Osmium-Hexahydride Complex
δ 11.47 (dd, J H ) 10 Hz, J H
Organometallics, Vol. 23, No. 15, 2004 3637
C ) 8 Hz, 1H, OsCHD); high-
-H
obtained. Yield: 81.6 mg (67%). 2H NMR (46.03 MHz, CH2Cl2,
253 K): δ 4.2 (s, 0.24D, CDpy), 3.4 and 3.1 (both s, 0.25D,
CDH), -4.5 (br, 0.09D, OsD), -13.3 (t(1:1:1)dd, J H-D ) 4.7 Hz,
J P-D ) J P′-D ≈ 2 Hz, 0.17D, Os(η2-HD)).
-H
D
E
D
field region (OsH3 unit), δ -5.05 and -11.33 (both d, J H
-H
A
B
) 25 Hz, 1H, HA and HB), -12.20 (d, J H
) 8 Hz, 1H, HC).
-H
C
D
31P{1H} NMR (121.42 MHz, C7D8, 293 K): δ 26.8 (s). 13C{1H}
NMR (75.42 MHz, C7D8, 293 K): δ 203.9 (t, J P-C ) 6.4 Hz,
OsCH), 169.6 (s, Cipso), 158.6 (s, CH), 132.4, 127.2, 119.3, and
115.5 (all s, py), 27.7 (vt, N ) 24.4 Hz, PCH), 20.1 and 19.8
(both s, PCHCH3). MS (FAB+): m/z 613 (M+ - 2H). T1(min) (ms,
OsH3, 300 MHz, C7D8, 203 K): 108 ( 3 (-5.05 ppm, 1H), 102
( 2 (-11.33 ppm, 1H), 114 ( 1 (-12.20 ppm, 1H).
Ca ta lytic Hyd r ogen a tion of 2-Vin ylp yr id in e. A solution
of 3 (114.0 mg, 0.162 mmol) and 2-vinylpyridine (1.75 mL, 16.2
mmol) in 15 mL of dichloromethane was stirred under a
hydrogen atmosphere. The reaction was monitored by GC-
MS. The products were identified by comparison of their mass
spectra with those of the G1045B Spectral Library (Willey 7N,
Agilent Technologies, 2000). The yields of formation of 2-eth-
ylpyridine after 1, 4, and 50 h were 10%, 20%, and 39%,
respectively. After 50 h, the reaction was stopped and the
resulting solution was concentrated in vacuo. The 1H and
31P{1H} NMR spectra of the residue obtained, in CD2Cl2,
revealed the formation of 4.
The addition of 0.05 equiv of OsH6(PiPr3)2 to an NMR tube
containing 2 in toluene-d8 or benzene-d6 gives, after 10 h, the
complex 2 partially deuterated in the pyridine ring. H NMR
1
(300 MHz, C6D6 or C7D8, 293 K, pyridine ring): δ 9.57 (s, 1H,
2
HR py), 7.06 (s, 1H, Hâ′ py). H NMR (300 MHz, C6H6, 293 K):
δ 6.98 and 6.20 (both s, 1D, Dγ and Dâ py). 13C{1H} NMR (75.42
MHz, C7D8, 293 K, Cγ and Câ of the pyridine ring, no changes
in the other signals): δ 115.5 (t(1:1:1), J C-D ) 24.6 Hz), 132.4
(t(1:1:1), J C-D ) 24.3 Hz).
P r ep a r a tion of Os(NC5H4-o-CHdCH)Cl(η2-H2)(P iP r 3)2
(4). A yellow solution of 3 (203.1 mg, 0.288 mmol) in 15 mL of
dichloromethane was heated under reflux for 16 h. The yellow
solution was filtered through Celite and dried in vacuo.
Pentane was added to afford a yellow oil, which was washed
with further portions of pentane at 223 K and dried in vacuo.
