PPN][Mn(CO)4(SePh)2] and NOPF6. A solution
containing 0.102 g (0.1 mmol) of [PPN][Mn(CO)4(SePh)2] and 35 mg
(0.2 mmol) of NOPF6 in acetonitrile (10 mL) was stirred under nitrogen
overnight at room temperature. The green-orange solution was dried
under vacuum; THF-diethyl ether (2:1 ratio) was added to the residue,
and the mixture was filtered to remove the insoluble solid. The green-
orange solution was dried again under vacuum, and THF-hexane (1:
10 ratio) was added to precipitate the known pale yellow solid fac-
Preparation of [PPN][(CO)3Mn(µ-SePh)3Mn(CO)3]. cis-[PPN]-
[Mn(CO)4(SePh)2] (0.5 mmol, 0.509 g) in 20 mL of THF was heated
at 60 °C under nitrogen for 6 h. When the solution was cooled to
room temperature, the volume of the solution was reduced to 10 mL
under vacuum and diethyl ether (10 mL) was added. The red-brown
solution was filtered to remove [PPN][SePh], and recrystallization from
THF-diethyl ether (1:2 ratio) gave an orange-brown solid [PPN]-
[(CO)3Mn(µ-SePh)3Mn(CO)3]. The yield was 0.285 g (88.7%). IR
[Mn(CO)3(CH3CN)3][PF6].11 IR (νCO) (THF): 2060 m, 1970 vs cm-1
.
(νCO) (THF): 1981 s, 1902 vs cm-1 1H NMR (CD3CN): δ 7.0-7.9
.
1H NMR (CD3CN): δ 2.31 (s) ppm (CH3CN) (free CH3CN is noted at
(m) (Ph) ppm. Absorption spectrum (THF) [λmax, nm (ꢀ, M-1 cm-1)]:
409 (2768), 312 (7704), 273 (20 128). Anal. Calcd for C60H45O6NP2-
Se3Mn2: N, 1.09; C, 56.09; H, 3.53. Found: N, 1.43; C, 56.08; H,
3.81.
1.94 (s) ppm).
(9) Liaw, W.-F.; Horng, Y.-C.; Ou, D.-S.; Chuang, C.-Y.; Lee, C.-K.;
Lee, G.-H.; Peng, S.-M. J. Chin. Chem. Soc. (Taipei) 1995, 42, 59.
(10) Chaudhuri, M. K.; Hass, A.; Wensky, A. J. Organomet. Chem. 1976,
116, 323.
(8) Inkrott, K.; Goetze, G.; Shore, S. G. J. Organomet. Chem. 1978, 154,
337.

2532 Inorganic Chemistry, Vol. 35, No. 9, 1996
Liaw et al.
Table 1. Crystallographic Data for Complexes 1 and 2
Table 2. Crystallographic Data for Complexes 3 and 4
1
2
3
4
empirical formula
fw
cryst syst
space group
λ, Å (Mo KR)
a, Å
C60H56O6NP2MnSe2
1161.90
triclinic
P1h
0.7107
10.892(8)
10.992(7)
27.021(4)
101.93(4)
89.79(5)
116.94(5)
2807(3)
2
C23H39O14Mn2Se3Na
1017.13
trigonal
R3h
0.7107
empirical formula
fw
cryst syst
space group
λ, Å(Mo KR)
a, Å
C38H25O8CoMn2Se3Te2
1270.49
triclinic
P1h
C24H15O6MnSe3Fe
747.04
monoclinic
P21/n
0.7107
0.7107
13.533(3)
11.712(3)
12.197(3)
15.754(3)
83.558(18)
76.133(17)
72.686(18)
2083.8(7)
2
2.025
50.0
25
0.040
8.7066(16)
17.413(4)
17.541(4)
b, Å
c, Å
b, Å
c, Å
32.292(8)
R, deg
R, deg
â, deg
â, deg
99.718(18)
γ, deg
γ, deg
V, Å3
5122(2)
6
1.769
59.3
25
0.042
0.041
V, Å3
2621.2(10)
4
1.893
26.7
25
0.033
0.030
Z
F
Z
F
calcd, g cm-3
1.375
16.1
25
0.085
calcd, g cm-3
µ, cm-1
T, °C
Ra
µ, cm-1
T, °C
Ra
b
b
Rw
0.094
Rw
0.040
2
2
a R ) ∑|Fo - Fc|/∑Fo. b Rw ) [∑w(Fo - Fc)2/∑wFo ]1/2
.
a R ) ∑|Fo - Fc|/∑Fo. b Rw ) [∑w(Fo - Fc)2/∑wFo ]1/2
.
Table 3. Selected Bond Distances (Å) and Angles (deg) for 1 and 2
Reaction of cis-[Mn(CO)4(SePh)2]- and I2. A solution of I2 (51
mg, 0.2 mmol) in THF (5 mL) was added dropwise to cis-[PPN][Mn-
(CO)4(SePh)2] (0.204 g, 0.2 mmol) in THF solution under nitrogen at
ambient temperature. The solution was dried under vacuum, and hexane
was added to extract the green-yellow product (SePh)2 identified by
1H NMR and GC. The residue was identified as the well-known cis-
[Mn(CO)4(I)2]- product.12 IR (νCO) (THF): 2066 w, 1994 s, 1971 m,
(a) cis-[PPN][Mn(CO)4(SePh)2]
Se(1)-Mn
Se(2)-Mn
Se(1)-C(5)
Se(2)-C(11)
2.529(4)
2.524(4)
1.970(17)
1.952(19)
Mn-C(1)
Mn-C(2)
Mn-C(3)
Mn-C(4)
1.736(24)
1.776(21)
1.805(22)
1.799(22)
Se(1)-Mn-Se(2)
Mn-Se(1)-C(5)
Mn-Se(2)-C(11)
C(2)-Mn-C(4)
C(2)-Mn-C(3)
C(1)-Mn-C(2)
C(3)-Mn-C(4)
82.97(13)
104.1(5)
105.6(6)
94.1(11)
90.7(10)
96.5(12)
93.7(11)
Se(1)-Mn-C(1)
Se(1)-Mn-C(2)
Se(1)-Mn-C(3)
Se(1)-Mn-C(4)
C(1)-Mn-C(4)
C(1)-Mn-C(3)
86.7(8)
91.5(7)
177.7(7)
86.6(7)
167.5(12)
92.6(11)
.
1927 m cm-1 cis-[Mn(CO)4(I)2]- was also obtained by dropwise
addition of I2 to [PPN][Mn(CO)5] in THF.
