Insertion reactions of CO into the rhenium-nitrogen bond. η2-Carbamoyl complexes and their reactions

Article abstract of DOI:10.1021/om970544i

Deprotonation of [(CO)₂RReNH(CH₃)CH₂CH₂(η ⁵-C₅H₄)]⁺X^- (R = CO₂Me, CO₂Et; X = Br) followed by heating under a CO atmosphere yields the corresponding CO insertion compound (CO)₂RReC(=O)N(CH₃)CH₂CH₂(η ⁵-C₅H₄). An anologous insertion reaction proceeds more rapidly for the complexes [(CO)₂XReNH(CH₃)CH₂CH₂(η ⁵-C₅H₄)]⁺Y^- (X = Br, I, PhS, and PhSe) in which X is a strong electron-withdrawing group. Without the presence of external ligands, the oxygen of the resultant carbamoyl group binds to the rhenium to fulfill the 18-electron rule. The η²-carbamoyl selenolate complex [(CO)PhSeRe(η²-C=O)N(CH₃)CH₂CH ₂(η⁵-C₅H₄)] (9b) has been characterized by X-ray crystallography. Upon addition of two-electron-donor ligands, such as CO, isocyanides, and trialkyl phosphites, the n²-carbamoyl complexes convert cleanly to the corresponding η¹-carbamoyl complexes.

Full text of DOI:10.1021/om970544i

Organometallics 1998, 17, 131-138
131
Articles
In ser tion Rea ction s of CO in to th e Rh en iu m -Nitr ogen
Bon d . η2-Ca r ba m oyl Com p lexes a n d Th eir Rea ction s
Tein-Fu Wang,* Chong-Chen Hwu, Chia-Wen Tsai, and Yuh-Sheng Wen
Institute of Chemistry, Academia Sinica, Taipei, Taiwan 115, Republic of China
Received J une 27, 1997X
Deprotonation of [(CO)2RReNH(CH3)CH2CH2(η5-C5H4)]+X- (R ) CO2Me, CO2Et; X ) Br)
followed by heating under a CO atmosphere yields the corresponding CO insertion compound
(CO)2RReC(dO)N(CH3)CH2CH2(η5-C5H4). An anologous insertion reaction proceeds more
rapidly for the complexes [(CO)2XReNH(CH3)CH2CH2(η5-C5H4)]+Y- (X ) Br, I, PhS, and PhSe)
in which X is a strong electron-withdrawing group. Without the presence of external ligands,
the oxygen of the resultant carbamoyl group binds to the rhenium to fulfill the 18-electron
rule. The η2-carbamoyl selenolate complex [(CO)PhSeRe(η2-CdO)N(CH3)CH2CH2(η5-C5H4)]
(9b) has been characterized by X-ray crystallography. Upon addition of two-electron-donor
ligands, such as CO, isocyanides, and trialkyl phosphites, the η2-carbamoyl complexes convert
cleanly to the corresponding η1-carbamoyl complexes.
In tr od u ction
electron-donor ligands such as CO, isocyanides, and
trialkyl phosphites. A description of these reactions is
presented herein.
The migratory insertion of carbon monoxide into a
metal-ligand bond is an important reaction.1 The
insertion of carbon monoxide into a metal-carbon bond
has attracted the most attention.2 By comparison, not
much is known about the insertion of carbon monoxide
into a metal-nitrogen bond.3 We are interested in
organometallic complexes that have an amino ligand.4
With certain cationic aminorhenium complexes,5 we
found that removal of a N-H proton by a base results
in migratory insertion of the CO ligand into the rhe-
nium-nitrogen bond. The resultant carbamoyl ligand
binds to the rhenium in an η2-fashion to fulfill the usual
18-electron count. The η2-carbamoyl complexes readily
convert to η1-carbamoyl complexes by adding two-
Resu lts a n d Discu ssion
A. CO In ser tion Rea ction s of th e Am in or h e-
n iu m Com p lexes 2. We reported5 that reaction of 1
with carbon electrophiles provides cationic aminorhe-
nium complexes 2 (see Scheme 1). The N-H proton of
2 could be removed by base to give the corresponding
neutral species 3. Upon exposure to moisture, 3 recap-
tures a proton and regenerates cationic 2. Heating the
neutral complexes 3a -d gave either recovery of 2a -d
or decomposition mixtures. However, when 3e and 3f
were heated, CO insertion occurred, providing 4e and
4f, respectively. In order to improve the yields, the
reactions were performed under a CO atmosphere.
Thus, 2e and 2f were deprotonated with NaH in THF,
followed by heating under 1 atm of CO at 45 oC.
Complexes 4e and 4f were isolated in 70-77% yield.
The terminal CO stretches of 4e and 4f occur as
strong bands at 2029-2030 and 1955-1956 cm-1. The
carbonyl stretches of the ester groups of 4e and 4f were
observed as moderate intensity bands at 1687-1697
cm-1, compared to 1735 cm-1 for the normal ester
groups of organic compounds.5,6 The CO stretch of the
η1-carbamoyl group was observed at 1557-1558 cm-1
as moderate bands. Symmetrical 1H and 13C NMR data
for both 4e and 4f suggests that they are both trans
isomers. The resultant N-methyl of the carbamoyl
X Abstract published in Advance ACS Abstracts, December 15, 1997.
(1) For a review, see: Durfee, L. D.; Rothwell, I. P. Chem. Rev. 1988,
88, 1059.
(2) (a) Conejo, M. M.; Pizzano, A.; Sanchez, L. J .; Carmona, E. J .
Chem. Soc., Dalton Trans. 1996, 3687. (b) Gomez, M.; Gomez-Sal, P.;
J imenez, G.; Martin, A.; Royo, P.; Sanchez-Nieves, J . Organometallics
1996, 15, 3579. (c) Contreras, L.; Pizzano, A.; Sanchez, L.; Carmona,
E. J . Organomet. Chem. 1995, 500, 61. (d) Giannini, L.; Solari, E.;
Angelis, S. D.; Ward, T. R.; Floriani, C.; Chiesi-Villa, A.; Rizzoli, C. J .
Am. Chem. Soc. 1995, 117, 5801. (e) Angelis, S. D.; Solari, E.; Floriani,
C.; Chiesi-Villa, A.; Rizzoli, C. Organometallics 1995, 14, 4505. (f)
Gamble, A. S.; White, P. S.; Templeton, J . L. Organometallics 1991,
10, 693.
(3) (a) Rahim, M.; Ahmed, K. J . Organometallics 1994, 13, 1751.
(b) Chisholm, M. H.; Hammond, C. E.; Huffman, J . C. Organometallics
1987, 6, 210. (c) Ahmed, K. J .; Chisholm, M. H. Organometallics 1986,
5, 185. (d) Fagan, P. J .; Manriquez, J . M.; Vollmer, S. H.; Day, C. S.;
Day, V. W.; Marks, T. J . J . Am. Chem. Soc. 1981, 103, 2206.
(4) (a) Wang, T. F.; Lai, C. Y.; Wen, Y. S. J . Organomet. Chem. 1996,
523, 187. (b) Wang, T. F.; Wen, Y. S. J . Organomet. Chem. 1992, 439,
155. (c) Wang, T. F.; Lee, C. Y.; Wen, Y. S.; Liu, L. K. J . Organomet.
Chem. 1991, 403, 353.
(6) Silverstein, R. M.; Bassler, G. C.; Morrill, T. C. Spectroscopic
Identification of Organic Compounds, 5th ed.; J ohn Wiley & Sons: New
York, 1991; pp 113-123.
(5) Wang, T. F.; Lai, C. Y.; Hwu, C. C.; Wen, Y. S. Organometallics
1997, 16, 1218.
S0276-7333(97)00544-X CCC: $15.00 © 1998 American Chemical Society
Publication on Web 01/19/1998

132 Organometallics, Vol. 17, No. 2, 1998
Wang et al.
Sch em e 1
Sch em e 2
Sch em e 3
group was observed at δ 3.00 as a singlet for both
compounds, compared to a doublet for the N-methyl
group of 2. Complexes derived from the CO insertion
into the Re-R bonds were not observed in the reactions.
