Synthesis of cyclic diamino-substituted metal carbene complexes

Article abstract of DOI:10.1021/om950735q

A series of heterocyclic metal carbene complexes were prepared by the deoxygenation reaction of M(CO)₆ (M = Cr, Mo, W) with RNH(CH₂)_nN=PPh₃ (R = H, Et, Ph; n = 2, 3, 4) to form the corresponding isocyanide complex, which subsequently underwent intramolecular cyclization to give (CO)₅M=CN(R)(CH₂)_nNH in good yields. None of the carbene complex reacted further with amine-phosphinimine RNH(CH₂)_nN=PPh₃ to give the bis(carbene) complex. Deprotonation of the N-H of the carbene complex followed by the reaction of alkyl iodides provided the N-alkylated product. In the case of N-allyl-substituted complexes (CO)₅M=CNR(CH₂)₂N(CH₂CH=CH ₂) (M = Cr, Mo, W), the carbon-carbon double bond underwent intramolecular ligand displacement of carbonyl ligand to yield the corresponding Π-coordinated complex. Unlike the group VI metal carbonyl complexes, treatment of ReBr(CO)₅ with 2 molar equiv of Ph₃P=N(CH₂)₂NH₂ provided a bis(carbene) complex fac-(CO)₃BrRe(=CNHCH₂CH₂NH)₂. All complexes are characterized by both spectral and elemental analyses. Complexes (CO)₅Mo=CNHCH₂CH₂CH₂NH (18) andfac-(CO)₃BrRe-(=CNHCH₂CH₂NH)₂ (42) were further characterized by X-ray single-crystal analysis.

Full text of DOI:10.1021/om950735q

Organometallics 1996, 15, 1055-1061
1055
Syn th esis of Cyclic Dia m in o-Su bstitu ted Meta l Ca r ben e
Com p lexes
Chung-Yuan Liu, Der-Yi Chen, Gene-Hsiang Lee, Shie-Ming Peng, and
Shiuh-Tzung Liu*
Department of Chemistry, National Taiwan University, Taipei, Taiwan 106, Republic of China
Received September 15, 1995X
A series of heterocyclic metal carbene complexes were prepared by the deoxygenation
reaction of M(CO)6 (M ) Cr, Mo, W) with RNH(CH2)nNdPPh3 (R ) H, Et, Ph; n ) 2, 3, 4)
to form the corresponding isocyanide complex, which subsequently underwent intramolecular
cyclization to give (CO)5MdCN(R)(CH2)nNH in good yields. None of the carbene complex
reacted further with amine-phosphinimine RNH(CH2)nNdPPh3 to give the bis(carbene)
complex. Deprotonation of the N-H of the carbene complex followed by the reaction of alkyl
iodides provided the N-alkylated product. In the case of N-allyl-substituted complexes
(CO)5MdCNR(CH2)2N(CH2CHdCH2) (M ) Cr, Mo, W), the carbon-carbon double bond
underwent intramolecular ligand displacement of carbonyl ligand to yield the corresponding
π-coordinated complex. Unlike the group VI metal carbonyl complexes, treatment of
ReBr(CO)5 with 2 molar equiv of Ph3PdN(CH2)2NH2 provided a bis(carbene) complex fac-
(CO)3BrRe(dCNHCH2CH2NH)2. All complexes are characterized by both spectral and
elemental analyses. Complexes (CO)5ModCNHCH2CH2CH2NH (18) and fac-(CO)3BrRe-
(dCNHCH2CH2NH)2 (42) were further characterized by X-ray single-crystal analysis.
In tr od u ction
well explored. It was reported by Fehlhammer and co-
workers that (CO)5CrCNCCl3 reacted with dithiols or
diamines to yield the heterocyclic electron-rich carbene
complex 1.6 It is also known that the stable amino-
substituted metal carbene species 1 (Z ) NR) can be
obtained by oxidative addition of tetraamino-substituted
olefins or related species to metal carbonyl complexes.12
One of the synthetic strategies for producing metal
carbene complexes is nucleophilic addition to coordi-
nated isocyanide ligands to form the corresponding
carbene complex. While relevant examples applying
this approach to prepare Pd(II), Pt(II), Zn(II), Au(I),
Au(III), Co(III), and Rh(II) carbene complexes have been
studied, 1-11 the reactivity of group VI metal carbonyl-
isocyanide complexes toward nucleophiles has not been
X Abstract published in Advance ACS Abstracts, J anuary 15, 1996.
(1) (a) Michelin, R. A.; Zanotto, L.; Braga, D.; Sabation, P.; Angelici,
R. J . Inorg. Chem. 1988, 27, 85. (b) Michelin, R. A.; Zanotto, L.; Braga,
D.; Sabation, P.; Angelici, R. J . Inorg. Chem. 1988, 27, 93. (c) J ohnson,
L. K.; Angelici, R. J . Inorg. Chem. 1987, 26, 973.
(2) (a) Grundy, K. R.; Roper, W. R. J . Organomet. Chem. 1975, 91,
C61. (b) Fehlhammer, W. P.; Bartel, K.; Petri, W. J . Organomet. Chem.
1975, 87, C34. (c) Fehlhammer, W. P.; Volkl, A.; Plaia, U.; Beck, G.
Chem. Ber. 1987, 120, 2031. (d) Fehlhammer, W. P.; Achatz, D.; Plaia,
U.; Volkl, A. Z. Naturforsch. 1987, 42B, 720. (e) Fehlhammer, W. P.;
Zinner, G.; Bakola-Christianopulou, M. J . Organomet. Chem. 1987,
331, 193.
Recently, we reported that phosphinimine-phosphine
Ph3PdN(CH2)3PPh2 (2) reacted with group VI metal
carbonyls to yield two different type of products (Scheme
1) while the phosphine site of complex 3 remained
uncoordinated.13 Here, we describe the replacement of
the phosphine site of the phosphinimine 2 by a nitrogen
donor and their activity in the formation of cyclic
carbene complexes.
(3) Fuchita, Y.; Hidaka, K.; Morinaga, S. Hiraki, K. Bull. Chem. Soc.
J pn. 1981, 54, 800.
(4) (a) Bertani, R.; Mozzon, M.; Michelin, R. A.; Benetollo, F. Inorg.
Chem. 1988, 27, 2809. (b) Bertani, R.; Mozzon, M.; Michelin, R. A.;
Benetollo, F.; Bombieri, G.; Castilho, T. J .; Pombeiro, A. J . L. Inorg.
Chim. Acta 1991, 189, 175. (c) Belluco, U.; Michelin, R. A.; Ros, R.;
Bertani, R.; Facchin, G.; Mozzon, M.; Zanotto, L. Inorg. Chim. Acta
1992, 200, 883.
(5) (a) Plaia, U.; Stolzenberg, H.; Fehlhammer, W. P. J . Am. Chem.
Soc. 1985, 107, 2171. (b) Fehlhammer, W. P.; Bartel, K.; Plaia, U.;
Volkl, A.; Liu, A. T. Chem. Ber. 1985, 118, 2235. (c) Dussel, R.; Pilette,
D.; Dixneuf, P. H.; Fehlhammer, W. P. Organometallics 1991, 10, 3287.
(d) Fehlhammer, W. P.; Ahn, S.; Beck, G. J . Organomet. Chem. 1991,
411, 181.