Preparation of (CO)3Mn(µ-SePh)3Fe(CO)3. fac-[PPN][Fe(CO)3-
(SePh)3] (0.573 g, 0.5 mmol) in 5 mL of THF was slowly added to a
stirred THF solution of fac-[Mn(CO)3(CH3CN)3][PF6] (0.2035 g, 0.5
mmol)11 at ambient temperature. The reaction mixture was allowed
to stir for 3 h at room temperature. The solution was concentrated to
1 mL, and diethyl ether was added to extract the brown-red product
by filtering to remove [PPN][PF6]. The solution was then dried under
vacuum, and diethyl ether-hexane (1:2 ratio) was added to extract the
pure dark red-brown product. Upon removal of diethyl ether-hexane
in vacuum, dark red-brown solid (CO)3Mn(µ-SePh)3Fe(CO)3 (0.220
g, 59%) was obtained. Crystals suitable for X-ray diffraction were
grown from diethyl ether at -10 °C. IR (νCO) (THF): 2081 s, 2031
(b) [Na-18-crown-6-ether][(CO)3Mn(µ-SeMe)3Mn(CO)3]
Se-Mn(1)
Se-C(3)
2.508(2)
1.981(8)
Se-Mn(2)
2.494(2)
Mn(1)-Se-C(3)
Mn(2)-Se-C(3)
Mn(1)-Se-Mn(2)
Se-Mn(1)-Se
108.1(3)
106.9(3)
82.15(6)
81.23(6)
Se-Mn(2)-Se
81.79(6)
95.2(3)
91.9(4)
Se-Mn(1)-C(1)
Se-Mn(1)-C(1)
Se-Mn(1)-C(1)
172.7(2)
sh, 2017 vs, 1931 s cm-1 1H NMR (CD3CN): δ 7.27-8.02 (m) ppm.
.
Results and Discussion
13C NMR (CD3CN): δ 126.9, 130.0, 130.2, 132.2, 135.3, 203.2, 171.6
ppm. Anal. Calcd for C24H15O6Se3MnFe: C, 38.59; H, 2.02. Found:
C, 38.34; H, 2.40.
The chemistry reported herein is summarized in Scheme 1.
The reaction of diphenyl diselenide with [Mn(CO)5]- proceeds
cleanly in dry THF to form cis-[Mn(CO)4(SePh)2]- via an
oxidative decarbonylation addition at room temperature (Scheme
1a). This is in contrast to the reaction with [Re(CO)5]-, which
forms neutral PhSeRe(CO)5.14 The nature of the metal fragment
environment clearly plays a critical role in determining the
course of these reactions. In contrast to oxidative addition of
diphenyl diselenide to [Mn(CO)5]-, reaction of [Mn(CO)5]- with
PhSeBr in THF at 0 °C proceeded in surprising fashion to give
the monomeric species PhSeMn(CO)5 as the initial product
according to IR (νCO) spectra (Scheme 1c).9,15 The monomeric
PhSeMn(CO)5 was unstable with respect to CO loss and
dimerization when the reaction mixture was allowed to stir at
room temperature (Scheme 1d). The dimerization or transfor-
mation product (CO)4Mn(µ-SePh)2Mn(CO)4 was well-known
Crystallography. The crystal data are summarized in Tables 1 and
2. The crystal of 1 moderately sensitive to air chosen for diffraction
measurement was ca. 0.20 × 0.25 × 0.50 mm; the orange-red crystal
of 2 had dimensions 0.40 × 0.50 × 5.00 mm; the dark purple crystal
of 3 had dimensions 0.05 × 0.40 × 0.40 mm; the crystal of 4 that was
extremely sensitive to light and heat was 0.30 × 0.35 × 0.50 mm.
Each crystal was mounted on a glass fiber and quickly coated in epoxy
resin. The unit-cell parameters were obtained from 25 reflections with
2θ between 14.90 and 21.42° for product 1; the ranges were 15.20 ° <
2θ < 24.52° for product 2, 15.64° < 2θ < 24.66° for product 3, and
16.32° < 2θ < 24.24° for product 4. Diffraction measurements were
carried out on a Nonius CAD 4 diffractometer with graphite-
monochromated Mo KR radiation employing the θ/2θ scan mode. A
æ scan absorption correction was made. Structural determinations were
made using the NRCC-SDP-VAX package of programs.13 Selected
bond distances and angles are listed in Tables 3 and 4. Fractional
atomic coordinates and Beq values (Å2) of complexes 1-4 are listed in
Tables 5-8.
1
and identified by H NMR and IR.9,10
An atmosphere of CO failed to prevent oxidative addition of
PhSeSePh even when we exposed the mixture of [Mn(CO)5]-
and (PhSe)2 to 1 atm of CO in THF at room temperature. The
hexane-insoluble cis-[Mn(CO)4(SePh)2]- was recrystallized as
(11) Drew, D.; Darensbourg, D. J.; Darensbourg, M. Y. Inorg. Chem. 1975,
14, 1579.
(12) Abel, E. W.; Wilkinson, G. J. Chem. Soc. 1959, 1501.
(13) Gabe, E. J.; LePage, Y.; Chrarland, J. P.; Lee, F. L.; White, P. S. J.
Appl. Crystallogr. 1989, 22, 384.
(14) Liaw, W.-F.; Lee, W.-Z. Unpublished results.
(15) Osborne, A. G.; Stone, F. G. A. J. Chem. Soc. A 1966, 1143.

Complexes with Selenolate and Tellurolate Ligands
Inorganic Chemistry, Vol. 35, No. 9, 1996 2533
Table 4. Selected Bond Distances (Å) and Angles (deg) for 3 and 4
(a) (CO)4Mn(µ-TePh)2Co(CO)(µ-SePh)3Mn(CO)3
Table 6. Fractional Atomic Coordinates and Beq Values (Å2) for
[Na-18-crown-6-ether][(CO)3Mn(µ-SeMe)3Mn(CO)3]a
b
Te(1)-Co
Te(2)-Co
Se(1)-Co
Se(2)-Co
Se(3)-Co
Co-C(1)
Mn(2)-C(5)
Mn(2)-C(6)
Mn(2)-C(7)
Mn(2)-C(8)
2.581(2)
2.570(2)
2.476(2)
2.429(2)
2.444(2)
1.761(10)
1.860(11)
1.796(12)
1.844(11)
1.798(12)
Te(1)-Mn(2)
Te(2)-Mn(2)
Se(1)-Mn(1)
Se(2)-Mn(1)
Se(3)-Mn(1)
C(1)-O(1)
Mn(1)-C(2)
Mn(1)-C(3)
Mn(1)-C(4)
2.678(2)
2.630(2)
2.530(2)
2.503(2)
2.524(2)
1.136(12)
1.784(11)
1.762(12)
1.791(11)
x
y
z
Beq
Se
0.07104(7)
0
0
0.1254(6)
0.1267(7)
0.2398(6)
0.2037(5)
0.2066(5)
0.16049(7)
0
0
0.0642(7)
0.0655(7)
0.2380(7)
0.1040(5)
0.1065(6)
0.14826(3)
0.09704(6)
0.19882(6)
0.06596(22)
0.22908(22)
0.1492(3)
2.96(5)
2.56(7)
2.72(7)
3.1(5)
3.6(5)
4.1(5)
4.9(4)
5.8(4)
Mn(1)
Mn(2)
C(1)
C(2)
C(3)
O(1)
O(2)
0.04419(17)
0.25063(18)
b
8
a Esd’s refer to the last digit printed. Beq ) /3π2∑i∑jUijai*aj*aiaj.