B. In ser tion Rea ction s of th e Am in or h en iu m
Ha lid es 5. In view of the ease of the CO insertion for
3e and 3f relative to that for 3a -d , we felt that the
insertion reaction may have something to do with the
nature of the R group. It seemed that the more electron-
negative the R group, the faster the insertion of CO into
the Re-N bond. In order to test this, we studied the
reactions of the halides 5a and 5b, which contain much
more electronegative groups compared to the ester
groups of 2e and 2f.
Complex 1 reacted readily with Br2 and I2, providing
the bromide 5a and iodide 5b in nearly quantitative
yield (see Scheme 2). Formation of the cationic halides
5a and 5b could be easily characterized by the terminal
CO stretches in the IR. Upon halogenation, the CO
stretches shift from 1893 and 1816 cm-1 for 1 to 2069
and 2001 cm-1 for 5a and 2058 and 1992 cm-1 for 5b.
As a result of the electron-withdrawing nature of the
halide ligand, the N-H protons of 5a and 5b are quite
acidic and a weak base, such as Et3N, is strong enough
to remove it. Slow addition of Et3N to each individual
CH2Cl2 solution of 5a and 5b resulted in an immediate
disappearance of the terminal carbonyl absorptions and
the concomitant appearance of two new carbonyl bands.
One band is due to a terminal CO (1905 cm-1) and the
other band (1642 cm-1) is associated with the carbamoyl
1
stretch. In the H NMR spectra, the Cp protons of both
products moved upfield relative to that for 5a and 5b
and the N-methyl groups were observed as singlets at
δ 3.31 and δ 3.34, respectively. These spectroscopic data
suggest that the reaction products are the η2-carbamoyl
complexes 6a and 6b. Complexes 6a and 6b decom-
posed slowly in solution, and attempts of recrystalliza-
tion were unsuccessful.
Upon exposure to CO, 6a and 6b converted to η1-
carbamoyl complexes 7a and 7b. Two terminal carbonyl

Insertion Reactions of CO into the Re-N Bond
Organometallics, Vol. 17, No. 2, 1998 133
F igu r e 1. ORTEP drawing of 7a .
F igu r e 2. ORTEP drawing of 9b.
streches were observed at 2052 and 1982 cm-1 for 7a
and at 2042 and 1972 cm-1 for 7b. The carbamoyl
absorption occurred at 1569 cm-1 for 7a and 1570 cm-1
for 7b. In the 1H NMR spectra, four Cp protons
displayed as an AA′BB′ pattern at δ 5.88 and 5.78 for
7a and δ 5.75 and 5.49 for 7b. The 13C NMR spectra of
both 7a and 7b showed that the two terminal carbonyls
are identical (δ 188.5 for 7a ; δ 186.8 for 7b) and the Cp
1
carbons are symmetrical. The symmetrical H and 13C
data suggests that 7a and 7b are both trans isomers.
Definite assignment of 7a has been accomplished by an
X-ray analysis. Figure 1 shows that the two terminal
carbonyls are in a trans orientation with an angle of
102° (C10-Re-C11). The trans Br and the η1-carbamoyl
define an angle of 138° (Br-Re-C8).
F igu r e 3. ORTEP drawing of 10ba . There are two
essentially independent molecules within the unit cell. Only
one molecule is shown.
C. η2-Ca r ba m oyl Com p lexes of Rh en iu m Sele-
n ola te a n d Rh en iu m Th iola te. In addition to carbon
and halogen electrophiles, we also examined the reac-
tions of 1 with electrophiles derived from the group 16
elements. Rhenium-sulfur and rhenium-selenium
bonds7 were formed easily via the reaction of 1 with
phenylsulfenyl chloride (PhSCl) and phenylselenenyl
bromide (PhSeBr), respectively. The reactions pro-
ceeded instantly, providing 8a and 8b in nearly quan-
titative yield (see Scheme 3). Terminal carbonyl stretches
appearing at 2052 and 1986 cm-1 for 8a and 2042 and
1978 cm-1 for 8b are characteristic for this type of
complex.5 Addition of Et3N to a CH2Cl2 solution of 8a
resulted in an immediate disappearance of the terminal
carbonyl absorptions and the concomitant appearance
of a new intense band at 1900 cm-1 and a medium band
at 1605 cm-1 that are associated with the η2-carbamoyl
complex 9a . Reaction of 8b with Et3N proceeded
similarly, providing the η2-carbamoyl complex 9b. The
N-methyl groups of 9a and 9b appeared as singlets at
molecular structure of 9b (Figure 2) shows that the
carbamoyl group binds to the rhenium in an η2-mode
with bond distances of 2.01 Å for Re-C8 and 2.37 Å for
Re-O8. The rhenium-carbon bond distance is 0.18 Å
shorter than that for the η1-carbamoyl 5a (2.19 Å for
Re-C8) and 0.20 Å shorter for the η1-carbamoyl 10ba
(2.21 Å for Re-C8, see below). The CO bond length for
the η2-carbamoyl group of 9b is 1.26 Å, not much
different from those for the η1-carbamoyls 5a (1.22 Å)
and 10ba (1.22 Å, see below).
D. Con ver sion of η2-Ca r ba m oyl Com p lexes t o
η1-Ca r ba m oyl Com p lexes by Ad d ition of Tw o-
Electr on -Don or Liga n d s. When CO gas was intro-
duced into individual solutions of 9a and 9b, dicarbonyl
complexes 10a a and 10ba were obtained (see Scheme
3). Formation of 10a a and 10ba could be easily
characterized by the terminal carbonyl stretches. Two
carbonyl stretches observed at 2036 and 1966 cm-1 for
10a a and 2027 and 1959 cm-1 for 10ba are character-
istic of this type of dicarbonyl complex. Symmetrical
1H and 13C NMR data suggest that 10a a and 10ba are
trans isomers. Figure 3 shows the molecular structure
of 10ba . Two terminal carbonyl groups are in a trans
orientation with an angle of 99.1°. The angle of the
selenolate and the carbamoyl groups is 137.9°. It is
worth noting that the atoms attached to the carbamoyl
group, namely, C1, C9, N1, C8, O8, and Re1, lie in the
same plane. Similarly, in 7a , the C1, C9, N, C8, O8,
and Re atoms are essentially planar.
1
δ 3.26 and 3.23 in the H NMR spectra, similar to those
for 6a and 6b. Remarkably, η2-carbamoyl complexes 9a
and 9b are quite stable and could be purified chromato-
graphically with silica gel.
A single crystal of 9b was obtained from a solution of
CH2Cl2 in hexane and analyzed by crystallography. The
(7) Preparation of transition-metal selenolate complexes have been
reported, see: (a) Eikens, W.; J ager, S.; J ones, P. G.; Thone, C. J .
Organomet. Chem. 1996, 511, 67. (b) Eikens, W.; Kienitz, C.; J ones,
P. G.; Thone, C. J . Chem. Soc., Dalton Trans. 1994, 3329. (c) Lau, P.;
Huttner, G.; Zsolnai, L. J . Organomet. Chem. 1992, 440, 41. (d) Winter,
A.; Huttner, G.; Gottlieb, M.; J ibril, I. J . Organomet. Chem. 1985, 286,
317.
Addition of tert-butyl isocyanide to a solution of 9a
and 9b resulted in immediate coordination of isocyanide
to the rhenium, providing 10a b and 10bb, respectively.

134 Organometallics, Vol. 17, No. 2, 1998
Wang et al.
Strong bands appearing at 2156 cm-1 for 10a b and 2150
cm-1 for 10bb are characteristic of an isocyanide
stretch. A strong and a medium band at 1954 and 1554
cm-1 for 10a b and 1947 and 1553 cm-1 for 10bb are
assigned to the terminal carbonyl and the η1-carbamoyl
stretches, respectively.
Exp er im en ta l Section
Reactions that required anhydrous conditions were per-
formed under an argon atmosphere by means of Schlenk-tube
techniques. Infrared solution spectra were recorded on a
Perkin-Elmer 882 infrared spectrophotometer using 0.1 mm
cells with CaF2 windows. Melting points were determined by
using a Yanaco model MP micro melting point apparatus and
were uncorrected. 1H NMR (300 MHz) and 13C NMR (75 MHz)
were obtained with a Bruker AC-300 FT spectrophotometer.
