A R T I C L E S
Dias et al.
NMR (C6D12) coordinated 3-hexyne signals: 91.3 (s, EtCt CEt),
14.4, 12.3. 19F NMR (C6D12): δ -81.26 (triplet, 6F, JFF ) 10.8
Hz, CF3), -106.02 (quartet, 4F, JFF ) 10.8 Hz, R-CF2), -122.55
6.9 Hz, CH(CH3)2), 1.14 (d, 12H, J ) 6.9 Hz, CH(CH3)2), 0.80 (br
quartet, 4H, C2CH2CH3), 0.76 (br triplet, 6H, C2CH2CH3). 13C{1H}
NMR (C6D12) coordinated 3-hexyne signals: 99.2 (s, EtCt CEt),
15.4, 13.5. 19F NMR (C6D12): δ -81.22 (triplet, 6F, JFF ) 10.8
Hz, CF3), -105.58 (quartet, 4F, JFF ) 10.8 Hz, R-CF2), -122.31
1
(s, 4F, ꢀ-CF2). H NMR (CDCl3): δ 7.04 (s, 6H, m,p-Ar), 3.11
(septet, 4H, J ) 6.9 Hz, CH(CH3)2), 1.23 (d, 12H, J ) 6.9 Hz,
CH(CH3)2), 1.13 (d, 12H, J ) 6.9 Hz, CH(CH3)2), 1.04 (quartet,
4H, J ) 7.4 Hz, C2CH2CH3), 0.79 (triplet, 6H, J ) 7.4 Hz,
C2CH2CH3). 13C{1H} NMR (CDCl3) selected: 90.3 (s, EtCt CEt).
19F NMR (CDCl3): δ -80.34 (triplet, 6F, JFF ) 10.1 Hz, CF3),
-105.64 (quartet, 4F, JFF ) 10.1 Hz, R-CF2), -122.19 (s, 4F,
ꢀ-CF2). Anal. Calcd for C38H44N3F14Au: C, 45.38; H, 4.41; N, 4.18.
Found: C, 45.90; H, 4.71; N, 4.16. IR (Nujol, cm-1) selected: 1923
(m, Ct C); IR (KBr, cm-1): 1924 (m, Ct C). Raman (cm-1): 1920
(m, Ct C). Crystals of [N{(C3F7)C(Dipp)N}2]Au(EtCt CEt) are air
and light stable for well over 24 h. A solution of the title compound
in CDCl3 is also stable for more than 24 h under darkness at room
temperature.
1
(s, 4F, ꢀ-CF2). H NMR (CDCl3): δ 7.05 (s, 6H, m,p-Ar), 3.02
(septet, 4H, J ) 6.9 Hz, CH(CH3)2), 1.23 (d, 12H, J ) 6.9 Hz,
CH(CH3)2), 1.10 (d, 12H, J ) 6.9 Hz, CH(CH3)2), 0.75 (br singlet,
4H, CH2CH3), 0.75 (br singlet, 6H, CH2CH3). 13C{1H} NMR
(CDCl3) selected: 98.2 (s, EtCt CEt). 19F NMR (CDCl3): δ -80.31
(triplet, 6F, JFF ) 10.7 Hz, CF3), -105.20 (quartet, 4F, JFF ) 10.7
Hz, R-CF2), -121.96 (s, 4F, ꢀ-CF2). Anal. Calcd for C38H44-
N3F14Cu: C, 52.32; H, 5.08; N, 4.82. Found: C, 52.57; H, 5.12; N,
4.82. IR (Nujol, cm-1) selected: 2045 (vw), 2008 (w); IR (KBr,
cm-1) selected: 2044 (vw), 2007 (w). Raman bands in the
1750-2500 region (cm-1): 2003 (w, Ct C), 2039 vw. Crystals are
air and light stable for more than 24 h. These show no decomposi-
tion at -20 °C under inert atmosphere in the presence of n-hexane
after 1 week. A solution of the title compound in CDCl3 darkens
after 12 h at room temperature.