Co-Te(1)-Mn(2)
Co-Te(2)-Mn(2)
Co-Se(1)-Mn(1)
Co-Se(2)-Mn(1)
Co-Se(3)-Mn(1)
Te(1)-Co-Te(2)
Te(1)-Co-Se(2)
Te(1)-Co-C(1)
Te(2)-Co-Se(2)
Te(2)-Co-C(1)
Se(1)-Co-Se(3)
Se(2)-Co-Se(3)
Se(3)-Co-C(1)
93.59(6) Co-Te(1)-C(9)
94.99(6) Co-Te(2)-C(15)
80.94(6) Co-Se(1)-C(21)
82.41(6) Co-Se(2)-C(27)
81.69(6) Co-Se(3)-C(33)
85.17(5) Te(1)-Co-Se((1)
88.77(6) Te(1)-Co-Se(3)
108.5(3)
105.9(3)
112.1(3)
116.6(3)
107.1(3)
96.55(6)
173.18(6)
174.80(6)
96.12(6)
83.56(6)
93.8(3)
Table 7. Fractional Atomic Coordinates and Beq Values (Å2) for
a
(CO)4Mn(µ-TePh)2Co(CO)(µ-SePh)3Mn(CO)3
b
x
y
z
Beq
Te(1)
Te(2)
Se(1)
Se(2)
Se(3)
Co
0.67830(7)
0.59129(7)
0.89220(9)
0.59982(10)
0.80433(10)
0.75082(13)
0.41032(6)
0.41734(7)
0.11505(9)
0.17203(9)
0.12237(9)
0.26925(12)
0.37842(5)
0.18078(5)
0.32517(7)
0.33014(7)
0.14578(7)
0.25322(9)
0.28284(10)
0.28205(12)
0.1942(7)
0.3871(8)
0.2519(7)
0.2416(7)
0.3378(8)
0.2094(9)
0.2341(8)
0.3620(8)
0.3885(7)
0.3512(7)
0.3555(8)
0.3966(9)
0.4355(9)
0.4327(8)
0.0525(7)
-0.0118(9)
-0.0953(9)
-0.1197(10)
-0.0606(10)
0.0264(8)
0.4498(7)
0.5100(7)
0.6000(7)
0.6315(8)
0.5719(8)
0.4823(7)
0.2731(7)
0.3270(8)
0.2964(10)
0.2086(10)
0.1523(9)
0.1855(8)
0.0886(7)
0.1151(8)
0.0670(8)
-0.0031(8)
-0.0293(8)
0.0174(7)
0.1531(5)
0.4534(5)
0.2337(5)
0.2172(6)
0.3684(7)
0.1624(7)
0.2069(5)
0.4126(6)
3.75(4)
4.70(4)
3.07(5)
3.60(5)
3.26(5)
3.26(7)
3.68(9)
4.23(10)
3.8(6)
4.8(7)
4.8(7)
4.4(6)
6.0 (8)
5.8(8)
5.0(7)
5.4(7)
3.8(6)
4.3(6)
5.2(7)
6.2(8)
6.0(8)
4.8(7)
4.9(6)
7.2(10)
10.8(14)
11.3(14)
12.9(15)
8.6(10)
4.1(6)
4.7(6)
4.9(7)
5.6(8)
6.0(8)
4.6(6)
3.9(6)
6.5(8)
8.3(10)
8.1(11)
7.7(10)
6.2(8)
4.0(6)
5.4(7)
6.6(8)
6.4(8)
6.7(9)
5.3(7)
6.0(5)
7.5(6)
6.2(5)
6.3(5)
9.0(7)
9.3(7)
6.2(5)
7.2(6)
95.0(3)
91.59(6) Te(2)-Co-Se(3)
90.9(3)
Te(2)-Co-Se(1)
Se(1)-Co-Se(2)
81.61(6) Se(1)-Co-C(1)
84.51(6) Se(2)-Co-C(1)
175.6(3)
80.99(6)
81.35(6)
Mn(1) 0.77181(15) -0.00343(14)
Mn(2) 0.56421(15)
91.7(3)
Se(1)-Mn(1)-Se(2)
0.58471(14)
0.3296(9)
Se(1)-Mn(1)-Se(3) 79.00(6) Se(2)-Mn(1)-Se(3)
Te(1)-Mn(2)-Te(2) 82.09(6)
C(1)
C(2)
C(3)
C(4)
C(5)
C(6)
C(7)
C(8)
C(9)
0.8672(9)
0.7344(10)
0.8987(10)
0.6773(10)
0.4165(10)
0.4918(11)
0.7159(10)
0.5435(10)
0.8311(9)
-0.0734(9)
-0.1233(10)
-0.0667(9)
0.5555(11)
0.6928(10)
0.6071(9)
0.6872(10)
0.4696(8)
0.4127(9)
0.4608(10)
0.5598(10)
0.6132(10)
0.5693(9)
0.4479(10)
0.3800(12)
0.3888(15)
0.4650(16)
0.5362(17)
0.5269(13)
0.1315(8)
(b) (CO)3Mn(µ-SePh)3Fe(CO)3
Fe-Se(1)
2.449(1)
2.444(1)
2.502(1)
1.953(7)
1.937(7)
Fe-Se(2)
2.461(1)
2.477(1)
2.492(1)
1.917(8)
Fe-Se(3)
Mn-Se(1)
Mn-Se(3)
Se(2)-C(13)
Mn-Se(2)
Se(1)-C(7)
Se(3)-C(19)
C(10) 0.9495(10)
C(11) 1.0420(10)
C(12) 1.0161(11)
C(13) 0.8975(11)
C(14) 0.8040(10)
C(15) 0.6839(10)
C(16) 0.6780(12)
C(17) 0.7382(16)
C(18) 0.7999(16)
C(19) 0.8042(17)
C(20) 0.7450(14)
C(21) 0.8585(9)
C(22) 0.7579(10)
C(23) 0.7456(10)
C(24) 0.8343(11)
C(25) 0.9361(12)
C(26) 0.9465(10)
C(27) 0.4677(9)
C(28) 0.3576(11)
C(29) 0.2589(11)
C(30) 0.2699(11)
C(31) 0.3792(12)
C(32) 0.4804(10)
C(33) 0.9763(10)
C(34) 1.0714(11)
C(35) 1.1925(11)
C(36) 1.2136(11)
C(37) 1.1215(12)
C(38) 0.9991(11)
Se(1)-Fe-Se(2)
Se(2)-Fe-Se(3)
Se(1)-Mn-Se(3)
Fe-Se(1)-Mn
Fe-Se(3)-Mn
C(1)-Fe-C(3)
C(4)-Mn-C(5)
C(5)-Mn-C(6)
80.59(4)
82.27(4)
81.92(4)
82.68(4)
82.48(5)
93.6(4)
Se(1)-Fe-Se(3)
Se(1)-Mn-Se(2)
Se(2)-Mn-Se(3)
Fe-Se(2)-Mn
C(1)-Fe-C(2)
C(2)-Fe-C(3)
C(4)-Mn-C(6)
83.48(4)
79.24(4)
80.51(4)
81.92(4)
96.4(4)
94.5(3)
91.7(4)
90.9(4)
87.3(4)