For the assignment of the 1H and 13C NMR data, the carbon
bound to the nitrogen was designated as C1 and the hydrogens
on C1 were designated as H1a and H1b. The next carbon was
designated as C2 and the hydrogens on C2 were designated as
In addition to CO and isocyanide, trialkyl phosphites
also add to η2-carbamoyl 9a and 9b to give the corre-
sponding η1-carbamoyl complexes 10 (L ) P(OR)3).
Addition of P(OMe)3 or P(OEt)3 to a solution of 9a
resulted in an immediate color change from red to
yellow. The terminal carbonyl stretch shifted from 1900
to 1935 cm-1 for 10a c and to 1930 cm-1 for 10a d .
Incorporation of a phosphite ligand was verified by 31P
chemical shifts, which appeared at δ 93.0 for 10a c and
δ 88.4 for 10a d . The reaction of 9b with phosphites
proceeded similarly to that for 9a . Phosphite complexes
with thiolate 10a c and 10a d are not stable in solution
and slowly decomposed to an unidentifiable mixture.
The corresponding selenolate complexes 10bc and 10bd
are much more labile than the thiolate complexes 10a c
and 10a d , converting via an unclear pathway to 11a
and 11b with a half-life of about 5 min at room
temperature. Complexes 11a and 11b were character-
ized spectroscopically. In the infrared spectra, two
terminal carbonyl stretchings appeared with equal
intensities at 1941 and 1868 cm-1 for 11a and 1938 and
1866 cm-1 for 11b and the coordinated phosphite ligand
was observed at δ 140.1 for 11a and δ 136.2 for 11b.
H2a and H2b
. All chemical shifts are reported in parts per
million (ppm) relative to Me4Si. Elemental analyses were
obtained on a Perkin-Elmer 2400 CHN elemental analyzer.
Mass spectra were recorded on a VG 70-250S mass spectro-
photometer.
P r epar ation of (CO)2RReC(dO)N(CH3)CH2CH2(η5-C5H4)
(4e, R ) CH2CO2Me; 4f, R ) CH2CO2Et). A two-necked, 100
mL flask equipped with a stir bar was charged with NaH (95
mg, 60% dispersion in mineral oil). Mineral oils were removed
by washing 3 times with hexane under nitrogen. Nitrogen was
evacuated and replaced with CO gas. THF (20 mL) was then
added. A suspension of 2e or 2f (0.55 mmol) in THF (20 mL)
was added at room temperature over 5 min. The resultant
mixture was heated in an oil bath at 45 °C for 16 h. The
mixture was then filtered through Celite. The filtrates were
concentrated and chromatographed on silica gel, using 50%
ethyl acetate in hexane as the eluent followed by 100% ethyl
acetate. A pale yellow band was collected and concentrated
to give 4e or 4f.
(CO)2(CH2CO2Me)ReC(dO)N(CH3)CH2CH2(η5-C5H4) (4e):
yellow crystal (77% yield). Mp: 141-144 °C. IR (CH2Cl2):
Con clu sion
2030 (s), 1956 (s), 1697(m), 1558 (m) cm-1 1H NMR (CDCl3,
.
Removal of the N-H proton of cationic aminorhenium
complexes results in a CO insertion into the Re-N bond,
as demonstrated by the halides 5a ,b, thiolate 8a , and
selenolate 8b. The resultant carbamoyl group binds to
the Re in an η2-mode. Remarkably, η2-carbamoyl
complexes 9a and 9b are stable, as shown by their
stability toward column chromatography. In the pres-
ence of two-electron-donor ligands, such as CO, isocya-
nides, and phosphites, the η2-carbamoyl complexes
readily convert to the corresponding η1-carbamoyl com-
plexes. The nature of the R group affects the insertion
reaction. For complexes that having a strong electron-
withdrawing R group, such as 5a , 5b, 8a , and 8b, the
insertion reaction proceeds rapidly at low temperature
(0 °C). When R is an ester group, such as 2e and 2f,
the insertion reaction requires a higher temperature (45
°C) and longer time (several hours). No insertion
reactions were observed when the R group was alkyl,
allyl, benzyl, and propargyl (2a -d ).
From these results, it can be concluded that two
conditions are required for the insertion reaction: re-
moval of the N-H proton and an electron-withdrawing
R group. Removal of the N-H proton results in a free
electron-pair on the nitrogen. This may allow the
resultant nonbonding electrons of the nitrogen to in-
teract with the nearby CO ligand. The electron-
withdrawing nature of the R group may lower the π*
orbital of the CO ligand, thereby reducing the energy
gap between the π* orbital of CO and the nonbonding
orbital of the nitrogen. This may account for the rapid
reaction of 5a , 5b, 8a , and 8b, slow reaction of 2e and
2f, and nonreactivity of 2a -d .
300 MHz): δ 5.41 (2H, t, J ) 2.0 Hz, Cp H), 5.36 (2H, t, J )
2.0 Hz, Cp H), 3.62 (3H, s, OCH3), 3.36 (2H, t, J ) 5.4 Hz),
3.00 (3H, s, N-CH3), 2.40 (2H, s, Re-CH2CO2Me), 2.35 (2H,
t, J ) 5.5 Hz). 13C NMR (CDCl3, 75 MHz): δ 193.9 (CO × 2),
182.0 (C, CO2Me), 173.3 (C, ReCON), 106.5 (C, Cp), 94.3 (CH
× 2, Cp), 86.7 (CH × 2, Cp), 59.9 (CH2, C1), 50.8 (CH3, OCH3),
34.8 (CH3, N-CH3), 25.5 (CH2, C2), -17.9 (CH2, Re-CH2CO2-
Me). MS (FAB, 187Re; m/ e (relative intensity)): 465 (60, M+),
409 (95), 392 (60), 367 (100), 336 (85). Anal. Calcd for
C
14H16NO5Re: C, 36.20; H, 3.47; N, 3.02. Found: C, 36.15;
H, 3.35; N, 2.84.
(CO)2(CH2CO2Et)ReC(dO)N(CH3)CH2CH2(η5-C5H4) (4f):
yellow crystal (70% yield). Mp: 116-118 °C. Rf ) 0.36 (100%
EtOAc, SiO2). IR (CH2Cl2): 2029 (s), 1955 (s), 1687 (m), 1557
(m) cm-1 1H NMR (CDCl3, 300 MHz): δ 5.39 (2H, t, J ) 2.0
.
Hz, Cp H), 5.36 (2H, t, J ) 2.0 Hz, Cp H), 4.07 (2H, q, J ) 7.1
Hz, OEt), 3.36 (2H, t, J ) 5.5 Hz, H1), 3.00 (3H, s, N-CH3),
2.39 (2H, s, Re-CH2CO2Et), 2.34 (2H, t, J ) 5.5 Hz, H2), 1.26
(3H, t, J ) 7.1 Hz, OEt). 13C NMR (CDCl3, 75 MHz): δ 193.9
(CO × 2), 181.4 (C, CO2Et), 173.4 (C, ReCON), 106.5 (C, Cp),
94.2 (CH × 2, Cp), 86.6 (CH × 2, Cp), 59.9 (CH2), 59.5 (CH2),
34.7 (CH3, N-CH3), 25.4 (CH2, C2), 14.2 (CH3, OEt), -17.7
(CH2, Re-CH2CO2Et). MS (FAB, 187Re; m/ e (relative inten-
sity)): 480 (80, M+ + 1), 423 (88), 392 (100, M+ - CH2CO2Et),
364 (82), 336 (70). Anal. Calcd for C15H18NO5Re: C, 37.65;
H, 3.79; N, 2.93. Found: C, 37.68; H, 3.69; N, 2.79.
P r epar ation of [(CO)2XReNH(CH3)CH2CH2(η5-C5H4)]+X-
(5a , X ) Br ; 5b, X ) I). A 100 mL flask was charged with
aminorhenium complex 1 (364 mg, 1 mmol) followed by CH2-
Cl2 (20 mL) and pyridine (0.2 mL). The resultant yellow
solution was cooled in an ice-water bath. A CH2Cl2 solution
of halogen (0.25 M for Br2 or 0.04 M for I2, 1 mmol) was added
over 5-10 min. After the mixture was stirred for an additional
5 min, hexane (5 mL) was added. The volume of the solvents
was reduced to about 10-15 mL by evaporation under reduced

Insertion Reactions of CO into the Re-N Bond
Organometallics, Vol. 17, No. 2, 1998 135
pressure. The resultant red precipitates were collected and
washed twice with ether to give red powders of 5a (82%) or
5b (92%). 5a and 5b are stable in the solid state. While in
solution, they decomposed gradually at room temperature.