X-ray Crystallographic Data. X-ray quality crystals of 5-7
were obtained from hexane solutions at -20 °C. A suitable crystal
covered with a layer of hydrocarbon/paratone-N oil was selected
and mounted on a Cryo-loop, and immediately placed in the low-
temperature nitrogen stream. The X-ray intensity data were
measured at 100(2) K on a Bruker SMART APEX CCD area
detector system equipped with a Oxford Cryosystems 700 series
cooler, a graphite monochromator, and a Mo KR fine-focus sealed
tube (λ ) 0.710 73 Å). The data frames were integrated with the
Bruker SAINT-Plus (version 6.45) software package. Structures
were solved and refined using Bruker SHELXTL (version 6.14)
software package. All the non-hydrogen atoms were refined
anisotropically. Hydrogen atoms were placed at calculated positions
and refined riding on the corresponding carbons. The CCDC
731649, 73150, and 731651 contain the supplementary crystal-
lographic data for compounds 7 (copper adduct), 6 (silver adduct),
and 5 (gold adduct), respectively. Some of these data are given in
Tables S1-6, Supporting Information.
[N{(C3F7)C(Dipp)N}2]Ag(EtCt CEt) (6). [N{(C3F7)C(Dipp)-
N}2]Li (0.32 mmol) was dissolved in n-hexane (15 mL), and
3-hexyne (0.04 mL, 0.32 mmol) was added using a syringe. This
solution was cooled to -10 °C and transferred to a flask containing
AgOTf (0.082 g, 0.32 mmol). The mixture was stirred for 20 min
at <5 °C (it is important to maintain the low temperature; longer
stirring times should also be avoided as it leads to darker solutions,
perhaps indicating some decomposition). It was filtered over a bed
of Celite, and the filtrate was collected and concentrated to ∼1 mL
at 0 °C by passing a nitrogen stream. The resulting solution was
cooled at -20 °C to obtain [N{(C3F7)C(Dipp)N}2]Ag(EtCt CEt)
as pale-yellow crystals in about 6 h. The solution was removed
using a syringe, and the crystals were separated and dried under
reduced pressure. Yield: 72%, Mp: changes color at 109 °C, darkens
at 121 °C, melted 163-166 °C (dec).1H NMR (C6D12): δ 6.98 (d,
4H, 7.8 Hz, m -Ar), 6.90 (t, 2H, 7.8 Hz, p-Ar), 3.21 (septet, 4H, J
) 6.9 Hz, CH(CH3)2), 1.25 (d, 12H, J ) 6.9 Hz, CH(CH3)2), 1.17
(d, 12H, J ) 6.9 Hz, CH(CH3)2), 0.98 (quartet, 4H, J ) 6.9 Hz,
C2CH2CH3), 0.74 (triplet, 6H, J ) 6.9 Hz, C2CH2CH3). 13C{1H}
NMR (C6D12) coordinated 3-hexyne signals: 80.6 (s, EtCt CEt),
14.8, 13.2. 19F NMR (C6D12): δ -81.32 (triplet, 6F, JFF ) 9.0 Hz,
CF3), -106.36 (quartet, 4F, JFF ) 9.0 Hz, R-CF2), -122.68 (s, 4F,
Crystal Data of [N{(C3F7)C(Dipp)N}2]Au(EtCt CEt) (5).
Empirical formula C38H44AuF14N3, FW ) 1005.73, Temp ) 100(2)
1
ꢀ-CF2). H NMR (CDCl3): δ 7.03 to 6.95 (m, 6H, m,p-Ar), 3.14
j
K, Crystal system ) Triclinic, Space gp ) P1, a ) 9.0868(3) Å,
(septet, 4H, J ) 6.9 Hz, CH(CH3)2), 1.24 (d, 12H, J ) 6.9 Hz,
CH(CH3)2), 1.14 (d, 12H, J ) 6.9 Hz, CH(CH3)2), 0.92 (br, 4H,
C2CH2CH3), 0.75 (apparent triplet, 6H, C2CH2CH3). 13C{1H} NMR
(CDCl3) selected: 80.9 (s, EtCt CEt). 19F NMR (CDCl3): δ -80.41
(triplet, 6F, JFF ) 10.1 Hz, CF3), -105.96 (quartet, 4F, JFF ) 10.1
Hz, R-CF2), -122.31 (s, 4F, ꢀ-CF2). Anal. Calcd for C38H44
N3F14Ag: C, 49.79; H, 4.84; N, 4.58. Found: C, 50.01; H, 4.77; N,
b ) 12.6753(5) Å, c ) 17.8359(7) Å, R ) 82.848(1)°, ꢀ )
78.796(1)°, γ ) 80.426(1)°, Volume ) 1978.04(13) Å3, Z ) 2,
Final R indices [I > 2σ(I)] R1 ) 0.0320, wR2 ) 0.0864; R indices
(all data) R1 ) 0.0323, wR2 ) 0.0866.