Table 5. Fractional Atomic Coordinates and Beq Values (Å2) for
cis-[PPN][Mn(CO)4(SePh)2]a
0.1129(9)
b
x
y
z
Beq
0.1165(10)
0.1382(10)
0.1572(10)
0.1532(9)
Mn
0.7914(3)
0.7945(3)
0.6776(3)
0.6247(24)
0.8777(25)
0.784(3)
0.9490(24)
0.8217(22)
0.9497(21)
0.960(3)
0.4549(3)
0.6571(3)
0.5362(3)
0.355(3)
0.4148(23)
0.3113(23)
0.582(3)
0.6159(20)
0.7038(24)
0.674(3)
0.24437(12)
0.31015(9)
0.18655(10)
0.2587(9)
0.2893(8)
0.1958(8)
0.2264(9)
0.3756(6)
0.4062(8)
0.4544(8)
0.4699(8)
0.4368(8)
0.3922(7)
0.1193(7)
0.0967(8)
0.0506(8)
0.0234(8)
0.0439(9)
0.0922(8)
0.2707(7)
0.3171(5)
0.1680(6)
0.2157(7)
4.75(19)
5.92(15)
7.10(18)
7.6(17)
6.2(16)
6.7(17)
6.9(16)
4.6(13)
6.6(15)
9.1(21)
7.8(20)
6.1(15)
5.8(15)
5.7(15)
7.3(17)
8.4(21)
8.2(19)
9.7(19)
7.3(15)
10.5(14)
7.1(11)
10.0(15)
9.9(14)
Se(1)
Se(2)
C(1)
C(2)
C(3)
C(4)
C(5)
C(6)
C(7)
C(8)
C(9)
C(10)
C(11)
C(12)
C(13)
C(14)
C(15)
C(16)
O(1)
O(2)
O(3)
O(4)
0.1789(8)
0.1851(12)
0.1845(13)
0.1776(12)
0.1704(13)
0.1706(11)
0.1015(9)
0.0218(10)
0.0127(11)
0.0819(12)
0.1625(11)
0.1728(10)
0.3669(7)
-0.1219(7)
-0.2061(7)
-0.1112(7)
0.5349(9)
0.7620(8)
0.6258(7)
0.854(3)
0.562(3)
0.7403(23)
0.7176(22)
0.7346(22)
0.819(3)
0.849(3)
0.802(3)
0.4839(23)
0.5083(23)
0.4937(24)
0.596(3)
0.561(3)
0.430(3)
0.322(3)
0.355(3)
0.2936(20)
0.3856(16)
0.2195(17)
0.6673(20)
O(1)
O(2)
O(3)
O(4)
O(5)
O(6)
O(7)
O(8)
0.9420(7)
0.7109(9)
0.9790(7)
0.6183(7)
0.3279(7)
0.4477(9)
0.8074(7)
0.5300(7)
0.718(3)
0.6775(24)
0.5069(19)
0.9306(16)
0.7865(22)
1.0504(18)
0.7533(7)
b
8
b
8
a Esd’s refer to the last digit printed. Beq ) /3π2∑i∑jUijai*aj*aiaj.
a Esd’s refer to the last digit printed. Beq ) /3π2∑i∑jUijai*aj*aiaj.
1
atmosphere in THF, permitting full characterization by IR, H
moderately air-sensitive crystals from THF-hexane under CO
atmosphere at -10 °C and could be stored infinitely under CO
NMR, elemental analysis, and X-ray diffraction (Figure 1). The
complex cis-[Mn(CO)4(SePh)2]- is intensely colored, presum-

2534 Inorganic Chemistry, Vol. 35, No. 9, 1996
Liaw et al.
Table 8. Fractional Atomic Coordinates and Beq Values (Å2) for
(CO)3Mn(µ-SePh)3Fe(CO)3
cm-1 (THF)) almost completely disappeared, followed by
formation of a new four-band pattern (2031 w, 1960 s, 1938
a
1
m, 1894 m cm-1 (THF)) in the IR νCO region. The single H
b
x
y
z
Beq
NMR resonance (δ 1.53 (s) ppm (CD3CN)) observed for -CH3
ligands suggested equivalent methaneselenolate environments,
and its upfield chemical shift (vs (MeSe)2) provided the evidence
for formation of manganese(I) methaneselenolate. 1H NMR and
IR measurements of νCO showed formation of orange solid cis-
[Mn(CO)4(SeMe)2]-. The general reaction shown in Scheme
1a with diphenyl diselenide appears to be valid for dimethyl
diselenide; however, reaction of [Mn(CO)5]- and (MeSe)2 is
slower. Upon being stirred for extended periods under CO
atmosphere in THF at ambient temperature, a solution of cis-
[Mn(CO)4(SeMe)2]- converted into a red-brown solution. The
1H NMR and IR (νCO) spectra and X-ray diffraction revealed
the complex to be a methaneselenolate-triply-bridged dimer of
composition [(CO)3Mn(µ-SeMe)3Mn(CO)3]- (Figure 2). These
results show the relative order of thermal stability of anionic
manganese(I)-selenolate complexes is cis-[Mn(CO)4(SePh)2]-
> cis-[Mn(CO)4(SeMe)2]-, implying that a more electron-
donating ligand destabilizes the monomeric manganese(I)-
selenolate-carbonyl complexes.