[(CO)2Br ReNH(CH3)CH2CH2(η5-C5H4)]+Br - (5a): red crys-
tal (82% yield). Mp: 100-103 °C. IR (CH2Cl2): 2069 (s), 2001
[(CO)2Br ReC(dO)N(CH3)CH2CH2(η5-C5H4)] (7a ): orange
crystal (78% yield). Mp: 125-130 °C. Rf ) 0.46 (100% EtOAc,
SiO2). IR (CH2Cl2): 2052 (s), 1982 (s), 1569 (m) cm-1 1H NMR
.
(C3D6O, 300 MHz): δ 5.88 (2H, t, J ) 2.2 Hz, Cp H), 5.78 (2H,
t, J ) 2.2 Hz, Cp H), 3.45-3.41 (2H, m), 2.87 (3H, s, N-CH3),
2.46-2.42 (2H, m). 1H NMR (CDCl3, 300 MHz): δ 5.68 (2H,
t, J ) 2.2 Hz, Cp H), 5.55 (2H, t, J ) 2.2 Hz, Cp H), 3.44-3.40
(2H, m), 2.98 (3H, s, N-CH3), 2.36-2.32 (2H, m). 13C NMR
(CDCl3, 75 MHz): δ 188.5 (CO × 2), 168.0 (C, Re-CON), 104.9
(C, Cp), 98.3 (CH × 2, Cp), 86.5 (CH × 2, Cp), 60.2 (CH2, C1),
35.1 (CH3, N-CH3), 25.2 (CH2, C2). MS (FAB, 187Re; m/ e
(relative intensity)): 473 (45, M+), 445 (38, M+ - CO), 417
(50, M+ - 2CO), 392 (100, M+ - Br), 364 (35, M+ - Br - CO),
336 (25, M+ - I - 2CO). Anal. Calcd for C11H11BrNO3Re: C,
28.03; H, 2.35; N, 2.97. Found: C, 28.25; H, 2.38; N, 2.62.
[(CO)2IR eC(dO)N(CH3)CH2CH 2(η5-C5H 4)] (7b ): orange
crystal (85% yield). Mp: 122-125 °C (dec). Rf ) 0.47 (100%
(s) cm-1 1H NMR (CDCl3, 300 MHz): δ 9.83 (1H, br, N-H),
.
7.52 (1H, br s, Cp H), 6.56 (1H, br s, Cp H), 5.85 (1H, br s, Cp
H), 5.41 (1H, br s, Cp H), 4.45-4.38 (1H, m, H1a), 3.48-3.38
(1H, m, H1b), 3.15-3.04 (1H, m, H2a), 2.99 (3H, d, J ) 5.6 Hz,
N-CH3), 2.24-2.16 (1H, m, H2b). MS (FAB, 81Br, 187Re; m/e
(relative intensity)): 446 (12, M+). Anal. Calcd for
C
10H12Br2NO2Re: C, 22.91; H, 2.31; N, 2.67. Found: C, 22.66;
H, 2.49; N, 2.32.
[(CO)2IReNH(CH3)CH2CH2(η5-C5H4)]+I- (5b): red crystal
(92% yield). Mp: 126 °C (dec). IR (CH2Cl2): 2058 (s), 1992
(s) cm-1 1H NMR (CDCl3, 300 MHz): δ 8.79 (1H, br, N-H),
.
EtOAc, SiO2). IR (CH2Cl2): 2042 (s), 1972 (s), 1570 (m) cm-1
.
7.34 (1H, br s, Cp H), 6.34 (1H, br s, Cp H), 5.94 (1H, br s, Cp
H), 5.72 (1H, br s, Cp H), 4.47-4.40 (1H, m, H1a), 3.50-3.37
(1H, m, H1b), 3.28-3.15 (1H, m, H2a), 2.98 (3H, d, J ) 5.7 Hz,
N-CH3), 2.27-2.21 (1H, m, H2b). 1H NMR (CD3OD, 300
MHz): δ 6.84 (1H, br s, Cp H), 6.62 (1H, br s, Cp H), 6.02
(1H, br s, Cp H), 5.99 (1H, br s, Cp H), 4.19-4.12 (1H, m, H1a),
3.81-3.72 (1H, m, H1b), 3.06 (3H, s, N-CH3), 2.44-2.36 (2H,
m, H2). MS (FAB, 187Re; m/ e (relative intensity)): 492 (52,
M+), 365 (12, M+ - I). Anal. Calcd for C10H12I2NO2Re: C,
19.43; H, 1.96; N, 2.26. Found: C, 19.68; H, 2.05; N, 2.02.
P r ep a r a tion of [(CO)XRe(η2-CdO)N(CH3)CH2CH2(η5-
C5H4)] (6a ,b; X ) Br , I). To a stirred yellow solution of 1
(364 mg, 1 mmol) in CH2Cl2 (20 mL) at 0 °C was added a CH2-
Cl2 solution of halogen (0.25 M for Br2 or 0.04 M for I2, 1 mmol)
over 5-10 min. After the mixture was stirred for an additional
5 min, a solution of triethylamine (0.3 mL) in CH2Cl2 (10 mL)
was then added slowly over 1 h by using a syringe pump. The
cool bath was removed, and the red solution was concentrated.
The resultant red solids were washed three 3 with ether. The
residue was then extracted with THF twice to give a red liquid
1H NMR (C3D6O, 300 MHz): δ 5.75 (2H, t, J ) 2.2 Hz, Cp H),
5.49 (2H, t, J ) 2.2 Hz, Cp H), 3.46-3.42 (2H, m), 3.02 (3H, s,
N-CH3), 2.38-2.34 (2H, m). 1H NMR (CDCl3, 300 MHz): δ
5.75 (2H, t, J ) 2.2 Hz, Cp H), 5.50 (2H, t, J ) 2.2 Hz, Cp H),
3.46-3.42 (2H, m), 3.02 (3H, s, N-CH3), 2.39-2.35 (2H, m).
13C NMR (CDCl3, 75 MHz): δ 186.8 (CO × 2), 166.0 (C, Re-
CON), 105.6 (C, Cp), 95.0 (CH × 2, Cp), 86.5 (CH × 2, Cp),
60.0 (CH2, C1), 35.3 (CH3, N-CH3), 25.4 (CH2, C2). MS (FAB,
187Re; m/ e (relative intensity)): 520 (80, M+ + 1), 491 (52, M+
- CO), 463 (60, M+ - 2CO), 392 (100, M+ - I), 364 (38, M+
I - CO), 336 (28, M+ - I - 2CO). Anal. Calcd for C11H11
-
-
INO3Re: C, 25.49; H, 2.14; N, 2.70. Found: C, 25.40; H, 2.08;
N, 2.59.
P r ep a r a t ion of [(CO)2P h XR eNH (CH 3)CH 2CH 2(η5-
C5H4)]+Y- (8a , X ) S, Y ) Cl; 8b, X ) Se, Y ) Br ). A CH2-
Cl2 solution of PhSCl (0.2 M, 5 mL) or PhSeBr (0.2 M, 5 mL)
was added to a stirred yellow solution of 1 (364 mg, 1 mmol)
in CH2Cl2 (20 mL) at 0 °C over 5 min. After the mixture was
stirred for an additional 5 min, the resultant red solution was
concentrated under reduced pressure to about 3 mL. The
residual solution was then added slowly to ether (60 mL). The
precipitates were collected and washed twice with ether to give
8a or 8b.
1
after evaporation (70-80% yield). The H NMR spectra of the
liquid showed that it contained 85% of 6 and 15% of 7. Small
amounts of pure samples of 6a and 6b were obtained,
respectively, by recrystallization of the each individual mixture
mentioned above from a solution of CH2Cl2 and hexane.