(6) (a) Fehlhammer, W. P.; Beck, G. J . Organomet. Chem. 1989, 369,
105. (b) Bartel, K.; Fehlhammer, W. P. Angew. Chem., Int. Ed. Engl.
1974, 13, 599.
(7) Bartel, K.; Fehlhammer, W. P. Angew. Chem., Int. Ed. Engl.
1974, 13, 599.
(9) (a) Facchin, G.; Campostrini, R.; Michelin, R. A. J . Organomet.
Chem. 1985, 294, C21. (b) Michelin, R. A.; Facchin, G.; Braga, D.;
Sabatino, P. Organometallics 1986, 5, 2265. (c) Michelin, R. A.; Mozzon,
M.; Facchin, G. J . Chem. Soc., Dalton Trans. 1988, 1803. (d) Facchin,
G.; Mozzon, M.; Michelin, R. A.; Ribeiro, M. T. A.; Pombeiro, A. J . L.
J . Chem. Soc., Dalton Trans. 1992, 2827.
(10) Beck, G.; Fehlhammer, W. P. Angew. Chem., Int. Ed. Engl.
1988, 27, 1344.
(11) (a) Cotton, F. A.; Troup, J . M.; Webb, T. R.; Williamson, D. H.;
Wilkinson, G. J . Am. Chem. Soc. 1974, 96, 3824. (b) Churchill, M. R.;
O’Brien, T. A. J . Chem. Soc. A 1969, 1110. (c) Lappert, M. F.; Pye, P.
L. J . Less-Common Met. 1977, 54, 191.
(12) (a) Hitchcock, P. B.; Lappert, M. F.; Pye, P. L. J . Chem. Soc.,
Dalton Trans. 1977, 2160. (b) Lappert, M. F.; Pye, P. L.; McLaughlin,
G. M. J . Chem. Soc., Dalton Trans. 1977, 1272. (c) Lappert, M. F.;
Pye, P. L. J . Chem. Soc., Dalton Trans. 1977, 1283.
(8) Fehlhammer, W. P.; Finck, W. J . Organomet. Chem. 1991, 414,
261.
(13) Liu, C.-Y.; Chen, D.-Y.; Cheng, M.-C.; Peng, S.-M.; Liu, S.-T.
Organometallics 1995, 14, 1983.
0276-7333/96/2315-1055$12.00/0 © 1996 American Chemical Society

1056 Organometallics, Vol. 15, No. 3, 1996
Liu et al.
Sch em e 1
Sch em e 4
the isocyanide species, which is subsequently attacked
by the amine moiety in an intramolecular fashion.13,6
Both five- and six-membered rings of the carbene
complexes can be obtained under mild conditions, but
the reaction of 11 with W(CO)6 under similar conditions
only provided the isocyanide complex (CO)5WCN(CH2)4-
NH2 (25) exclusively, which was isolated and character-
ized. This outcome is quite similar to the species
(CO)5CrCN(CH2)4NH2 obtained from the reaction of
(CO)5CrCNCCl3 with NH2(CH2)4NH2 by Fehlhammer
and co-workers,6a which did not undergo intramolecular
cyclization to form the carbene species. However,
complex 25 was slowly converted into the corresponding
carbene complex 20 by addition of diethylamine in the
reaction mixture.
Sch em e 2
Sch em e 3
When the nitrogen center became a secondary amine
moiety, the nucleophilic attack at isocyanide to form
carbene complexes still proceeded (Scheme 3). The
present route to form diaminocarbene complexes is more
versatile than the oxidative addition of amino-substi-
tuted olefins to metal centers.12 In order to test the
nucleophilicity of phosphinimine, a bis(phosphinimine)
26 was made to react with an equal molar amount of
W(CO)6. The reaction only provided a dinuclear iso-
cyanide complex 27 (Scheme 4). It appears that the
nitrogen center of phosphinimine did not undergo nu-
cleophilic attack at isocyanide or carbonyl ligand in-
tramolecularly, instead it reacted with another carbonyl
ligand intermolecularly to form 27.
N-Alk yla tion a n d Liga n d Su bstitu tion . The N-H
moieties of carbene complexes are readily converted into
the N-alkylated species by treatment of the complexes
with excess of sodium hydride followed by alkylated
agents. This procedure is quite similar to that reported
by Angelici and co-worker.1c Thus a series of sym-
metrical and unsymmetrical diamino-substituted car-
bene complexes 28-35 were prepared by this method.
In terms of alkylating reagents, it was found that the
alkyl iodides were better than the corresponding bro-
mides. The N-allyl-substituted metal carbene com-
plexes readily underwent intramolecular ligand substi-
tution to form π-bond coordinated species 36-39. The
Resu lts a n d Discu ssion
Syn th esis. A series of amino-phosphinimines (9-
13) were prepared by the reaction of the corresponding
azido compounds (4-8) with triphenylphosphine under
extremely dry conditions which gave high yields (Scheme
2). All amino-phosphinimines were isolated as viscous
liquids except 9, which was isolated as a white solid.
Formulation of these phosphinimines was confirmed by
spectral analysis. The 31P NMR shifts for phosphin-
imines were in the range of 10-15 ppm (relative to 85%
H3PO4) typical for such functionality. Both infrared and
1H NMR spectra show the NH moiety for the com-
pounds.
Molar equivalents of M(CO)6 (M ) Cr, Mo, W) and
phosphinimine 9 or 10 were reacted in dry tetrahydro-
furan solvent with stirring at 25 °C (Scheme 3). Upon
purification, all carbene complexes could be obtained as
crystalline solids in good yields. Formation of the
carbene complex had been expected via the deoxygen-
ation of the carbonyl ligand by phosphinimine to form
tungsten complex 32, as typical in refluxing THF
solutions, provided the substituted product 39. Due to
geometrical constraints, the second allyl group of 35
does not coordinate to the metal center. Because of the

Diamino-Substituted Metal Carbenes
Organometallics, Vol. 15, No. 3, 1996 1057
same constraints on the proparagyl group, the π-bond
coordinated species was not formed in 31.
Bis(ca r ben e) Com p lexes. Attempts to prepare the
bis(carbene) species were unsuccessful. No reaction was
observed when equal molar amounts of 18 and 9 were
heated in refluxing THF; neither were the chromium
and tungsten analogues formed. As discussed earlier,
the formation of the carbene species requires the forma-
tion of isocyanide by the reaction of the phosphinimine
with carbonyl ligand followed by the attack of an amine
function. Apparently, the carbonyl ligands in 18 do not
further react with phosphinimine to form isocyanide 40.
F igu r e 1. ORTEP plot of molybdenum carbene complex
18.
Ta ble 1. Selected Bon d Dista n ces (Å) a n d Bon d
An gles (d eg) for 18
Mo-C(1)
Mo-C(2)
Mo-C(3)
Mo-C(4)
Mo-C(5)
Mo-C(6)
C(6)-N(1)
C(6)-N(2)
2.03(1)
2.03(1)
1.98(1)
2.02(1)
2.06(1)
2.26(1)
1.31(1)
1.31(1)
C(1)-O(1)
C(2)-O(2)
C(3)-O(3)
C(4)-O(4)
C(5)-O(5)
N(1)-C(7)
N(2)-C(9)
1.14(1)
1.14(1)
1.15(1)
1.14(1)
1.13(1)
1.46(1)
1.46(1)
This is consistent with our previous studies, which show
that metal carbonlys M(CO)6 (M ) Cr, Mo, W) do not
react with 2 molar equiv of phosphinimine 2 to yield
bis(isocyanide) complexes. Analysis of the infrared
absorptions of carbonyl ligands revealed that, upon
carbene formation in metal complexes (carbene)M(CO)5,
the carbonyl stretching frequency shifted to smaller
wavenumber. Such a shift is expected due to the
weaker π-acceptor ability of carbene ligands, resulting
in an increase in the strength of M-C back-bonding
which reduces the electrophilic character of such carbon
centers.