Fe
Mn
Se(1)
Se(2)
Se(3)
C(1)
C(2)
C(3)
C(4)
C(5)
C(6)
C(7)
C(8)
C(9)
C(10)
C(11)
C(12)
C(13)
C(14)
C(15)
C(16)
C(17)
C(18)
C(19)
C(20)
C(21)
C(22)
C(23)
C(24)
O(1)
O(2)
O(3)
O(4)
O(5)
O(6)
0.65880(12)
0.93161(12)
0.64780(9)
0.89089(9)
0.84296(9)
0.5055(10)
0.7071(9)
0.5273(9)
1.1313(10)
0.9785(9)
0.9332(9)
0.5382(8)
0.4380(10)
0.3537(12)
0.3700(13)
0.4695(12)
0.5568(10)
0.8107(8)
0.7645(12)
0.7012(12)
0.6884(13)
0.7382(12)
0.7986(11)
0.9782(9)
1.0986(10)
1.1900(11)
1.1611(14)
1.0417(14)
0.9481(11)
0.4098(7)
0.7389(7)
0.4405(7)
1.2624(7)
1.0156(7)
0.9352(7)
0.53633(6)
0.40769(6)
0.40240(4)
0.53377(4)
0.48597(4)
0.5257(5)
0.6341(5)
0.5619(4)
0.4240(5)
0.3509(4)
0.3209(5)
0.3378(4)
0.2858(5)
0.2376(5)
0.2439(6)
0.2957(5)
0.3419(5)
0.5308(5)
0.5990(5)
0.6010(6)
0.5355(7)
0.4689(6)
0.4655(5)
0.5694(4)
0.5982(5)
0.6582(5)
0.6869(6)
0.6597(6)
0.5996(6)
0.5206(4)
0.6959(3)
0.5789(3)
0.4332(4)
0.3104(4)
0.2631(3)
0.20995(6)
0.24975(7)
0.25121(5)
0.31180(5)
0.13160(5)
0.1279(5)
0.1907(5)
0.2744(5)
0.2480(5)
0.3340(5)
0.1952(5)
0.1685(5)
0.1915(6)
0.1362(7)
0.0607(7)
0.0394(5)
0.0926(5)
0.4070(4)
0.4353(6)
0.5011(6)
0.5434(5)
0.5170(6)
0.4495(6)
0.1118(5)
0.1668(5)
0.1481(7)
0.0759(8)
0.0200(6)
0.0396(5)
0.0753(4)
0.1790(4)
0.3131(3)
0.2468(4)
0.3865(4)
0.1636(4)
3.21(5)
3.28(6)
3.28(4)
3.52(4)
3.48(4)
4.6(5)
4.2(4)
3.7(4)
4.9(5)
4.3(4)
4.0(4)
3.6(4)
5.7(5)
7.3(6)
7.2(6)
6.4(6)
5.0(5)
3.7(4)
5.7(5)
6.7(6)
6.9(6)
7.0(6)
5.9(5)
3.7(4)
4.8(5)
6.7(6)
7.4(7)
7.7(7)
6.4(5)
7.0(4)
6.7(4)
5.5(3)
7.3(4)
6.6(4)
6.6(4)
As a part of comprehensive exploration of metal chalcogeno-
lates, we examined the reactivity of manganese-selenolate
species cis-[Mn(CO)4(SeR)2]- (R ) Ph, Me) and attempted to
synthesize heterometallic mixed-chalcogenolate complexes by
adopting cis-[Mn(CO)4(SeR)2]- as a precursor. cis-[Mn(CO)4-
(SePh)2]- and cis-[Mn(CO)4(TePh)2]- were reacted in stoichio-
metric proportions with Co(ClO4)2‚6H2O and (PhSe)2 (1:1:1:
0.5 molar ratio) in THF under a nitrogen atmosphere, and the
reaction mixture finally led to the isolation of the dark purple
heterometallic mixed chalcogenolate (CO)4Mn(µ-TePh)2Co-
(CO)(µ-SePh)3Mn(CO)3 (Scheme 1e). Here the cis-[Mn(CO)4-
(SePh)2]- and cis-[Mn(CO)4(TePh)2]- are able to act as
“chelating metallo ligands” for a Co2+ species.17 The proposed
mechanism is shown in Scheme 2; oxidation of Co2+ of the
coordination compound (CO)4Mn(µ-TePh)2CoII(µ-SePh)2Mn-
(CO)4 by diphenyl diselenide led to the presumed intermediate
(CO)4Mn(µ-TePh)2Co(SePh)(µ-SePh)2Mn(CO)4, and subsequent
rearrangement of the terminal benzeneselenolate ligand to bridge
two metals and shift of a labile carbonyl from Mn(I) to Co(III)
yielded neutral (CO)4Mn(µ-TePh)2Co(CO)(µ-SePh)3Mn(CO)3.17c
The result clearly indicated that the reaction pathway in Scheme
2a is adopted instead of the pathway in Scheme 2b. The
formation of the complex (CO)4Mn(µ-TePh)2Co(CO)(µ-
SePh)3Mn(CO)3 provides insight into the preferred stereochem-
istry of Co(III)-selenolate-tellurolate complexes, and the
mechanism is relevant to the oxidative Bennett approach using
a Esd’s refer to the last digit printed. Beq ) /3π2∑i∑jUijai*aj*aiaj.
b
8
ably due to the chalcogen to Mn(I) charge transfer excitation.
In the UV-visible region cis-[Mn(CO)4(SePh)2]- does not
exhibit ligand-field transitions. At room temperature, cis-[Mn-
(CO)4(SePh)2]- in THF solution lost CO to form bezeneselen-
olate-triply-bridged [(CO)3Mn(µ-SePh)3Mn(CO)3]-. This trans-
formation occurred slowly in ambient temperature over 48 h,
during which period no intermediate was detected spectrally
(Scheme 1b).