[(CO)Br Re(η2-CdO)N(CH3)CH2CH2(η5-C5H4)] (6a ): red
powder. Mp: 113 °C (dec). IR (CH2Cl2): 1905 (s), 1642 (m)
[(CO)2P h SReNH(CH3)CH2CH2(η5-C5H4)]+Cl- (8a ): hy-
groscopic orange powder (98% yield). IR (CH2Cl2): 2052(s),
1986 (s) cm-1
.
1H NMR (CDCl3, 300 MHz): δ 10.0 (1H, br,
cm-1 1H NMR (C3D6O, 300 MHz): δ 6.07-6.05 (m, 1H, Cp
.
N-H), 7.32-7.25 (5H, m, Ph), 7.17-7.15 (1H, m, Cp H), 6.43-
6.41 (1H, m, Cp H), 5.65-5.63 (1H, m, Cp H), 5.33-5.31 (1H,
m, Cp H), 4.27-4.22 (1H, m, H1a), 3.40-3.32 (1H, m, H1b),
3.14-3.04 (1H, m, H2a), 3.01 (3H, d, J ) 5.5 Hz, N-CH3), 2.26
(1H, dd, J ) 13.2, 6.3 Hz, H2b). 13C NMR (CDCl3, 75 MHz): δ
191.8 (CO), 189.1 (CO), 140.2 (C, Ph), 132.4 (CH × 2, Ph), 128.6
(CH × 2, Ph), 126.9 (C, Cp), 126.0 (CH, Ph), 99.7 (CH, Cp),
92.3 (CH, Cp), 91.2 (CH, Cp), 88.3 (CH, Cp), 77.4 (CH2, C1),
48.5 (CH3, N-CH3), 24.4 (CH2, C2). MS (FAB, 187Re; m/ e
(relative intensity)): 474 (52, M+), 446 (100, M+ - CO), 365
(25, M+ - SPh). Anal. Calcd for C16H17ClNO2ReS: C, 37.75;
H, 3.37; N, 2.75. Found: C, 37.28; H, 3.51; N, 2.47.
H), 5.80-5.78 (m, 1H, Cp H), 5.41-5.39 (m, 1H, Cp H), 5.04-
5.02 (m, 1H, Cp H), 3.69 (1H, ddd, J ) 13.9, 4.1, 3.0 Hz, H1a),
3.56 (1H, ddd, J ) 13.9, 12.4, 2.3 Hz, H1b), 3.31 (3H, s, N-CH3),
2.92 (1H, dt, J ) 14.3, 2.6 Hz, H2a), 2.53 (1H, ddd, J ) 14.3,
12.4, 4.1 Hz, H2b). Anal. Calcd for C10H11BrNO2Re: C, 27.09;
H, 2.50; N, 3.16. Found: C, 26.82; H, 2.48; N, 2.95.
[(CO)IRe(η2-CdO)N(CH3)CH2CH2(η5-C5H4)] (6b): orange
crystal. Mp: 117-118 °C (dec). IR (CH2Cl2): 1905 (s), 1642
(m) cm-1 1H NMR (CDCl3, 300 MHz): δ 6.14-6.12 (m, 1H,
.
Cp H), 5.68-5.66 (m, 1H, Cp H), 5.15-5.13 (m, 1H, Cp H),
4.83-4.81 (m, 1H, Cp H), 3.68-3.49 (2H, m), 3.34 (3H, s,
N-CH3), 2.86 (1H, dt, J ) 14.4, 2.5 Hz, H2a), 2.38 (1H, ddd, J
) 14.4, 12.4, 4.3 Hz, H2b). MS (FAB, 187Re; m/ e (relative
intensity)): 492 (10, M+ + 1), 463 (10, M+ - CO). Anal. Calcd
for C10H11INO2Re: C, 24.50; H, 2.26; N, 2.86. Found: C, 24.46;
H, 2.28; N, 2.62.
P r ep a r a t ion of [(CO)2XR eC(dO)N(CH 3)CH 2CH 2(η5-
C5H4)] (7a , X ) Br ; 7b, X ) I). The procedure is similar to
that for the preparation of 6 except that a carbon monoxide
gas was bubbling through a needle while adding the triethyl-
amine solution. After concentration, the residue was flash-
chromatographed on silica gel with 50% ethyl acetate in
hexane as the eluent followed by 100% ethyl acetate. The first
orange band was collected and concentrated to give 7a or 7b.
Analytical pure samples were obtained by recrystallization of
the individual complex from dichloromethane and hexane.
[(CO)2P h SeReNH(CH3)CH2CH2(η5-C5H4)]+Br - (8b): hy-
groscopic orange powder (99% yield). IR (CH2Cl2): 2042 (s),
1978 (s) cm-1
.
1H NMR (CDCl3, 300 MHz): δ 9.32 (1H, br,
N-H), 7.46-7.40 (2H, m, Ph), 7.29-7.24 (3H, m, Ph), 7.16-
7.14 (1H, m, Cp H), 6.29-6.27 (1H, m, Cp H), 5.55-5.53 (1H,
m, Cp H), 5.42-5.40 (1H, m, Cp H), 4.29-4.22 (1H, m, H1a),
3.43-3.30 (1H, m, H1b), 3.15 (1H, td, J ) 12.8, 6.1 Hz, H2a),
3.01 (3H, d, J ) 5.7 Hz, N-CH3), 2.22 (1H, dd, J ) 13.3, 6.1
Hz, H2b). 13C NMR (CDCl3, 75 MHz): δ 191.5 (CO), 189.0 (CO),
135.1 (CH × 2, Ph), 129.9 (C, Ph or Cp), 128.9 (CH × 2, Ph),
128.1 (C, Cp or Ph), 127.6 (CH, Ph), 96.8 (CH, Cp), 91.0 (CH,
Cp), 89.4 (CH, Cp), 87.5 (CH, Cp), 77.9 (CH2, C1), 48.8 (CH3,
N-CH3), 24.5 (CH2, C2). Anal. Calcd for C16H17BrNO2ReSe:
C, 32.01; H, 2.85; N, 2.33. Found: C, 31.67; H, 2.98; N, 2.30.
P r ep a r a tion of [(CO)P h XRe(η2-CdO)N(CH3)CH2CH2-

136 Organometallics, Vol. 17, No. 2, 1998
Wang et al.
(η5-C5H4)] (9a , X ) S; 9b, X ) Se). A solution of triethylamine
(0.3 mL) in CH2Cl2 (3 mL) was added over 3 min to a stirred
solution of 8a or 8b (1 mmol) in CH2Cl2 (25 mL) at 0 °C. The
cool bath was removed. After the mixture was stirred at room
temperature for 10 min, the solution was concentrated and
the residue was flash-chromatographed on silica gel with 50%
ethyl acetate in hexane as the eluent followed by 90% ethyl
acetate in hexane. A red band was collected and concentrated
to give 9a or 9b.
intensity)): 501 (12, M+). Anal. Calcd for C17H16NO3ReS: C,
40.79; H, 3.22; N, 2.80. Found: C, 41.11; H, 3.27; N, 2.68.
[(C O )((C H 3)3C N C )P h S R e C (dO )N (C H 3)C H 2C H 2(η5-
C5H4)] (10a b): yellow crystal (94% yield). Mp: 115-119 °C
(dec). IR (CH2Cl2): 2156 (m), 1954 (s), 1554 (m) cm-1
.
1H
NMR (CDCl3, 300 MHz): δ 7.37-7.33 (2H, m, Ph), 7.14-7.09
(2H, m, Ph), 6.98-6.93 (1H, m, Ph), 5.53-5.51 (1H, m, Cp H),
5.41-5.39 (1H, m, Cp H), 5.38-5.36 (1H, m, Cp H), 5.29-5.27
(1H, m, Cp H), 3.55-3.38 (2H, m), 2.98 (3H, s, N-CH3), 2.46
(1H, ddd, J ) 13.4, 7.0, 3.5 Hz, H2a), 2.22 (1H, ddd, J ) 13.4,
7.5, 3.8 Hz, H2b), 1.26 (9H, s, tBu). 13C NMR (CDCl3, 75
MHz): δ 197.4 (CO), 176.9 (CO, ReCON), 144.5 (C, Ph), 135.9
(C, ReCNtBu), 131.9 (CH × 2, Ph), 127.5 (CH × 2, Ph), 122.8
(CH, Ph), 103.8 (C, Cp), 99.5 (CH, Cp), 92.8 (CH, Cp), 87.4
[(CO)P h SRe(η2-CdO)N(CH3)CH2CH2(η5-C5H4)] (9a ): red
crystal (63% yield). Mp: 112-115 °C (dec). IR (CH2Cl2): 1900
(s), 1605 (w) cm-1 1H NMR (CDCl3, 300 MHz): δ 7.44-7.40
.