Crystal Data of [N{(C3F7)C(Dipp)N}2]Ag(EtCt CEt) (6).
Empirical formula C38H44AgF14N3, FW ) 916.63, Temp ) 100(2)
j
4.58. IR (Nujol, cm-1) selected: 2105 (weak); IR (KBr, cm-1
)
K, Crystal system ) Triclinic, Space gp ) P1, a ) 9.1356(6) Å,
selected: 2122-2104 (weak br). Raman (cm-1): 2104 (w, Ct C).
Crystals of [N{(C3F7)C(Dipp)N}2]Ag(EtCt CEt) are air and light
stable for more than 24 h. Darkening is observed after about 3 days.
No decomposition was observed for more than 2 weeks at -20 °C
under inert atmosphere in the presence of n-hexane. However, the
product decomposes slowly in CDCl3 even in the dark at room
temperature, as evident from the formation of a black solid.
[N{(C3F7)C(Dipp)N}2]Cu(EtCt CEt) (7). [N{(C3F7)C(Dipp)N}2]
Li (0.32 mmol) was dissolved in n-hexane (15 mL), and 3-hexyne
(0.04 mL, 0.32 mmol) was added via a syringe. This solution was
cooled at 0 °C and then transferred to a flask containing (CuOTf)2 ·
benzene (0.081 g, 0.16 mmol). The mixture was stirred for 90 min
at 5 °C (the solution turned cloudy). The stirring was stopped, and
the solution was filtered over a bed of Celite. The filtrate was
collected and concentrated to ∼1 mL at 5 °C by slow evaporation
under reduced pressure. It was cooled at -20 °C to obtain yellow-
greenish crystals of [N{(C3F7)C(Dipp)N}2]Cu(EtCt CEt) overnight.
The supernatant was removed using a syringe, and the crystals were
dried under reduced pressure. Yield: 80%, Mp: darkens at 133 °C,
melted 140-147 °C (dec).1H NMR (C6D12): δ 7.01 (m, 6H, m,p-
Ar), 3.09 (septet, 4H, J ) 6.9 Hz, CH(CH3)2), 1.24 (d, 12H, J )
b ) 12.7961(9) Å, c ) 17.7376(12) Å, R ) 82.756(1)°, ꢀ )
78.647(1)°, γ ) 80.038(1)°, Volume ) 1993.2(2) Å3, Z ) 2, Final
R indices [I > 2σ(I)] R1 ) 0.0333, wR2 ) 0.0852; R indices (all
data) R1 ) 0.0355, wR2 ) 0.0869.
Crystal Data of [N{(C3F7)C(Dipp)N}2]Cu(EtCt CEt) (7).
Empirical formula C38H44CuF14N3, FW ) 872.30, Temp ) 100(2)
j
K, Crystal system ) Triclinic, Space gp ) P1, a ) 9.1036(3) Å,
b ) 12.5604(5) Å, c ) 17.6485(6) Å, R ) 81.606(1)°, ꢀ )
79.605(1)°, γ ) 80.286(1)°, Volume ) 1942.49(12) Å3, Z ) 2,
Final R indices [I > 2σ(I)] R1 ) 0.0379, wR2 ) 0.0997; R indices
(all data) R1 ) 0.0414, wR2 ) 0.1025.
Computational Study. Density functional calculations were
performed using the B3LYP functional as implemented in Gaussian
03.45 We choose cc-pVDZ basis sets for main group elements and
LANL2DZ basis sets for metal atoms. For Cl we added polarization
functions. For the model compounds [N{(CF3)C(C6H5)N}2]
M(EtCt CEt) (M ) Au, Ag, Cu) we found minimum structures in
Cs-symmetry as indicated by the frequency analysis. A C2V-
(45) Frisch, M. J.; et al. Gaussian 03, Revision D.02; Gaussian, Inc.:
Wallingford CT, 2004.
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11254 J. AM. CHEM. SOC. VOL. 131, NO. 31, 2009