To evaluate the influence of Se-Se bond strength of
diorganyl diselenides on oxidative addition to [Mn(CO)5]- 16
and the reactivity of cis-[Mn(CO)4(SeR)2]- (R ) Ph, Me) which
may be tailored by pendant ligand selection, the attempted
synthesis of cis-[Mn(CO)4(SeMe)2]- in a manner analogous to
that for cis-[Mn(CO)4(SePh)2]- by reaction of 1 equiv of
[Mn(CO)5]- and 1 equiv of (MeSe)2 was investigated in THF
around -20 °C. The IR spectrum (ν(CO) (THF): 2114 w, 2027
s, 1998 m cm-1, C4ν pattern) in the carbonyl stretching region
in the course of the reaction between [Mn(CO)5]- and (MeSe)2
clearly indicated the presence of an intermediate, presumably
A.
(RS)2 and Co2+ 18
The light- and air-sensitive (CO)4Mn(µ-
.
TePh)2Co(CO)(µ-SePh)3Mn(CO)3, which is stable in nonpolar
hexane-ether, was easily crystallized from ether-hexane at -10
°C and partially decomposed into insoluble solid in THF-CH3-
1
CN overnight at room temperature. The H and 13C NMR
spectra of (CO)4Mn(µ-TePh)2Co(CO)(µ-SePh)3Mn(CO)3 shows
the expected signals (1H NMR (C4D8O) δ 6.95-8.24 (m) ppm;
(16) Treichel, P. M.; Nakagaki, P. C. Organometallics 1986, 5, 711.
(17) (a) White, G. S.; Stephan, D. W. Inorg. Chem. 1985, 24, 1499. (b)
Wark, T. A.; Stephan, D. W. Inorg. Chem. 1990, 29, 1731. (c)
Waldbach, T. A.; van Rooyen, P. H.; Lotz, S. Angew. Chem., Int. Ed.
Engl. 1993, 32, 710.
(18) (a) Lane, R. H.; Bennett, L. E. J. Am. Chem. Soc. 1970, 92, 1089. (b)
Asher, L. E.; Deutsch, E. Inorg. Chem. 1975, 14, 2799. (c) Weschler,
C. J.; Deutsch, E. Inorg. Chem. 1973, 12, 2682. (d) Lane, R. H.;
Sedor, F. A.; Gilroy, M. J.; Eisenhardt, P. F.; Bennett, L. E. Inorg.
Chem. 1977, 16, 93. (e) Dickman, M. H.; Doedens, R. J.; Deutsch,
E. Inorg. Chem. 1980, 19, 945. (f) Koch, S.; Tang, S. C.; Holm, R.
H.; Frankel, R. B. J. Am. Chem. Soc. 1975, 97, 914.
When the temperature of the reaction mixture was raised to
25 °C, the carbonyl stretching bands (2114 w, 2027 s, 1998 m

Complexes with Selenolate and Tellurolate Ligands
Inorganic Chemistry, Vol. 35, No. 9, 1996 2535
Scheme 1
Scheme 2
SeMe)3Mn(CO)3. No decomposition was observed in THF at
room temperature for 3 days. However, when attempting to
isolate the analogue (CO)4Mn(µ-SePh)2Co(CO)(µ-SePh)3Mn-
(CO)3 by drying under vacuum and extracting with diethyl ether,
we isolated only an insoluble dark solid. It seems that the
strongly basic chelating metallo ligand cis-[Mn(CO)4(SeMe)2]-
can better stabilize the trinuclear Mn(I)-Co(III)-Mn(I)-
chalcogenolate complex than the weakly basic chelating metallo
ligand cis-[Mn(CO)4(SePh)2]-. In brief, the electronic and
solvent effects play important roles in stabilizing the Mn(I)-
Co(III)-Mn(I)-chalcogenolate complexes.
The chemical oxidation of cis-[Mn(CO)4(SePh)2]- with
oxidants was investigated. It was hoped that one-electron
oxidation would lead to formation of an Se-Se bond that would
likely undergo an aggregation process resulting in higher
nuclearity species. Unfortunately, with the addition of 2 equiv
of NOPF6 to 1 equiv of cis-[Mn(CO)4(SePh)2]- in CH3CN at
room temperature, the identifiable products are the well-known
fac-[Mn(CO)3(CH3CN)3]+ along with (PhSe)2, identified by 1H
NMR and gas chromatography (Scheme 1f).11 The oxidation
process was also investigated using I2 as the oxidant. Dropwise
addition of I2 solution to a solution of cis-[Mn(CO)4(SePh)2]-
in THF at room temperature produced the isostructural product
cis-[Mn(CO)4(I)2]-, on the basis of the infrared carbonyl
stretching spectra, and (PhSe)2, characterized by 1H NMR and
GC.12 Presumably, the reaction undergoes reductive elimination
followed by oxidative addition (Scheme 1h).
13C NMR (C4D8O) δ 129.0-138.4 (m) ppm) for the phenyl
ligands involved and display characteristics of diamagnetic d6
Co(III) and d6 Mn(I) species.
To evaluate the influence of the more electron-donating
groups on the reactivity with Co2+, we surveyed the reactivity
of dimethyl diselenide toward Co(ClO4)2‚6H2O in the presence
of cis-[Mn(CO)4(SeMe)2]- (eq 1). An immediate reaction
2cis-[Mn(CO)4(SeMe)2]- + Co(ClO4)2‚6H2O + 1/2(MeSe)2 f
(CO)4Mn(µ-SeMe)2Co(CO)(µ-SeMe)3Mn(CO)3 (1)
The anionic [(CO)3Mn(µ-SeR)3Mn(CO)3]- (R ) Ph, Me)
feature octahedral coordination about each of the two Mn(I)
ions with three terminal carbonyls in the facial positions and
bear a closer structural resemblance to the recently reported [Fe-
(CO)3(SePh)3Na‚3THF] in which the d6 Fe(II) [Fe(CO)3]+
fragment is isolobal with the d6 Mn(I) [Mn(CO)3]+ fragment
ensued under the same reaction conditions. The IR carbonyl
stretching (2068 w, 2027 sh, 1998 vs, 1981 sh, 1961 w, 1917
1
m cm-1 (THF)) and H NMR (C4D8O) (δ 2.20 (s), 2.00 (s),
1.93 (s), 1.86 (s), 1.57 (s) ppm) and 13C NMR (C4D8O) (δ 5.88
(s), 4.99 (s), 3.41 (s), 3.36 (s), 2.20 (s) ppm) spectra confirm
the formation of the neutral (CO)4Mn(µ-SeMe)2Co(CO)(µ-

2536 Inorganic Chemistry, Vol. 35, No. 9, 1996
Liaw et al.
Figure 1. ORTEP drawing and labeling scheme of the cis-[Mn(CO)4-
(SePh)2]- anion with thermal ellipsoids drawn at the 50% probability
level.