Yield: 63.2 mg (34%). IR (KBr, cm-1): ν(OsH) 2174 (m); ν(Cd
Rea ction of 2 w ith HBF 4‚OEt2 a n d H2. A yellow solution
of 2 (20.0 mg, 0. 032 mmol) in CD2Cl2 in an NMR tube was
treated with 1.0 equiv of HBF4‚OEt2 (4 µL, 0.032 mmol), and
the tube was sealed under hydrogen atmosphere. After 4 h,
the 1H and 31P{1H} NMR spectra of the resulting solution
revealed the formation of complex 1 and [HNC5H5-o-CH2CH3]-
BF4. Data for [HNC5H5-o-CH2CH3]BF4: 1H NMR (300 MHz,
CD2Cl2, 293 K): δ 12.99 (br, 1H, NH), 8.66 (d, J H-H ) 7.7 Hz,
1H, py), 8.51 (vt, J H-H ) 7.7 Hz, 1H, py), 7.89 (d, J H-H ) 7.7
Hz, 1H, py), 7.87 (vt, J H-H ) 7.7 Hz, 1H, py), 3.14 (quartet,
1
C) 1602 (s). H NMR (300 MHz, C6D6, 293 K, plus COSY): δ
10.57 (d, J H-H ) 6.7 Hz, 1H, HR py), 10.06 (dt, J H-H ) 7.3 Hz,
J H-H ) 4.6 Hz, 1H, OsCH), 7.32 (d, J H-H ) 7.3 Hz, 1H, CH),
6.98 (d, J H-H ) 6.7 Hz, 1H, Hâ′ py), 6.92 and 6.48 (both vt,
J H-H ) 6.7 Hz, 1H, Hâ and Hγ py), 2.30 (m, 6H, PCH), 1.08
and 0.96 (both dvt, N ) 12.6 Hz, J H-H ) 6.9 Hz, 18H, PCCH3),
-7.71 (td, J H-P ) 12.5 Hz, J H-H ) 4.6 Hz, 2H, OsH). 31P{1H}
NMR (121.42 MHz, C6D6, 293 K): δ 9.02 (s). 13C{1H} NMR
(75.42 MHz, C6D6, 293 K, plus APT): δ 180.6 (t, J P-C ) 6.1
Hz, OsCH), 167.8 (s, Cipso), 151.1 (s, dCH), 134.6, 125.1, 118.5
and 114.3 (all s, py), 25.6 (vt, N ) 23.7 Hz, PCH), 19.5 and
19.4 (both s, PCCH3). MS (FAB+): m/z 651 (M+ - 2H). T1(min)
(ms, OsH2, 300 MHz, CD2Cl2, 193 K): 39 ( 1 (-7.75 ppm, 2H).
J H-H ) 7.5 Hz, 2H, CH2), 1.43 (t, J H-H ) 7.5 Hz, 3H, CH3). 19
NMR (282.33 MHz, CD2Cl2, 293 K): δ -151.0 (br).
F
P r ep a r a t ion of [OsH (η2-H 2)(η2-CH2dCH -o-C5H 4N)(P i-
P r 3)2]BF 4 (3). A yellow solution of 2 (131.4 mg, 0.213 mmol)
in 30 mL of diethyl ether was treated with 1 equiv of HBF4‚
OEt2 (29 µL, 0.213 mmol) and stirred for 40 min at room
temperature. During the course of the reaction a white solid
formed. The solvent was removed, and the solid was washed
with further portions of diethyl ether and dried in vacuo.
Yield: 137.6 mg (92%). Anal. Calcd for C25H52BF4NOsP2: C
42.55, H 7.43, N 1.98. Found: C 42.37, H 7.85, N 1.97. IR (KBr,
cm-1): ν(OsH) 2152 (s), 2098 (m); ν(CdC) 1603 (s); ν(BF4) 1050
Os(NC5H4-o-CHdCH)Cl(η2-HD)(PiPr3)2 was obtained from
4 stirred in CD3OD for 1 day. 1H NMR (300 MHz, CD3OD,
293 K, high-field region): δ -7.71 (tt(1:1:1) d, J H-P ) 12.5 Hz,
J H-D ) 6.3 Hz, J H-H ) 4.6 Hz).
Rea ction of OsH6(P iP r 3)2 w ith N-Meth ylen e-2-p yr id in -
a m in e. A colorless solution of OsH6(PiPr3)2 (207.0 mg, 0.401
mmol) in 15 mL of toluene was treated with 1.4 equiv of
N-methylene-2-pyridinamine (59.4 mg, 0.560 mmol) and heated
under reflux for 5 h. The resulting orange solution was filtered
(br). 1H NMR (300 MHz, CD2Cl2, 293 K): δ 8.18 (d, J H-H
)
7.0 Hz, 1H, HR py), 7.74 and 7.22 (both vt, J H-H ) 7.0 Hz, 1H,
Hâ and Hγ py), 7.04 (d, J H-H ) 7.0 Hz, 1H, Hâ′ py), 4.23 (br,
1H, CH2), 3.40 (br, 1H, CH2), 3.16 (d, J H-H ) 7.8 Hz, 1H, CH),
2.42 and 2.21 (both m, 3H, PCH), 1.16 (dvt, N ) 12.6 Hz, J H-H
) 6.9 Hz, 27H, PCHCH3), 0.92 (br, 9H, PCCH3), -4.53 (br,
1
through Celite and dried in vacuo. The H and 31P{1H} NMR
1
spectra of the residue, in benzene-d6, indicated the formation
of two products: 5 and 6 in a 3:1 ratio. Methanol was added
to afford complex 5 as a yellow solid, which was washed with
further portions of methanol at 223 K and dried in vacuo.