In our previous studies, the treatment of BrRe(CO)5
with 2 equiv molar of phosphine-phosphinimine 2
yielded a bis(isocyanide) complex.13 Accordingly, the
reaction of phosphinimine 9 with ReBr(CO)5 provided
the carbene complex 41, which subsequently reacted
Mo-C(6)-N(1)
Mo-C(6)-N(2)
Mo-C(1)-O(1)
Mo-C(2)-O(2)
123.2(4)
122.8(4)
175.8(6)
176.6(6)
Mo-C(3)-O(3)
Mo-C(4)-O(4)
Mo-C(5)-O(5)
178.2(6)
178.8(6)
177.5(6)
distances and angles are reported in Table 1. As
expected from the spectral analysis of 18, the metal is
coordinated by the five carbonyl ligands and by the
carbene ligand in an octahedral environment. All bond
distances and bond angles lie within normal range. The
shorter distance of Mo-C(3) [1.98(1) Å] is due to the
trans influence of the carbene donor.
Examination of the dihedral angles along the chelate
ring of 18 revealed two angles approaching 0° [C(7)-
N(1)-C(6)-N(2) 0.0°; N(1)-C(6)-N(2)-C(9) 1.5°], typical
of a half-chair-like six-member ring, indicating that the
two nitrogen centers were in a planar geometry. This
is consistent with the distances of carbon-nitrogen [1.31
(1) Å] being typical for CdN double bond. The distance
of Mo-C(6) [2.262(6) Å] was significantly longer than
that of the reported metal carbene species (CO)5Mod
C(OR)SiPh3 [2.15(2) Å]14 indicating that the metal-
carbon bond had more single-bond characteristics. [The
distance of Mo-C in Cp2Mo(CO)CH3 is 2.24 Å.] Dihe-
dral angles N(2)-C(6)-Mo-C(4) and N(1)-C(6)-Mo-
C(1) were 53.9(4) and 54.8(4)°, respectively. Thus the
carbene moiety defined by plane of N(2)-C(6)-N(1) was
staggered with the Mo(CO)5 unit which is similar to
that of the reported metal carbene species (CO)5Mod
C(OR)SiPh3.14a,15
with another 1 equiv of 9 to give bis(carbene) complex
42. This outcome confirms that the phosphinimine only
reacts with highly electrophilic carbonyl ligands. In-
deed, carbonyl stretching frequencies of 41 appeared at
2105, 2003, and 1916 cm-1, which indicates a weak
Re-C back-bonding interaction in 41 as compared to
those in complexes of 14-24. Thus the carbonyl ligand
of 41 can be attacked by phosphinimine 9 to form a bis-
(carbene) complex.
Formulations of both rhenium complexes 41 and 42
were established by spectral and elemental analyses.
Infrared and 13C NMR spectra clearly showed the metal
carbonyl moieties and carbene carbon, respectively. The
facial arrangement of 42 was proved by its carbonyl
stretching pattern in the infrared spectrum and was
further confirmed by an X-ray single-crystal structure.
Cr ysta llogr a p h y. Carbene complex 18 was obtained
in a single-crystal form, and its structure was deter-
mined by the X-ray diffraction method. Figure 1 shows
a perspective view of the complex whose selected bond
Slow evaporation of a dichloromethane/hexane solu-
tion of 42 yielded clear colorless crystals suitable for
X-ray analysis. An ORTEP plot of 42 is illustrated in
Figure 2, and selected bond distances and angles are
listed in Table 2. The rhenium center displayed an
octahedral geometry with one face occupied by the three
carbonyl ligands. Bond lengths of Re-C(4)[2.14(2) Å]
(14) (a) Fischer, E. O.; Hollfelder, H.; Friedrich, P.; Kreissl, R. K.;
Huttner, G. Chem. Ber. 1977, 110, 2467. (b) Cardin, D. J .; Cetinkaya,
B.; Lappert, M. F. Chem. Rev. 1972, 72, 545.
(15) Ma´rquez, A.; Sanz, J . F. J . Am. Chem. Soc. 1992, 114, 2903.

1058 Organometallics, Vol. 15, No. 3, 1996
Liu et al.
under reduced pressure and trapped by liquid nitrogen to give
the title compound as a colorless liquid (1.2 g, 82%): IR (neat)
1
ν(Ν3) 2101 cm-1; H NMR δ 3.40 (t, J ) 5.8 Hz, 2 H), 2.76 (t,
J ) 5.8 Hz, 2 H), 2.64 (q, J ) 7.1 Hz, 2 H), 1.46 (br, 1 H), 1.08
(t, J ) 7.1 Hz, 3 H); 13C NMR δ 51.5, 48.2, 43.7, 15.2; HRMS
calcd for C4H10N4 m/e 114.0905, found m/e 114.0899.
N-(2-Azid oet h yl)p h en yla m in e (8). Preparation of this
compound is similar to that of compound 6 except the starting
material is Br(CH2)2NHPh‚HBr.16c A colorless liquid (82%)
forms: IR (neat) ν(N3) 2101 cm-1; 1H NMR δ 7.25-7.15 (m, 2
H), 6.82-6.63 (m, 3 H), 3.9 (br, 1 H), 3.52 (t, J ) 5.5 Hz, 2 H),
3.38 (m, 2 H); 13C NMR δ 147.1, 129.3, 117.9, 112.9, 50.4, 42.9.
HRMS calcd for C8H10N4 m/e 162.0905, found m/e 162.0901.
Gen er a l P r oced u r e for P r ep a r a tion of Am in o-P h os-
p h in im in es. To a solution of azido-amine in benzene was
added a solution of triphenylphosphine in benzene at 25 °C.
The resulted mixture was stirred for 6 h. After removal of
solvents, the desired product was obtained quantitatively
(moisture sensitive). The preparation of 9 is described below
as typical.
F igu r e 2. ORTEP plot of rhenium bis(carbene) complex
42.
P h 3P dN(CH2)2NH2 (9). To a solution of azido compound
4 (2.0 g, 23.2 mmol) in dry benzene (50 mL) was added a
solution of triphenylphosphine (6.1 g, 23.2 mmol) in benzene
(50 mL). The resulting mixture was stirred at 25 °C for 6 h.
After concentration of the reaction mixture, the residue was
washed with hexane (2 mL × 2). The desired product was
Ta ble 2. Selected Bon d Dista n ces (Å) a n d Bon d
An gles (d eg) for 42
Re-C(1)
Re-C(2)
Re-C(3)
Re-C(4)
Re-C(7)
Re-Br
1.88(2)
1.95(2)
1.91(2)
2.14(2)
2.17(2)
2.669(2)
1.14(2)
C(2)-O(2)
C(3)-O(3)
C(4)-N(1)
C(5)-N(2)
C(7)-N(3)
C(7)-N(4)
1.13(2)
1.17(2)
1.36(2)
1.31(2)
1.32(2)
1.32(2)
1
obtained as a white solid (7.30 g, 98%): mp 103-104 °C; H
3
NMR δ 7.75-7.20 (m, 15 H), 3.13 (dt, J P-H ) 16.5 Hz, J )
3
6.1 Hz, 2 H), 2.75 (dt, J P-H ) 1.1 Hz, J ) 6.1 Hz, 2 H), 1.85
C(1)-O(1)
(br, 2 H); 13C NMR δ (aliphatic) 48.5 (d, J P-C ) 5 Hz), 46.4 (d,
J P-C ) 19 Hz); 31P NMR δ 13.4; HRMS calcd for m/e C20H21N2P
320.1442, found m/e 320.1439.