Figure 2. ORTEP drawing and labeling scheme of the [(CO)3Mn(µ-
SeMe)3Mn(CO)3]- anion with thermal ellipsoids drawn at the 50%
probability level.
of [(CO)3Mn(µ-SeR)3Mn(CO)3]-.1b Attempts to prepare a
heterometallic manganese-iron-selenolate complex in a straight-
forward manner by the simple salt elimination reaction between
fac-[PPN][Fe(CO)3(SePh)3] and fac-[Mn(CO)3(CH3CN)3][PF6]
led to the neutral (CO)3Mn(µ-SePh)3Fe(CO)3 in THF (Scheme
1g). The IR carbonyl stretching (ν(CO) (THF): 2081 m, 2031
are 0.146 Å longer than those of Mn-Se in 1, and the bond
angle 82.97(13)° for Se-Mn-Se in 1 is slightly larger than
the 82.79(4)° Te-Mn-Te bond angle in cis-[Mn(CO)4-
(TePh)2]-, which might be accredited to the longer Mn-Te
bonds. The presumed delocalized pairs of electrons along Se-
Mn-Se in 1 reflects the tetrahedral array around the selenium
atoms with Mn-Se(1)-C(5) 104.1(5)° and Mn-Se(2)-C(11)
105.6(6)°.
1
sh, 2017 s, 1931 s cm-1) and H NMR spectra (δ (CD3CN)
7.27-8.02 (m) ppm) are consistent with the presence of the
low-spin octahedrally coordinated d6 Fe(II) and d6 Mn(I) ions
with facial carbonyls. The light-sensitive, thermally unstable
(CO)3Mn(µ-SePh)3Fe(CO)3 was formed as dark brown-red
crystals in good yield after recrystallization from diethyl ether.
X-ray diffraction confirmed the formation of (CO)3Mn(µ-
SePh)3Fe(CO)3, which is isostructural with [(CO)3Mn(µ-
SeMe)3Mn(CO)3]- (Figure 4). In light of these results, this
synthetic procedure proved useful in the preparation of hetero-
metallic chalcogenolates.
The structure of [(CO)3Mn(µ-SeMe)3Mn(CO)3]- is shown in
Figure 2. Table 3 gives a listing of significant bond lengths
and angles for complex 2. The anion 2 contains two Mn atoms,
and each is coordinated by three terminal CO ligands and three
bridging MeSe ligands. To a first approximation, the MnSe3-
(CO)3 framework may be described as face-sharing octahedra.
The methyl groups of three bridging µ2-methaneselenolates in
2 form a regular propeller-like arrangement around the Se3 plane
defined by the three seleniums. [(CO)3Mn(µ-SeMe)3Mn(CO)3]-
contains dinuclear units in which Mn(I) centers are unsym-
metrically bridged by three µ2-methaneselenolates. The Mn(1)-
Se bonds of average length 2.508(3) Å are 0.012 Å longer than
Mn(2)-Se bonds (average distance 2.496(3) Å). The µ2-
bridging Mn-Se bonds of average length 2.502(3) Å in 2 are
0.112 Å shorter than bridging Mn-Se bonds (average distance
2.614(2) Å) in [Mn{N(SiMe3)2}(µ-SeC6H2-i-Pr3-2,4,6)‚THF]2.21
An ORTEP projection of the neutral trinuclear (CO)4Mn(µ-
TePh)2Co(CO)(µ-SePh)3Mn(CO)3 is shown in Figure 3. The
selected bond distances and angles are listed in Table 4.
Complex 3 has a linear chain of two Mn atoms and one Co
atom; the central cobalt ion is bridged by two benzenetelluro-
lates, three benzeneselenolates, and a terminal CO, thus
completing the octahedral coordination sphere of the Co(III)
ion. While one of the two outer Mn ions is coordinated by
three terminal carbonyls and three bridging PhSe ligands,
another Mn atom is coordinated by two bridging PhTe ligands
and four terminal carbonyls. Overall, the geometry around each
of three metals may be described as a distorted octahedron. The
Co(III)-Se distances observed in 3 (average 2.450(2) Å) are
much longer than that observed in [(en)2Co(SeCH2CH2NH2)]-
[(NO3)2] (2.378(1) Å).22 The Co(III)-Te bond distances of
2.576(2) Å (average) are slightly shorter than those in the
recently reported (CO)4Mn(µ-TePh)2Co(CO)(µ-TePh)3Mn(CO)3
(average distance 2.589(5) Å);2 however, they are comparable
with the Co(I)-Te bond distance of 2.543(1) Å in Co(TeSi-
(SiMe3)3)(PMe3)3.23 The longer Co(III)-CO bond distance
Structure. Due to the facile CO lability of cis-[Mn(CO)4-
(SePh)2]-, an atmosphere of CO was present to force the
formation of cis-[PPN][Mn(CO)4(SePh)2] crystals over that of
the CO loss product [(CO)3Mn(µ-SePh)3Mn(CO)3]- at -10 °C.
The crystal structure of cis-[PPN][Mn(CO)4(SePh)2]‚2THF
consists of well-separated cations and anions and two THF
solvent molecules; there are no exceptional cation-anion
interactions. The PPN+ cations show the expected geometry.
The manganese ion in complex 1 is surrounded in a distorted
octahedral fashion by two terminal benzeneselenolate groups
and four carbonyls with a bond angle of 82.97(13)° for Se(1)-
Mn-Se(2) (Figure 1). Inspection of the angle between cis-
benzeneselenolate-coordination sites highlights the extent to
which the molecule is distorted. This acute angle appears to
result from intramolecular interaction of the two selenium sp3
lone pairs. Surprisingly, two carbonyl ligands (C(4)-O(4) and
C(1)-O(1)) tilt toward the benzeneselenolates (Se(2)-Mn-
C(4) 83.6(8)°, Se(2)-Mn-C(1) 85.1(9)°). These Mn-Se
distances (2.529(4) and 2.524(4) Å) in 1 are much shorter than
the terminal Mn-Se bonds in the anion [Mn(SePh)4]2- (average
2.567 Å)19 but longer than the terminal Mn-Se bonds in Mn-
(SeC6H3-2,6-Mes2)2‚2CH2Cl2 (2.498(1) Å).3c The Se(1)‚‚‚Se(2)
contact distance (3.347(4) Å) in 1 shows no formal Se-Se bond;
however, this contact distance is inside of the sum of the van
der Waals radii (4.0 Å).20 A comparison of the structure of
complex 1 with its previously published Te analogue cis-[Mn-
(CO)4(TePh)2]- reveals a very close correspondence of structural
details.2 The Mn-Te bond lengths in cis-[Mn(CO)4(TePh)2]-
(19) Tremel, W.; Krebs, B.; Greiwe, K.; Simon, W.; Stephan, H. O.; Henkel,
G. Z. Naturforsch., B 1992, 47B, 1580.
(20) (a) Pauling, L. The Nature of the Chemical Bond, 2nd ed.; Cornell
University Press: Ithaca, NY, 1960; p 260. (b) Wolmersha¨user, G.;
Heckmann, G. Angew. Chem., Int. Ed. Engl. 1992, 31, 779.