(2H, m, Ph), 7.21-7.14 (2H, m, Ph), 7.08-7.02 (1H, m, Ph),
5.53-5.51 (1H, m, Cp H), 5.27-5.25 (1H, m, Cp H), 5.11-5.09
(1H, m, Cp H), 4.76-4.74 (1H, m, Cp H), 3.53 (1H, ddd, J )
13.8, 12.2, 2.2 Hz, H1a), 3.43 (1H, ddd, J ) 13.8, 3.9, 3.2 Hz,
t
(CH, Cp), 83.6 (CH, Cp), 59.5 (CH2, C1), 57.4 (C, Bu), 34.7
(CH3, N-CH3), 30.2 (CH3 × 3, tBu), 25.9 (CH2, C2). Anal. Calcd
for C21H25N2O2ReS: C, 45.39; H, 4.53; N, 5.04. Found: C,
45.76; H, 4.79; N, 4.81.
H
1b), 3.26 (3H, s, N-CH3), 2.86 (1H, dt, J ) 14.2, 2.7 Hz, H2a),
2.33 (1H, ddd, J ) 14.2, 12.2, 3.9 Hz, H2b). 13C NMR (CDCl3,
75 MHz): δ 207.8 (CO), 199.1 (CO), 153.0 (C, Ph), 132.5 (CH
× 2, Ph), 127.6 (CH × 2, Ph), 124.9 (CH, Ph), 109.9 (C, Cp),
104.2 (CH, Cp), 96.9 (CH, Cp), 74.4 (CH, Cp), 69.5 (CH, Cp),
55.1 (CH2, C1), 36.2 (CH3, N-CH3), 28.2 (CH2, C2). MS (FAB,
187Re; m/ e (relative intensity)): 474 (85, M+ + 1), 445 (38, M+
- CO), 364 (20, M+ - SPh). Anal. Calcd for C16H16NO2ReS:
C, 40.66; H, 3.41; N, 2.96. Found: C, 40.74; H, 3.47; N, 2.80.
[(CO)P h SeRe(η2-CdO)N(CH3)CH2CH2(η5-C5H4)] (9b): or-
ange crystal (65% yield). Mp: 120 °C (dec). Rf ) 0.70 (100%
[(CO)(P (OMe)3)P h SReC(dO)N(CH3)CH2CH2(η5-C5H4)]
(10a c): unstable yellow crystal (95% yield). Mp: 118-124 °C
(dec). IR (CH2Cl2): 1935 (s), 1577 (w), 1550 (w) cm-1 1H NMR
.
(CDCl3, 300 MHz): δ 7.45-7.41 (2H, m, Ph), 7.16-7.11 (2H,
m, Ph), 7.04-6.98 (1H, m, Ph), 5.62-5.60 (1H, m, Cp H), 5.38-
5.36 (1H, m, Cp H), 5.24-5.22 (1H, m, Cp H), 5.20-5.18 (1H,
m, Cp H), 3.78 (9H, d, J ) 11.5 Hz, P(OMe)3), 3.40-3.35 (2H,
m), 2.94 (3H, s, N-CH3), 2.61-2.54 (1H, m, H2a), 2.05-2.00
(1H, m, H2b). 31P NMR (CDCl3): δ 93.0. Anal. Calcd for
EtOAc, SiO2). IR (CH2Cl2): 1897 (s), 1610 (m) cm-1 1H NMR
.
C
19H25NO5PReS: C, 38.25; H, 4.22; N, 2.35. Found: C, 38.02;
H, 4.08; N, 2.32.
(CDCl3, 300 MHz): δ 7.56-7.52 (2H, m), 7.18-7.09 (3H, m),
5.45-5.43 (m, 1H, Cp H), 5.23-5.21 (m, 1H, Cp H), 5.14-5.12
(m, 1H, Cp H), 4.68-4.66 (m, 1H, Cp H), 3.60 (1H, td, J )
13.2, 2.1 Hz, H1a), 3.46 (1H, dt, J ) 13.6, 3.4 Hz, H1b), 3.29
(3H, s, N-CH3), 2.85 (1H, dt, J ) 14.2, 2.4 Hz, H2a), 2.35 (1H,
ddd, J ) 14.2, 12.6, 3.8 Hz, H2b). 1H NMR (CD3CN, 300
MHz): δ 7.44-7.40 (2H, m, Ph), 7.16-7.08 (3H, m, Ph), 5.63-
5.61 (m, 1H, Cp H), 5.26-5.24 (m, 1H, Cp H), 5.18-5.16 (m,
1H, Cp H), 4.69-4.67 (m, 1H, Cp H), 3.57-3.52 (2H, m), 3.23
(3H, s, N-CH3), 2.81 (1H, dt, J ) 14.2, 2.4 Hz, H2a), 2.40 (1H,
ddd, J ) 14.2, 12.6, 3.8 Hz, H2b). 13C NMR (CDCl3, 75 MHz):
δ 205.4 (CO), 199.1 (CO), 142.8 (C, Ph), 134.1 (CH × 2, Ph),
127.5 (CH × 2, Ph), 125.0 (CH, Ph), 109.9 (C, Cp), 102.9 (CH,
Cp), 96.2 (CH, Cp), 72.7 (CH, Cp), 69.5 (CH, Cp), 55.0 (CH2,
C1), 36.2 (CH3, N-CH3), 28.0 (CH2, C2). Anal. Calcd for
C16H16NO2ReSe: C, 36.99; H, 3.10; N, 2.70. Found: C, 37.05;
H, 3.02; N, 2.61.
[(CO)(P (OE t )3)P h SR eC(dO)N(CH 3)CH 2CH 2(η5-C5H 4)]
(10a d ): unstable yellow crystal (82% yield). Mp: 92-94 °C
(dec). IR (CH2Cl2): 1930 (s), 1577 (w), 1548 (w), 1472 (w) cm-1
.
1H NMR (CDCl3, 300 MHz): δ 7.43-7.37 (2H, m, Ph), 7.15-
7.09 (2H, m, Ph), 7.02-6.97 (1H, m, Ph), 5.57-5.55 (1H, m,
Cp H), 5.27-5.25 (2H, m, Cp H), 5.18-5.16 (1H, m, Cp H),
4.24-4.06 (6H, m, OEt), 3.39-3.31 (2H, m), 2.91 (3H, s,
N-CH3), 2.52-2.45 (1H, m, H2a), 2.09 (1H, ddd, J ) 13.2, 9.2,
4.5 Hz, H2b), 1.37-1.22 (9H, m, OEt). 31P NMR (CDCl3): δ
88.4. MS (FAB, 187Re; m/ e (relative intensity)): 640 (10, M+
+ 1), 611 (35, M+ - CO), 530 (100, M+ - SPh), 502 (80, M+
SPh - CO). Anal. Calcd for C22H31NO5PReS: C, 41.37; H,
4.89; N, 2.19. Found: C, 41.37; H, 4.96; N, 2.12.
-
Rea ction of 9b w ith L (L ) CO, (CH3)3CNC, P (OMe)3,
P (OEt)3). The respective procedures are analogous to the
preparation of 10a a -a d . Complexes 10bc and 10bd are
hygroscopic and unstable at room temperature. They readily
converted to 11a and 11b, respectively, in solution with a room
temperature with a half-life of about 5 min.
P r ep a r a tion of [(CO)(L)P h SReC(dO)N(CH3)CH2CH2-
(η5-C5H4)] (10a a -a d (L ) CO, (CH3)3CNC, P (OMe)3, P (O-
Et)3). For L ) CO, the CO gas was allowed to bubble through
a CH2Cl2 solution of 9a (236 mg, 0.5 mmol) at 0 °C until the
1900 cm-1 absorption disappeared in the IR spectrum. For L
) (CH3)3CNC, P(OMe)3, and P(OEt)3, a CH2Cl2 solution of L
(1 equiv) was added to a stirred red solution of 9a (236 mg,
0.5 mmol) in CH2Cl2 (20 mL) at 0 °C over 2 min. After the
mixture was stirred for another 2 min, the CO stretch of 9a
(1900 cm-1) disappeared. Hexane (10 mL) was added to the
resultant yellow solution and then evaporated under reduced
pressure to about 5 mL of solvents. Yellow precipitates were
collected and washed twice with hexane to give 10a a -a d .