Re-C(4)-N(1)
Re-C(4)-N(2)
Re-C(1)-O(1)
Re-C(2)-O(2)
127(1)
129(1)
179(2)
178(2)
Re-C(3)-O(3)
Re-C(7)-N(3)
Re-C(7)-N(4)
177(2)
128(1)
125(1)
P h 3P dN(CH2)3NH2 (10): Viscous liquid; 1H NMR δ 7.65-
3
7.24 (m, 15 H), 3.12 (dt, J P-H ) 17.5 Hz, J ) 6.7 Hz, 2 H),
2.71 (t, J ) 6.4 H, 2 H), 1.65 (m, 2 H), 1.00 (br, 2 H); 13C NMR
δ (aliphatic) 42.9(d, J P-C ) 6.5 Hz), 40.6, 39.0 (d, J P-C ) 17
Hz); 31P NMR δ 11.7; HRMS calcd for C21H23N2P m/e 334.1599,
found m/e 334.1578.
and Re-C(7) [2.17(2) Å] are typical for metal to carbene
centers, and the small difference between them is
believed to be due to the crystal packing since the
spectral data for the two carbon centers are indistin-
guishable. The distance of Re-C(1) trans to bromide
is slightly less than those trans to carbene ligands as
expected, because of the trans influences.
P h 3P dN(CH2)4NH2 (11): Viscous liquid; 1H NMR δ 7.66-
3
7.24 (m, 15 H), 3.06 (dt, J P-H ) 18 Hz, J ) 6.9 Hz, 2 H), 2.56
(t, J ) 6.9 Hz, 2 H), 1.50 (m, 2 H), 1.40 (m, 2 H), 0.96 (br, 2 H,
-NH); 13C NMR δ (aliphatic) 45.3 (d, J P-C ) 4.8 Hz), 42.2,
32.8 (d, J P-C ) 17.3 Hz), 31.7; 31P NMR δ 11.6; HRMS calcd
for m/e C22H25N2P 348.1755, found m/e 348.1749.
Exp er im en ta l Section
P h 3P dN(CH2)2NH(CH2CH3) (12): Viscous liquid; 1H NMR
3
δ 7.70-7.25 (m, 15 H), 3.22 (dt, J P-H ) 15.4, J ) 6.0 Hz, 2
Gen er a l In for m a tion . Nuclear magnetic resonance spec-
tra were recorded in CDCl3 on either a Bruker AC-E 200 or a
AM-300 spectrometer. For 31P NMR spectra, the chemical
shifts are given in parts per million (δ) relative to 85%
H3PO4. Infrared spectra were measured on a Biorad FT-30
instrument. Infrared spectra were obtained on Biorad FT-IR
instruments in CH2Cl2 solution, unless otherwise stated.
All of the reaction, manipulation, and purification steps
involving phosphines were performed under a dry nitrogen
atmosphere. Tetrahydrofuran was distilled under nitrogen
from sodium benzophenone ketyl. Benzene was distilled from
sodium under nitrogen. Dichloromethane was dried by CaH2
and then distilled under nitrogen. Other chemicals and
solvents were used from commercial sources without further
purification. Compounds 4-6 were prepared by the method
previously reported.16a
H), 2.75 (dt, 3J P-H ) 1.1, J ) 6.0 Hz, 2 H), 2.58 (q, J ) 7.1 Hz,
2 H), 1.70 (br, 1 H), 1.04 (t, J ) 7.1 Hz, 3 H); 13C NMR δ
(aliphatic) 53.9 (d, J P-C ) 20 Hz), 44.7 (d, J P-C ) 5.1 Hz), 43.9,
15.4; 31P NMR δ 12.6; HRMS calcd for C22H25N2P m/e 348.1755,
found m/e 348.1749.
P h 3P dN(CH2)2NHP h (13): Viscous liquid; 1H NMR δ
7.70-7.32 (m, 15 H), 7.13 (m, 2 H), 6.61 (m, 3 H), 4.5 (br, 1
H), 3.38 (dt, 3J P-H ) 16.7, 5.8 Hz, 2 H), 3.23 (m, 2 H); 13C NMR
δ (aliphatic) 47.5 (d, J P-C ) 17.5 Hz), 42.9 (d, J P-C ) 4.7 Hz);
31P NMR δ 14.4; HRMS calcd for C26H25N2P m/e 396.1755,
found m/e 396.1750.
Gen er a l P r oced u r e for P r ep a r a tion of Ca r ben e Com -
p lexes. A mixture of M(CO)6 [M ) Cr, Mo, W] and an equal
molar amount of amino-phosphinimine in THF solution was
stirred at 25 °C for 24 h. After concentration of the reaction
mixture, the residue was chromatographed on silica gel with
dichloromethane as the eluent. The eluate was concentrated,
and the residue was recrystallized from a solution of chloro-
form and pentane to give the desired complex in crystalline
solids. The preparation of 14 is described below as typical.
N-(2-Azid oeth yl)eth yla m in e (7). A solution of BrCH2-
CH2NHEt‚HBr16b (3.0 g, 12.9 mmol) and sodium azide (2.5 g,
38.5 mmol) in water (50 mL) was heated to reflux for 12 h.
The reaction mixture was neutralized with aqueous NaOH
solution and extracted with ether (100 mL × 2). After
concentration of the organic extracts, the residue was distilled
(CO)5Cr dCNHCH2CH2NH (14). A mixture of Cr(CO)6 (0.6
g, 2.73 mmol) and amine-phosphinimine 9 (0.88 g, 2.73 mmol)
in dry tetrahydrofuran was stirred at 25 °C for 10 h. After
removal of solvents, the residue was chromatographed on silica
gel (10 g) with dichloromethane as the eluent. A light yellow
band was collected and concentrated. The residue was re-
(16) (a) Carboni, B.; Benalil, A.; Vaultier, M. J . Org. Chem. 1993,
58, 3736. (b) Sarignac, P.; Dreux, M.; Ple, G. J . Organomet. Chem. 1973,
60, 103. (c) Pearlman, W. M. J . Am. Chem. Soc. 1948, 70, 871.
(17) Chamizo, J . A.; Hitchcock, P. B.; J asim, H. A.; Lappert, M. F.
J . Organomet. Chem. 1993, 451, 89.

Diamino-Substituted Metal Carbenes
Organometallics, Vol. 15, No. 3, 1996 1059
crystallized from a solution of chloroform and pentane to give
14 as a light yellow crystalline solid (0.54 g, 76%): mp 106-
107 °C [lit.6a mp 105 °C]; IR (νCO) 2058, 1924 cm-1; 1H NMR δ
6.03 (br, 2 H), 3.62 (s, 4 H); 13C NMR δ 221.8 (CrdC), 221.2,
217.9, 44.9. Anal. Calcd for C8H6N2O5Cr: C, 36.66; H, 2.31;
N, 10.69. Found: C, 36.54; H, 2.19; N, 10.53.