(21) Bochmann, M.; Powell, A. K.; Song, X. Inorg. Chem. 1994, 33, 400.
(22) Stein, C. A.; Ellis, P. E.; Elder, R. C., Jr.; Deutsch, E. Inorg. Chem.
1976, 15, 1618.

Complexes with Selenolate and Tellurolate Ligands
Inorganic Chemistry, Vol. 35, No. 9, 1996 2537
Figure 3. ORTEP drawing and labeling scheme of neutral (CO)4Mn-
(µ-TePh)2Co(CO)(µ-SePh)3Mn(CO)3 with thermal ellipsoids drawn at
the 50% probability level.
Figure 4. ORTEP drawing and labeling scheme of neutral (CO)3Mn-
(µ-SePh)3Fe(CO)3 with thermal ellipsoids drawn at the 50% probability
level.
Se angles (average 80.56(4)°). It is possible that the larger Se-
Fe(II)-Se angle is due to the proximity of the bridging-
benzeneselenolate groups to the Fe(II) center. The C-Fe(II)-C
bond angles (average 94.8(4)°) are also larger than the C-Mn-
(I)-C bond angles (average 90.0(4)°) observed in 4.
(1.761(10) Å) observed in 3 compared with the Co(III)-CO
bond distance 1.75(3) Å in (CO)4Mn(µ-TePh)2Co(CO)(µ-
TePh)3Mn(CO)3 is, presumably, ascribed to the weaker σ-donat-
ing ability of benzeneselenolate trans to the Co-CO bond (bond
angle Se(2)-Co-C(1) 175.6(3)°). It is not surprising that the
bite angle Te(1)-Co-Te(2) of the “chelate (CO)4Mn(µ-TePh)2”
is 85.17(5)° in 3, which is slightly larger than the Se-Co-Se
average angle of 83.23(6)°. The Te(1)-Mn(2)-Te(2) bond
angle (82.09(6)°) in 3 is comparable with the Te-Mn-Te bond
angle, 82.79(4)°, in starting material cis-[Mn(CO)4(TePh)2]-.
The selenium atoms of the triply-bridging benzeneselenolates
adopt a severely distorted tetrahedral arrangement of three
bonding pairs and one lone pair of electrons because of the sharp
Co-Se-Mn bridge angles (average Mn-Se-Co bond angle
81.68(6)°).
Conclusion. The syntheses of new Mn(I)-selenolate com-
plexes, cis-[Mn(CO)4(SeR)2]- (R ) Ph, Me) and [(CO)3Mn-
(µ-SeR)3Mn(CO)3]-, have been achieved by oxidative addition
of (RSe)2 to cis-[Mn(CO)5]- and thermal transformation of cis-
[Mn(CO)4(SeR)2]-, respectively. Our efforts also have been
directed to clarify the course of reactions (oxidative addition
vs nucleophilic displacement) in reactions of cis-[Mn(CO)5]-
with (RSe)2 and PhSeBr individually. Concerning reactivities
of cis-[Mn(CO)4(SeR)2]- and fac-[Fe(CO)3(SePh)3]-, we showed
that cis-[Mn(CO)4(SeR)2]- and fac-[Fe(CO)3(SePh)3]- act as
“chelating metallo ligands” in the syntheses of the heterometallic
chalcogenolate compounds (CO)4Mn(µ-TePh)2Co(CO)(µ-
SePh)3Mn(CO)3 and (CO)3Mn(µ-SePh)3Fe(CO)3. We also
made a comparison between “chelating metallo ligands” cis-
[Mn(CO)4(SeMe)2]- and cis-[Mn(CO)4(SePh)2]- in light of
chelating ability; the electronic and solvent effects play crucial
roles in stabilizing the mixed-metal Mn(I)-Co(III)-Mn(I)-
chalcogenolate complexes.
The molecular structure of the neutral (CO)3Mn(µ-SePh)3Fe-
(CO)3 with the atomic numbering scheme is shown in Figure
4, with selected bond lengths and angles given in Table 4. In a
sense, neutral complex 4 is isostructural with the anion
[(CO)3Mn(µ-SeMe)3Mn(CO)3]-. Compound 4 contains discrete
dinuclear units in which the d6 Fe(II) and d6 Mn(I) ions are
unsymmetrically bridged by three benzeneselenolates. The
average Fe-SePh bond length of 2.451(1) Å in 4 is comparable
with the reported terminal Fe-SePh bond length of 2.459(2) Å
in fac-[Fe(CO)3(SePh)3]-,1b 2.460(12) Å in tetrahedral
Acknowledgment. We thank the National Science Council
of the Republic of China (Taiwan) for support of this work.
[Fe(SePh)4]2- 24
, and 2.421(1) Å in Fe(Se-2,6-i-Pr2C6H3)2(PMe2-
Ph)2.25 Oddly, the bridging Mn-Se distances (average 2.490(1)
Å) are marginally (ca. 0.037 Å) shorter than the terminal Mn-
Se bond distances in 1. The Se-Fe(II)-Se angles average
82.11(4)°, which is significantly larger than the Se-Mn(1)-
Supporting Information Available: Tables of crystal data and
experimental conditions for the X-ray studies, atomic coordinates and
B
eq values, bond lengths and angles, and anisotropic temperature factors
for cis-[Mn(CO)4(SePh)2]-, [(CO)3Mn(µ-SeMe)3Mn(CO)3]-, (CO)4Mn-
(µ-TePh)2Co(CO)(µ-SePh)3Mn(CO)3, and (CO)3Mn(µ-SePh)3Fe(CO)3
(25 pages). Ordering information is given on any current masthead
page.
(23) Gindelberger, D. E.; Arnold, J. Inorg. Chem. 1993, 32, 5813.
(24) McConnachie, J. M.; Ibers, J. A. Inorg. Chem. 1991, 30, 1770.
(25) Forde, C. E.; Morris, R. H.; Ramachandran, R. Inorg. Chem. 1994,
33, 5647.
IC951487T