Analytically pure samples were obtained by recrystallization
of the individual compound from dichloromethane and hexane.
[(CO)2P h SReC(dO)N(CH3)CH2CH2(η5-C5H4)] (10aa): yel-
low crystal (100% yield). Mp: 121-124 °C (dec). IR (CH2-
[(CO)2P h SeReC(dO)N(CH 3)CH2CH2(η5-C5H4)] (10ba ):
orange crystal (98% yield). Mp: 140 °C (dec). Rf ) 0.46 (100%
EtOAc, SiO2). IR (CH2Cl2): 2027 (s), 1959 (s), 1567 (m) cm-1
.
1H NMR (CDCl3, 300 MHz): δ 7.53-7.49 (2H, m), 7.19-7.13
(3H, m), 5.57 (2H, t, J ) 2.2 Hz, Cp H), 5.38 (2H, t, J ) 2.2
Hz, Cp H), 3.40 (2H, t, J ) 5.5 Hz, H1’s), 3.01 (3H, s, N-CH3),
2.33 (2H, t, J ) 5.5 Hz, H2’s). 13C NMR (CDCl3, 75 MHz): δ
190.0 (CO), 170.0 (CO, ReCON), 135.2 (CH × 2, Ph), 131.9 (C,
Ph), 128.4 (CH × 2, Ph), 126.4 (CH, Ph), 106.7 (C, Cp), 96.4
(CH × 2, Cp), 86.7 (CH × 2, Cp), 60.2 (CH2, C1), 34.9 (CH3,
N-CH3), 25.4 (CH2, C2). Anal. Calcd for C17H16NO3ReSe: C,
37.30; H, 2.94; N, 2.56. Found: C, 37.58; H, 2.90; N, 2.42.
[(CO)((CH 3)3CNC)P h Se R e C(dO)N(CH 3)CH 2CH 2(η5-
C5H4)] (10bb): yellow crystal (95% yield). Mp: 60 °C (dec).
Cl2): 2036 (s), 1966 (s), 1567 (m) cm-1
.
1H NMR (CDCl3, 300
IR (CH2Cl2): 2150 (s), 1947 (s), 1553 (m), 1472 (m) cm-1 1H
.
MHz): δ 7.38-7.34 (2H, m, Ph), 7.21-7.14 (2H, m, Ph), 7.11-
7.05 (1H, m, Ph), 5.59 (2H, t, J ) 2.2 Hz, Cp H), 5.49 (2H, t,
J ) 2.2 Hz, Cp H), 3.42 (2H, t, J ) 5.5 Hz), 2.99 (3H, s,
N-CH3), 2.35 (2H, t, J ) 5.5 Hz). 13C NMR (CDCl3, 75 MHz):
δ 190.0 (CO), 171.1 (CO, ReCON), 142.1 (C, Ph), 133.1 (CH ×
2, Ph), 128.1 (CH × 2, Ph), 124.9 (CH, Ph), 106.8 (C, Cp), 98.2
(CH × 2, Cp), 86.9 (CH × 2, Cp), 60.3 (CH2, C1), 34.9 (CH3,
N-CH3), 25.3 (CH2, C2). MS (FAB, 187Re; m/ e (relative
NMR (CDCl3, 300 MHz): δ 7.52-7.47 (2H, m), 7.13-7.03 (3H,
m), 5.39-5.36 (2H, m, Cp H), 5.33-5.31 (1H, m, Cp H), 5.20-
5.18 (1H, m, Cp H), 3.48 (1H, ddd, J ) 13.8, 7.3, 3.7 Hz, H1a),
3.40 (1H, ddd, J ) 13.8, 7.1, 3.7 Hz, H1b), 3.00 (3H, s, N-CH3),
2.39 (1H, ddd, J ) 13.4, 7.3, 3.7 Hz, H2a), 2.24 (1H, ddd, J )
t
13.4, 7.1, 3.7 Hz, H2b), 1.31 (9H, s, Bu). 13C NMR (CDCl3, 75
MHz): δ 197.3 (CO), 175.5 (CO, ReCON), 135.6 (C, ReCNtBu),
134.2 (C, Ph), 133.7 (CH × 2, Ph), 127.8 (CH × 2, Ph), 124.3

Insertion Reactions of CO into the Re-N Bond
Organometallics, Vol. 17, No. 2, 1998 137
Ta ble 1. Cr ysta llogr a p h ic Da ta a n d Str u ctu r e Refin em en ts for 7a , 9b, a n d 10ba
compound
formula
fw
7a
9b
10ba
C34H32N2O6Re2Se2
1094.97
C
11H11BrNO3Re
C16H19NO2ReSe
522.50
471.32
cryst size (mm)
cryst syst
space group
a (Å)
b (Å)
c (Å)
R (deg)
â (deg)
γ (deg)
V (Å3)
0.41 × 0.38 × 0.28
0.25 × 0.13 × 0.13
monoclinic
P21/a
11.3724(11)
8.2498(7)
17.3955(19)
90
99.787(9)
90
1608.3(3)
4
0.26 × 0.19 × 0.19
triclinic
triclinic
P1h
P1h
6.8954(12)
9.4283(9)
10.2745(12)
102.620(10)
93.576(12)
107.518(11)
615.7(1)
7.7076(13)
9.4299(14)
23.1581(23)
90.513(10)
90.879(11)
93.963(13)
1678.9(4)
2
Z
2
Dc (g cm-3
F(000)
)
2.542
433
2.158
988
2.166
1032
λ(Mo KR) (Å)
µ(Mo KR) (cm-1
transmissn
0.710 69
132.129
0.841; 1.000
2.06-8.24
2(0.70 + 0.35 tan θ)
45.0
25; 14.75-32.73
-7 to 7, 0 to 10, -11 to 10
1770
0.710 69
99.028
0.829; 1.000
1.65-8.24
2(0.70 + 0.35 tan θ)
50.0
25; 14.72-34.38
-13 to 13, 0 to 9, 0 to 20
2925
0.710 69
94.959
)
0.869; 1.000
1.65-8.24
2(0.75 + 0.35 tan θ)
45.0
25; 14.84-33.44
-8 to 8, 0 to 10, -24 to 24
4770
scan speed (deg min-1
θ/2θ scan width (deg)
2θmax (deg)
)
unit cell detn: no.; 2θ range (deg)
hkl range
no. of collected reflns
no. of unique reflns
1608
2827
4376
no. of obsd reflns (I > 2.0σ(I))
1528
154
0.031; 0.041
2.91
0.000 100
+0.800; -1.880
1635
190
0.036, 0.037
1.16
0.000 100
+0.840; -0.800
3658
415
0.025, 0.031
1.62
0.000 100
+0.720; -1.190
no. of refined params
b
Rf;a Rw
GOF
2
weight modifier k in kFo
∆F (max, min; e Å-3
)
a
b
2 1/2
Rf ) ∑(Fo - Fc)/∑(Fo). Rw ) [∑w(Fo - Fc)2/∑wFo
] .
Ta ble 2. Selected Bon d Len gth s (Å) a n d Bon d
An gles (d eg) for 7a , 9b, a n d 10ba
(CH, Ph), 103.6 (C, Cp), 97.0 (CH, Cp), 92.0 (CH, Cp), 86.9
t
(CH, Cp), 83.2 (CH, Cp), 59.2 (CH2, C1), 57.3 (C, Bu), 34.6
(CH3, N-CH3), 30.2 (CH3 × 3, tBu), 25.8 (CH2, C2). Anal. Calcd
for C21H25N2O2ReSe: C, 41.86; H, 4.18; N, 4.65. Found: C,
42.08; H, 4.32; N, 4.55.