NMR δ 7.48-7.29 (m, 5 H), 6.15 (br, 1 H), 3.94 (m, 2 H), 3.79
(m, 2 H); 13C NMR δ 207.4 (WdC), 201.6, 197.9, 142.5, 129.6,
128.5, 128.1, 53.6, 45.7. Anal. Calcd for C14H10N2O5W: C,
35.77; H, 2.14; N, 5.96. Found: C, 34.11; H, 2.33; N, 6.25.
(CO)5WCN(CH2)4NH2 (25). A mixture of W(CO)6 (1.28 g,
3.64 mmol) and 11 (1.27 g, 3.64 mmol) in THF (50 mL) was
stirred at 25 °C for 48 h. The reaction mixture was concen-
trated, and the residue was chromatographed on silica gel with
acetone as the eluent. A yellow band was collected and
concentrated to give 25 as a yellow liquid (57%): IR (νNC) 2177
(CO)5ModCNHCH2CH2NH (15). A light yellow solid
1
formed (70%): mp 109-110 °C; IR (νCO) 2064, 1928 cm-1; H
NMR δ 6.02 (br, 2 H), 3.59 (s, 4 H); 13C NMR δ 213.5 (ModC),
211.9, 206.6, 44.6. Anal. Calcd for C8H6N2O5CMo: C, 31.39;
H, 1.98; N, 9.15. Found: C, 31.20; H, 2.01; N, 9.11.
1
cm-1, (νCO) 2068, 1945 cm-1; H NMR δ 3.67 (t, J ) 6.5 Hz, 2
H), 2.77 (t, J ) 6.8 Hz, 2 H), 1.82 (m, 2 H), 1.61 (m, 2 H), 1.50
(br, 2 H); 13C NMR δ 196.3, 194.3, 142.1 (CN-), 44.1, 41.0,
30.1, 26.6. Anal. Calcd for C10H10N2O5W: C, 28.46; H, 2.39;
N, 6.64. Found: C, 28.30; H, 2.59; N, 6.47.
(CO)5WdCNHCH2CH2NH (16). A light yellow solid formed
1
(87%): mp 129-130 °C; IR (νCO) 2064, 1921 cm-1; H NMR δ
5.97 (br, 2 H), 3.65 (s, 4 H); 13C NMR δ 204.0 (WdC), 201.8,
198.0, 45.1. Anal. Calcd for C8H6N2O5CW: C, 24.39; H, 1.53;
N, 7.11. Found: C, 24.31; H, 1.42; N, 7.09.
P h 3P dN(CH2)4NdP P h 3 (26). The preparation of 26 is
similar to the method described for 9 except N3(CH2)4N318 was
1
used. A white solid formed (99%): mp 112-113 °C (dec); H
NMR δ 7.64-7.26 (m, 30 H), 3.05 (m, 4 H), 1.58 (m, 4 H); 13
NMR δ (aliphatic) 45.70 (d, J P-C ) 5.3 Hz), 33.63 (d, J P-C
16.7 Hz); 31P NMR δ 10.64.
C
)
(CO)5Cr dCNH (CH2)3NH (17). A colorless solid formed
(66%): mp 142-143 °C [lit.6a mp 145 °C]; IR (νCO) 2055, 1921
cm-1; 1H NMR δ 6.03 (br, 2 H), 3.24 (dt, J ) 2.4, 5.9 Hz, 4 H),
1.94 (quint, J ) 5.9 Hz, 2 H); 13C NMR δ 221.7, 218.1, 214.8
(CrdC), 40.7, 19.7. Anal. Calcd for C9H8N2O5Cr: C, 39.14;
H, 2.92; N, 10.14. Found: C, 38.92; H, 2.82, N, 10.07.
(CO)5WCN(CH2)4NCW(CO)5 (27). A mixture of 26 (4.1 g,
6.9 mmol) and W(CO)6 (2.37 g, 6.7 mmol) in THF was stirred
at 25 °C for 48 h. After the concentration of the reaction
mixture, the residue was chromatographed on silica gel with
dichloromethane as the eluent. A yellow band was collected
and concentrated to give 27 as a yellow solid (43%): mp 112-
(CO)5ModCNH(CH2)3NH (18). A light yellow solid formed
1
(64%): mp 139-141 °C; IR (νCO) 2063, 1924 cm-1; H NMR δ
5.96 (br, 2 H), 3.22 (dt, J ) 2.5, 5.9 Hz, 4 H), 1.95 (quint, J )
5.9 Hz, 2 H); 13C NMR δ 212.1, 208.9 (ModC), 206.9, 40.2,
19.7. Anal. Calcd for C9H8N2O5Mo: C, 33.77; H, 2.52; N, 8.75.
Found: C, 33.78; H, 2.49; N, 8.51.
113 °C (dec); IR (νCN) 2171 cm-1, (νCO) 2066, 1948 cm-1 1H
;
NMR δ 3.78 (m, 4 H), 1.94 (m, 4 H); 13C NMR δ 195.9, 194.1,
144.6 (-NC), 43.4, 26.3. Anal. Calcd for C16H8N2O10W2: C,
25.42; H, 1.07; N, 3.71. Found: C 25.34; H, 1.09; N, 3.57.
Gen er a l p r oced u r es for N-Alk yla tion . To a solution of
diamino-substituted carbene complex in THF was added an
excess of sodium hydride with stirring overnight. The alky-
lating agent was then added to the reaction mixture and kept
stirring for another 8 h. Water was added at ice-cooled
temperature to quench the reaction. The organic layer was
separated, dried, and concentrated. The residue was chro-
matographed on silica gel with dichloromethane as the eluent.
A light yellow band was collected and concentrated to give the
desired alkylated product. The preparation of 28 is described
below as typical.
(CO)5WdCNH(CH2)3NH (19). A light yellow solid formed
1
(84%): mp 164-165 °C; IR (νCO) 2062, 1917 cm-1; H NMR δ
5.98 (br, 2 H), 3.23 (dt, J ) 2.4, 5.9 Hz, 4 H), 1.98 (quint, J )
5.9 Hz, 2 H); 13C NMR δ 202.0, 199.2 (WdC), 198.9, 40.5, 19.4.
Anal. Calcd for C9H8N2O5W: C, 26.49; H, 1.98; N, 6.87.
Found: C, 26.38; H, 1.92; N, 6.78.
(CO)5WdCNH(CH 2)4NH (20). Complex 25 (0.80 g, 1.90
mmol) in diethylamine (20 mL) was stirred for 48 h. After
concentration of the reaction mixture, the residue was chro-
matographed on silica gel with dichloromethane as the eluent.
A yellow band was collected and concentrated to give 20 as a
(CO)5Cr dCN(CH2CH3)CH2CH2N(CH2CH3) (28). A mix-
ture of 14 (700.0 mg, 2.67 mmol) and sodium hydride (0.3 g,
12.5 mmol) in THF was stirred for 24 h. Ethyl iodide (0.98 g,
6.3 mmol) was then added, and the reaction mixture was
stirred for another 8 h. Water (5 mL) was added to quench
the sodium hydride at ice-cooled temperature. The organic
layer was separated, dried, and concentrated. The residue was
chromatographed on silica gel with dichloromethane as the
eluent. A light yellow band was collected and concentrated
to give the desired alkylated product 28 as a light yellow
solid (0.64 g, 75%): mp 99-100 °C [ lit.12a mp 100-102 °C];
IR(νCO) 2054, 1929 cm-1; 1H NMR δ 3.82 (q, J ) 7.1 Hz, 4 H),
3.51 (s, 4 H), 1.24 (t, J ) 7.1 Hz, 6 H); 13C NMR δ 222.1, 219.2
(CrdC), 217.9, 47.7, 46.0, 13.6. Anal. Calcd for C12H14N2O5-
Cr: C, 45.29; H, 4.43; N, 8.80. Found: C, 45.15; H, 4.32; N,
8.75.
yellow solid (51%): mp 117-118 °C; IR (νCO) 2064, 1918 cm-1
;
C
1H NMR δ 6.07 (br, 2 H, NH), 3.42 (m, 4 H), 1.94 (m, 4 H); 13
NMR δ 202.0, 199.0, 194.2 (WdC), 46.4, 26.7. Anal. Calcd
for C10H10N2O5W: C, 28.46; H, 2.39; N, 6.64. Found: C, 28.53;
H, 2.27; N, 6.55.
(CO)5Cr dCN(CH2CH3)CH2CH2NH (21). A yellow crystal-
line solid formed (55%): mp 75-76 °C; IR (νCO) 2056, 1923
cm-1; 1H NMR δ 5.68 (br, 1 H), 3.73 (q, J ) 7.2 Hz, 2 H), 3.57
(m, 4 H), 1.26 (t, J ) 7.2 Hz, 3 H); 13C NMR δ 221.8, 219.2
(CrdC), 218.0, 47.8, 45.1, 44.5, 13.4. Anal. Calcd for
C
10H10N2O5Cr: C, 41.39; H, 3.47; N, 9.65. Found: C, 41.37;
H, 3.51; N, 9.36.
(CO)5ModCN(CH2CH3)CH2CH2NH (22). A yellow solid
formed (64%): mp 80-81 °C; IR (νCO) 2064, 1927 cm-1 1H
;
NMR δ 5.62 (br, 1 H), 3.70 (q, J ) 7.1 Hz, 2 H), 3.57 (m, 4 H),
1.24 (t, J ) 7.1 Hz, 3 H); 13C NMR δ 213.7 (ModC), 212.0,
206.7, 47.1, 45.8, 44.9, 13.5. Anal. Calcd for C10H10N2O5Mo:
C, 35.95; H, 3.02; N, 8.38. Found: C, 36.17; H, 2.90; N, 8.32.
(CO)5ModCN(CH2CH3)CH2CH2N(CH2CH3) (29). A light
yellow solid formed (73%): mp 92-93 °C [lit.12b mp 93 °C]; IR
1
(νCO) 2063, 1928 cm-1; H NMR δ 3.78 (q, J ) 7.2 Hz, 4 H),
3.53 (s, 4 H), 1.22 (t, J ) 7.2 Hz, 6 H); 13C NMR δ 214.1
(ModC), 212.2, 206.5, 47.6, 46.4, 13.5. Anal. Calcd for
(CO)5WdCN(CH2CH3)CH2CH2NH (23). A yellow solid
formed (96%): mp 96-97 °C; IR (νCO) 2063, 1930 cm-1 1H
;
C
12H14N2O5Mo: C, 39.79; H, 3.90; N, 7.73. Found: C, 39.48;
NMR δ 5.65 (br, 1 H), 3.70 (q, J ) 7.2 Hz, 2 H), 3.57 (m, 4 H),
1.25 (t, J ) 7.2 Hz, 3 H); 13C NMR δ 204.7 (J P-W ) 91.4 Hz)
(WdC), 201.6 (J P-W ) 131.4 Hz), 198.1 (J P-W ) 125.5 Hz), 47.1,
46.6, 45.1, 13.5. Anal. Calcd for C10H10N2O5W: C, 28.46; H,
2.39; N, 6.64. Found: C, 27.95; H, 2.28; N, 6.50.
H, 3.94; N, 7.88.
(CO)5WdCN(CH2CH3)CH2CH2N(CH2CH3) (30). A light
yellow solid (87%): mp 99-100 °C [lit.12c mp 102 °C]; IR (νCO
2062, 1919 cm-1; 1H NMR δ 3.78 (q, J ) 7.2 Hz, 4 H), 3.56 (s,
)
(CO)5WdCN(P h )CH2CH2NH (24). A light yellow solid
(18) Svetlakov, N. V.; Mikheev, V. V.; Fedotov, Yu. A. Zh. Org. Khim.
1971, 7, 2220.
formed (78%): mp 95-96 °C; IR (νCO) 2064, 1926 cm-1 1H
;

1060 Organometallics, Vol. 15, No. 3, 1996
Liu et al.
Ta ble 3. Cr ysta l Da ta for Com p lexes 18 a n d 42
Ta ble 5. Atom ic Coor d in a tes a n d Isoth er m a l
P a r a m eter s (Å2) for 42
compd
x
y
z
Beq
18
42
Re
Br
0.24517(10)
0.1616(3)
0.4373(20)
0.1168(21)
0.4198(23)
0.1303(23)
0.531(3)
0.208(3)
0.221(3)
0.2642(23)
0.407(3)
0.176(3)
0.2687(25)
0.385(3)
0.187(3)
0.7048(21)
0.190(3)
0.2109(24)
0.19503(9)
0.3760(3)
0.4923(20)
0.6176(19)
0.254(3)
0.2354(24)
0.0673(25)
0.184(3)
-0.034(3)
0.4568(20)
0.6830(24)
0.774(3)
0.2323(22)
0.284(3)
0.23993(5)
0.28683(16)
0.1466(12)
0.1465(14)
0.4091(12)
0.4743(11)
0.2061(13)
0.1045(14)
0.3070(14)
0.1734(12)
0.1016(15)
0.1003(17)
0.3878(12)
0.5150(16)
0.5634(14)
0.1853(11)
0.0244(10)
0.3509(11)
2.52(3)
4.35(11)
3.8(8)
formula
fw
cryst syst
space group
temp, K
a, Å
b, Å
c, Å
R, deg
â, deg
γ, deg
V, Å3
C9H8N2O5Mo
320.11
orthorhombic
P212121
C9H12BrN4O3Re
490.33
triclinic
P1h
298
7.355(2)
8.241(3)
13.492(3)
73.32(2)
74.18(3)
63.66(3)
691.9(3)
15.72-37.00
456
N(1)
N(2)
N(3)
N(4)
C(1)
C(2)
C(3)
C(4)
C(5)
C(6)
C(7)
C(8)
C(9)
O(1)
O(2)
O(3)
4.6(8)
4.9(11)
4.3(10)
3.5(9)
4.3(11)
3.9(11)
2.4(8)
3.9(10)
5.0(12)
3.1(8)
5.2(13)
4.5(11)
5.8(8)
298
6.101(3)
13.339(5)
15.557(6)
1266.1(9)
22.60-31.72
632
2θ range, deg
F(000)
Z
0.259(3)
4
2
-0.0121(21)
0.1815(22)
-0.1747(20)
D
calcd, g cm-3
1.679
10.198
ω-2θ
Mo KR
2.354
6.0(10)
5.7(9)
µ, cm-1
117.674
ω-2θ
Mo KR
0.20 × 0.20 × 0.50
scan width
radiation
13.5. Anal. Calcd for C13H14N2O5W: C, 33.79; H, 3.05; N, 6.06.
Found: C, 33.92; H, 2.87; N, 6.02.
cryst dimens, mm
scan width
transm range
2θ max, deg
0.30 × 0.35 × 0.50
2(1.00 + 0.35 tan θ) 2(0.70 + 0.35 tan θ)
0.939; 1.00
50.0
0.787; 1.00
45.0
1804
(CO)5Cr dCN(CH2CHdCH2)CH2CH2N(CH2CHdCH2) (33).