7a
9b
10ba
Re-Br(Se)
2.613(1)
2.19(1)
2.500(2)
2.02(1)
2.37(1)
1.88(1)
2.591(1)
2.213(9)
Re-C(8)
[(C O )(P (O M e )3 )P h S e R e C (dO )N (C H 3 )C H 2 C H 2 (η5 -
C5H 4)] (10b c): unstable hygroscopic yellow powder. IR
Re-O(8)
Re-C(10)
1.93(1)
1.95(1)
1.22(1)
1.93(1)
1.93(1)
1.22(1)
Re-C(11)
(CH2Cl2): 1933 (s) cm-1 1H NMR (CDCl3, 300 MHz): δ 7.58-
.
C(8)-O(8)
1.26(1)
121.2(4)
89.2(2)
90.0(4)
7.54 (2H, m, Ph), 7.12-7.09 (3H, m, Ph), 5.36-5.34 (2H, m,
Cp H), 5.29-5.27 (1H, m, Cp H), 5.15-5.13 (1H, m, Cp H),
3.77 (9H, d, J ) 11.5 Hz, P(OMe)3), 3.38-3.34 (2H, m), 2.95
(3H, s, N-CH3), 2.56-2.48 (1H, m, H2a), 2.16-1.99 (1H, m,
Br(Se)-Re-C(8)
Br(Se)-Re-O-(8)
Br(Se)-Re-C(10)
Br(Se)-Re-C(11)
Re-C(8)-O(8)
O(8)-Re-C(8)
O(8)-Re-C(10)
C(8)-Re-C(10)
C(8)-Re-C(11)
C(10)-Re-C(11)
Cp(cent.)-Re-Br(Se)
Cp(cent.)-Re-C(8)
Cp(cent.)-Re-O(8)
Cp(cent.)-Re-C(10)
Cp(cent.)-Re-C(11)
138.7(3)
137.9(2)
77.8(3)
80.2(4)
121.7(8)
76.2(3)
77.8(3)
120.6(7)
H
2b). 31P NMR (CDCl3): δ 99.8.
[(C O )(P (O E t )3 )P h S e R e C (dO )N (C H 3 )C H 2 C H 2 (η5 -
89.8(8)
32.0(4)
92.3(4)
90.7(5)
C5H 4)] (10b d ): unstable hygroscopic yellow powder. IR
73.3(4)
77.8(5)
102.0(4)
111.53(4)
109.7(3)
74.0(4)
78.3(4)
99.1(4)
112.46(3)
109.6(2)
(CH2Cl2): 1927 (s) cm-1 1H NMR (CDCl3, 300 MHz): δ 7.57-
.
7.53 (2H, m, Ph), 7.12-7.09 (3H, m, Ph), 5.36 (1H, s, Cp H),
5.25 (1H, s, Cp H), 5.23 (1H, s, Cp H), 5.15 (1H, s, Cp H), 4.19-
4.06 (6H, m, P(OEt)3), 3.38-3.31 (2H, m), 2.92 (3H, s, N-CH3),
2.48-2.42 (1H, m, H2a), 2.12-2.03 (1H, m, H2b), 1.36 (9H, t, J
) 7.2 Hz, P(OEt)3). 31P NMR (CDCl3): δ 98.0.
117.14(4)
109.9(3)
131.8(2)
124.7(3)
134.5(3)
123.3(3)
136.5(3)
124.3(3)
(CO)2(P (OMe)3)Re(η5-C5H4CH2CH2N(CH3)SeP h ) (11a ):
yellow liquid (92% yield from 9b). IR (CH2Cl2): 1941 (s), 1868
(s) cm-1
.
1H NMR (CDCl3, 300 MHz): δ 7.63-7.59 (2H, m,
135.5 (C, Ph), 131.5 (CH × 2, Ph), 129.1 (CH × 2, Ph), 127.7
(CH, Ph), 105.3 (C, Cp), 82.4 (CH × 2, Cp), 82.2 (CH × 2, Cp),
61.0 (CH2 × 3, P(OEt)3), 53.7 (CH2), 36.1 (CH3, N-CH3), 28.6
(CH2), 16.0 (CH3 × 3, P(OEt)3). 31P NMR (CDCl3): δ 136.2.
Anal. Calcd for C22H31NO5PReSe: C, 38.54; H, 4.56; N, 2.04.
Found: C, 358.28; H, 4.39; N, 2.32.
Cr ystal Str u ctu r es of [(CO)2Br ReC(dO)N(CH3)CH2CH2-
(η5-C5H4)] (7a ), [(CO)P h SeRe(η2-CdO)N(CH3)CH2CH2(η5-
C5H4)] (9b), a n d [(CO)2P h SeReC(dO)N(CH3)CH2CH2(η5-
C5H4)] (10ba ). Single crystals of 7a , 9b, and 10ba were
obtained from each individual solution of CH2Cl2 and hexane
at 5 °C for several days. Diffraction measurements were made
on an Enraf-Nonius CAD-4 automated diffractometer by use
of a graphite-monochromated Mo KR radiation (λ ) 0.710 69
Å) with the θ-2θ scan mode. The unit cells were determined
Ph), 7.28-7.24 (3H, m, Ph), 5.13 (2H, t, J ) 2 Hz, Cp H), 5.05
(2H, t, J ) 2 Hz, Cp H), 3.54 (9H, d, J ) 12.4 Hz, P(OMe)3),
2.75 (2H, t, J ) 6.8 Hz), 2.59 (2H, d, J ) 6.8 Hz), 2.46 (3H, s,
N-CH3). 31P NMR (CDCl3): δ 140.1. Anal. Calcd for
C
19H25NO5PReSe: C, 35.46; H, 3.92; N, 2.18. Found: C, 35.58;
H, 3.96; N, 2.05.
(CO)2(P (OEt)3)Re(η5-C5H4CH2CH2N(CH3)SeP h ) (11b):
yellow liquid (93% yield from 9b). IR (CH2Cl2): 1938 (s), 1866
(s) cm-1
.
1H NMR (CDCl3, 300 MHz): δ 7.64-7.58 (2H, m,
Ph), 7.33-7.24 (3H, m, Ph), 5.09 (2H, t, J ) 2 Hz, Cp H), 5.02
(2H, t, J ) 2 Hz, Cp H), 3.90 (6H, dq, J ) 14.6, 7.2 Hz,
P(OEt)3), 2.73 (2H, t, J ) 7.5 Hz), 2.57 (2H, d, J ) 7.5 Hz),
2.44 (3H, s, N-CH3), 1.29 (9H, t, J ) 7.2 Hz, P(OEt)3). 13C
NMR (CDCl3, 75 MHz): δ 200.8 (CO × 2, d, J CP ) 35 Hz),

138 Organometallics, Vol. 17, No. 2, 1998
Wang et al.
2
and refined using 25 randomly selected reflections obtained
with the automatic search, center, index, and least-squares
routines. Lorentz/polarization and empirical absorption cor-
rections based on three azimuthal scans were applied to the
data. The space groups (P1h for 7a and 10ba ; P21/a for 9b)
were determined from the systematic absences observed
during data collection. All data reduction and refinements
were carried out on a DecAlpha 3400/400 computer using the
NRCVAX program.8 The structures were solved by direct
methods and refined by a full-matrix least-squares routine9
with anisotropic thermal parameters for all non-hydrogen
Fc| , where w ) (1/σ2)Fo was calculated from the counting
statistics. Hydrogens were included in the structure factor
calculations in their expected positions on the basis of idealized
bonding geometry but not refined in least-squares. The final
cell parameters and data collection parameters are listed in
Table 1, and selected bond distances and angles in Table 2.
Ack n ow led gm en t. We are grateful to the National
Science Council of Taiwan, ROC, for financial support.
atoms. The structures were refined by minimizing ∑w|Fo
-
Su p p or tin g In for m a tion Ava ila ble: Tables of data col-
lection parameters, bond lengths and bond angles, fractional
atomic coordinates, and anisotropic thermal parameters for
7a , 9b, and 10ba (11 pages). Ordering information is given
on any current masthead page.
(8) Gabe, E. J .; LePage, Y.; Charland, J . P.; Lee, F. L; White, P. S.
J . Appl. Crystallogr. 1989, 22, 384.
(9) Main, P. In Crystallographic Computing 3: Data Collection,
Structure Determination, Proteins and Databases, Sheldrick, G. M.,
Krueger, C., Goddard, R., Eds.; Clarendon Press: Oxford, 1985; pp
206-215.
OM970544I