A yellow solid formed (78%): mp 88-89 °C; IR (νCO) 2056, 1923
cm-1; 1H NMR δ 5.82 (m, 2 H), 5.26 (m, 4 H), 4.38 (d, J ) 6.3
Hz, 4 H), 3.46 (s, 4 H); 13C NMR δ 221.7, 220.6 (CrdC), 217.6,
133.2, 119.0 54.5, 48.4. Anal. Calcd for C14H14N2O5Cr: C,
49.13; H, 4.12; N, 8.18. Found: C, 49.16; H, 4.11; N, 8.00.
no. of unique reflns 1316
no. of reflns obsda
1209
1664
computation
soln method
no. of params
R
NRCSDP-VAX
heavy atom
155
NRCSDP-VAX
heavy atom
164
0.025
0.035
Rw
S
0.027
2.77
0.055
2.03
(CO)5ModCN(CH 2CH dCH 2)CH 2CH 2N(CH 2CH dCH 2)
(34). A yellow solid formed (75%): mp 85-87 °C; IR (νCO
)
2064, 1928 cm-1; 1H NMR δ 5.80 (m, 2 H), 5.25 (m, 4 H), 4.36
(d, J ) 6.3 Hz, 4 H), 3.49 (s, 4 H); 13C NMR δ 215.9 (ModC),
211.9, 206.2, 133.2, 118.8, 54.9, 48.3. Anal. Calcd for
a
I > 2σ(I). b R ) ∑|Fo - Fc|/∑(Fo); Rw ) [∑w(Fo - Fc)2/∑(wFo)2]1/2
;
S ) [∑w(Fo - Fc)2/(no. of reflns - no. of params)].
Ta ble 4. Atom ic Coor d in a tes a n d Isoth er m a l
P a r a m eter s (Å2) for 18
C
14H14N2O5Mo: C, 43.54; H, 3.65; N, 7.25. Found: C, 43.93;
H, 3.68; N, 7.20.
x
y
z
Beq
(CO)5WdCN(CH2CHdCH2)CH2CH2N(CH2CHdCH2) (35).
A yellow solid formed (83%): mp 107-108 °C; IR (νCO) 2063,
1924 cm-1; 1H NMR δ 5.81 (m, 2 H), 5.25 (m, 4 H), 4.36 (m, 4
H), 3.51 (s, 4 H); 13C NMR δ 208.0 (J C-W ) 95 Hz) (WdC),
201.1(J C-W ) 129.8 Hz), 197.9 (J C-W ) 125.3 Hz), 133.1, 119.0,
55.8, 48.1. Anal. Calcd for C14H14N2O5W: C, 35.47; H, 2.98;
N, 5.91. Found: C, 35.42; H, 2.95; N, 5.84.
Mo
0.80545(8)
0.6198(11)
1.0234(12)
0.9774(14)
0.9822(12)
0.5832(12)
0.6224(10)
0.4877(15)
0.3532(24)
0.4057(19)
0.6034(10)
0.5245(12)
0.5229(11)
1.1484(9)
0.36484(4)
0.4147(5)
0.4766(5)
0.2809(5)
0.3137(5)
0.2510(5)
0.4660(4)
0.6337(5)
0.5867(6)
0.4915(6)
0.5628(3)
0.4326(4)
0.4392(5)
0.5368(4)
0.2336(4)
0.2832(4)
0.1869(4)
0.20423(3)
0.3037(5)
0.2269(4)
0.2844(5)
0.1035(5)
0.1860(5)
0.1123(4)
0.0683(6)
0.0085(7)
-0.0208(5)
0.1236(3)
0.0430(4)
0.3628(3)
0.2433(3)
0.3328(4)
0.0473(3)
0.1788(4)
3.755(23)
5.6(3)
4.7(3)
5.7(4)
5.5(4)
5.5(4)
3.9(3)
8.8(5)
15.1(9)
9.4(6)
5.7(3)
7.0(4)
9.5(4)
7.5(3)
8.1(3)
8.7(3)
8.2(3)
C(1)
C(2)
C(3)
C(4)
C(5)
C(6)
C(7)
C(8)
C(9)
N(1)
N(2)
O(1)
O(2)
O(3)
O(4)
O(5)
(CO)4Cr dCN(CH2CHdCH2)CH2CH2N(CH2CHdCH2) (36).
Complex 33 (0.3 g, 0.88 mmol) was heated at 90 °C under
vacuum, and the desired product was sublimed and deposited
as a yellow solid (76%): mp 84-85 °C; IR (νCO) 2011, 1910,
1865 cm-1; 1H NMR δ 5.77 (m, 1 H, -CH2CHdCH2), 5.19 (m,
2 H, -CH2CHdCH2), 4.71 (m, 1 H, coord-CH2CHdCH2), 4.14
(dd, J ) 15.4, 5.7 Hz, 1 H, coord-CH2CHdCHH), 3.95 (dd, J )
15.4, 6.4 Hz, 1 H, coord-CH2CHdCHH), 3.68 (m, 2 H), 3.35
(m, 4 H), 3.19 (d, J ) 9 Hz, 1 H), 3.06 (d, J ) 13.2 Hz, 1 H);
13C NMR δ 234.6, 229.5, 227.0, 225.9, 224.0 (CrdC), 133.0
(-CH2CHdCH2), 118.3 (-CH2CHdCH2), 79.7 (coord-
CH2CHdCH2), 63.6 (coord-CH2CHdCH2), 52.9, 50.1, 49.8, 48.2.
Anal. Calcd for C13H14N2O4Cr: C, 49.69; H, 4.49; N, 8.91.
Found: C, 49.31; H, 4.47; N, 8.71.
1.0757(10)
1.0816(10)
0.4640(9)
4 H), 1.23 (t, J ) 7.2 Hz, 6 H); 13C NMR δ 205.6 (WdC), 201.6,
198.0, 47.4, 47.3, 13.4. Anal. Calcd for C12H14N2O5W: C,
32.02; H, 3.14; N, 6.22. Found: C, 31.84; H, 3.03; N, 6.18.
(CO)5WdCN(CH2CH3)CH2CH2N(CH2CCH) (31). A yel-
low solid formed (86%): mp 93-94 °C; IR (νCO) 2064, 1920
cm-1; 1H NMR δ 4.58 (d, J ) 2.5 Hz, 2 H), 3.82 (q, J ) 7.2 Hz,
2 H), 3.64 (m, 4 H), 2.35 (t, J ) 2.5 Hz, 1 H), 1.25 (t, J ) 7.2
Hz, 3 H); 13C NMR δ 207.4 (WdC), 201.1, 197.5, 77.6, 73.9,
47.8, 47.6, 42.8, 13.4. Anal. Calcd for C13H12N2O5W: C, 33.94;
H, 2.63; N, 6.09. Found: C, 33.85; H, 2.46; N, 6.16.
(CO)4ModCN(CH 2CH dCH 2)CH 2CH 2N(CH 2CH dCH 2)
(37). Complex 34 (0.3 g, 0.78 mmol) was heated at 100 °C
under vacuum, and the desired complex 37 was sublimed and
deposited as a yellow solid (85%): mp 72-73 °C [lit.17 mp 67-
1
68 °C]; IR (νCO) 2023, 1920, 1865 cm-1; H NMR δ 5.77 (m, 1
H, -CH2CHdCH2), 5.21 (m, 2 H, coord-CH2CHdCH2), 5.00
(m,1 H, coord-CH2CHdCH2), 4.07 (m, 2 H, -CH2CHdCH2),
3.50 (m, 8 H); 13C NMR δ 223.7, 222.3, 216.2, 212.7, 212.4,
133.0 (-CH2CHdCH2), 118.2 (-CH2CHdCH2), 83.4 (coord-
CH2CHdCH2), 65.8 (CH2CHdCH2), 53.7, 51.1, 49.2, 48.8.
(CO)5WdCN(CH2CH3)CH2CH2N(CH2CdCH2) (32). A yel-
low solid formed (85%): IR (νCO) 2063, 1920 cm-1; H NMR δ
1
5.81 (m, 1 H), 5.26 (m, 2 H), 4.33 (d, J ) 6.1 Hz, 2 H), 3.80 (q,
J ) 7.2 Hz, 2 H), 3.53 (m, 4 H), 1.25 (t, J ) 7.2 Hz, 3 H); 13C
NMR δ 206.7 (J C-W ) 95 Hz) (WdC), 201.4 (J C-W ) 129.8 Hz),
197.9 (J C-W ) 125.7 Hz), 133.1, 118.9, 55.6, 47.9, 47.5, 47.4,
(CO)4WdCN(CH2CHdCH2)CH2CH2N(CH2CHdCH2) (38).
Complex 35 was heated at 110 °C under vacuum to provide

Diamino-Substituted Metal Carbenes
Organometallics, Vol. 15, No. 3, 1996 1061
the desired complex 38 sublimed as a yellow solid (88%): mp
87-88 °C; IR (νCO) 2022, 1918, 1863 cm-1; 1H NMR δ 5.75 (m,
1 H, -CH2CHdCH2), 5.20 (m, 1H, -CH2CHdCH2), 4.66 (m, 1
H, coord-CH2CHdCH2), 3.99 (m, 3 H), 3.73 (dd, J ) 12.0, 4.6
Hz, 1 H, coord-CH2CHdCHH), 3.42 (m, 4 H), 3.17 (m, 2 H);
13C NMR δ 216.7 (J C-W ) 91.4 Hz), 215.5 (J C-W ) 153.1 Hz),
208.3 (J C-W ) 139.4 Hz), 204.4 (J C-W ) 119.9 Hz), 203.8 (J C-W
) 119.6 Hz), 132.8, 118.3, 73.5, 56.1, 54.0, 50.9, 49.2, 48.6.
Anal. Calcd for C13H14N2O4W: C, 35.00; H, 3.16; N, 6.28.
Found: C, 35.01; H, 3.19; N, 6.29.
THF (10 mL) was stirred at 25 °C for 24 h. After concentration
of the reaction mixture, the residue was chromatographed on
silica gel with dichloromethane as the eluent. The eluate was
concentrated to give 42 as a white solid (57%), which was
recrystallized from dichloromethane and hexane to give 42 as
a clear, colorless crystalline solid: mp 133-137 °C (dec); IR
1
(νCO) 2016, 1920, 1852 cm-1; H NMR δ 6.67 (s, 4 H), 3.63 (s,
8 H); 13C NMR δ 202.7, 194.9, 193.9 (RedC), 45.2. Anal. Calcd
for C9H12BrO3N4Re: C, 22.05; H, 2.47; N, 11.43. Found: C,
22.05; H, 2.44; N, 11.27.
Cr ysta llogr a p h y. Single crystals suitable for X-ray analy-
sis of complex 18 and 42 were obtained by slow evaporation
of a solution under air. Cell parameters were determined on
a CAD-4 diffractometer by a least-squares treatment. Atomic
scattering factors were taken from ref 19. Calculations were
performed by using the NRCC SDP VAX package.20 The
crystal data of 18 and 42 are listed in Table 3, and their non-
hydrogen atomic coordinates are listed in Tables 4 and 5,
respectively. Other crystallographic data are collected as
Supporting Information.
(CO)4WdCN(CH 2CH 3)CH 2CH 2N(CH 2CH dCH 2)
(39).
Complex 32 (1.0 g, 2.16 mmol) was placed in a subliming tube.
The apparatus was evacuated and heat to 120 °C. The desired
complex sublimed as a yellow solid (91%): mp 106-107 °C;
IR (νCO) 2021, 1919, 1862 cm-1; 1H NMR δ 4.67 (m, 1 H), 3.91
(dd, J ) 12.1, 1.0 Hz, 1 H), 3.70 (dd, J ) 12.1, 4.6 Hz, 1 H),
3.45 (m, 6 H), 3.20 (m, 2 H), 1.14 (t, J ) 7.2 Hz, 3 H); 13C
NMR δ 216.0 (J C-W ) 91.3 Hz) (WdC), 215.7 (J C-W ) 153.6
Hz), 208.5 (J C-W ) 139.8 Hz), 204.6 (J C-W ) 119.3 Hz), 203.9
(J C-W ) 119.9 Hz), 73.6, 56.1, 50.8, 48.9, 48.6, 46.1, 13.4. Anal.
Calcd for C12H14N2O4W: C, 33.20; H, 3.25; N, 6.45. Found:
C, 33.22; H, 3.07; N, 6.65.
Ack n ow led gm en t. We are grateful for the financial
support of the National Science Council of the Republic
of China (Grant No. NSC 85-2113-M002-17).
Br (CO)4RedCNHCH 2CH2NH (41). A mixture of ReBr-
(CO)5 (300 mg, 0.74 mmol) and 9 (237 mg, 0.74 mmol) in THF
was stirred at 25 °C for 8 h. After removal of solvents, the
residue was chromatographed on silica gel with dichlo-
romethane as the eluent. The eluate was concentrated to give
41 as a white solid (87%): mp 131-134 °C (dec); IR (νCO) 2105,
Su p p or tin g In for m a tion Ava ila ble: Tables giving aniso-
tropic thermal parameters and all bond distances and angles
for 18 and 42 (4 pages). Ordering information is given on any
current masthead page.
1
2003, 1916 cm-1; H NMR δ 6.86 (s, 2 H), 3.72 (s, 4 H); 13C
NMR δ 192.0 (RedC), 186.7, 185.0, 45.3. Anal. Calcd for
C7H6BrO4N2Re: C, 18.76; H, 1.35; N, 6.25. Found: C, 18.75;
H, 1.32; N, 6.31.
OM950735Q
(19) International Tables for X-ray Crystallography; Kynoch Press:
Birmingham, U.K., 1974; Vol. VI.
(20) Gabe, E. J .; Lee, F. L. Acta Crystallogr. 1981, A37, S339.
fa c-Br (CO)3Re[dCNHCH2CH2NH]2 (42). A mixture of
ReBr(CO)5 (300 mg, 0.74 mmol) and 9 (474 mg, 1.48 mmol) in