Complex 6 was the major component in the supernatant
solution, but it could not be isolated purely.
1H, OsH), -13.29 (br, 2H, OsH). H NMR (300 MHz, CD2Cl2,
253 K): δ 8.16 (d, J H-H ) 7.0 Hz, 1H, HR py), 7.72 and 7.21
(both vt, J H-H ) 7.0 Hz, 1H, Hâ and Hγ py), 7.03 (d, J H-H
)
7.0 Hz, 1H, Hâ′ py), 4.16 (ddd, J H-P ) 8.1 Hz, J H-H ) 8.1 Hz,
J H-H ) 7.6 Hz, 1H, CHpy), 3.36 (dd, J H-P ) 13.2 Hz, J H-H
)
8.1 Hz, 1H, CH cis to py), 3.13 (d, J H-H ) 7.6 Hz, 1H, CH trans
to py), 2.40 and 2.18 (both m, 3H, PCH), 1.13 (dvt, N ) 12.6
Hz, J H-H ) 6.9 Hz, 27H, PCCH3), 1.13 (dvt, N ) 12.6 Hz, J H-H
Da ta for OsH3(NC5H4-o-NCH3)(P iP r 3)2 (5). Yield: 129.3
mg (52%). Anal. Calcd for C24H52N2OsP2: C 46.43, H 8.44, N
4.51. Found: C 46.56, H 8.24, N 4.92. IR (KBr, cm-1): ν(OsH)
2134 (s), 2116 (s). 1H NMR (300 MHz, C7D8, 293 K): δ 7.88 (d,
J H-H ) 7.0 Hz, 1H, HR py), 6.88 and 5.87 (both vt, J H-H ) 7.0
Hz, 1H, Hâ and Hγ py), 5.55 (d, J H-H ) 7.0 Hz, 1H, Hâ′ py),
3.05 (s, 3H, CH3), 1.93 (m, 6H, PCH), 1.14 and 1.08 (both dvt,
N ) 12.5 Hz, J H-H ) 6.3 Hz, 18H, PCHCH3), -11.88 (br, 3H,
) 6.9 Hz, 9H, PCCH3), -4.55 (dd, J H-P ) 23.7 Hz, J H-P′
)
16.8 Hz, 1H, OsH), -13.30 (dd, J H-P ) J H-P′ ) 11.4 Hz, 2H,
OsH2). 31P{1H} NMR (121.42 MHz, CD2Cl2, 293 K): AB spin
system, δ 20.1, ∆ν ) 189 Hz, J AB ) 157 Hz. 19F NMR (282.33
MHz, CD2Cl2, 293 K): δ -155.4 (br). 13C{1H} NMR (75.42
MHz, CD2Cl2, 233 K, plus APT): δ 165.6 (s, Cipso), 149.1, 136.7,
124.5, and 122.9 (all s, py), 46.7 (s, CH2), 42.8 (s, CH), 27.9 (d,
J C-P ) 25.5 Hz, PCH), 27.0 (d, J C-P ) 26.3 Hz, PCH), 19.7,
19.6, 19.3, and 18.5 (all s, PCHCH3). MS (FAB+): m/z 610 (M+
- 10H). T1(min) (ms, OsH3, 300 MHz, CD2Cl2, 193 K): 129 ( 6
(-4.58 ppm, 1H), 48 ( 2 (-13.35 ppm, 2H).
OsH). H{31P} NMR (300 MHz, C7D8, 183 K, in the high-field
1
region): δ -10.97 (d, J H-H ) 11.6, 1H), -11.65 (d, J H-H ) 24.7,
1H), -12.24 (dd, J H-H ) 24.7, J H-H ) 11.6, 1H). 31P{1H} NMR
(121.42 MHz, C7D8, 293 K): δ 26.4 (s). 13C{1H} NMR (75.42
MHz, C7D8, 293 K): δ 167.5 (s, Cipso), 149.2, 133.1, 102.9, and
102.1 (all s, py), 36.0 (s, CH3), 27.3 (vt, N ) 23.0 Hz, PCH),
P r ep a r a t ion of [OsH (η2-H 2)(η2-CH2dCH -o-C5H 4N)-
(P iP r 3)2]BF 4 P a r tia lly Deu ter a ted . This complex was pre-
pared as described for 3 starting from 2 (106.1 mg, 0.172 mmol)
and DBF4‚D2O (33 µL, 0.173 mmol). A white solid was
20.3 and 20.1 (both s, PCHCH3). MS (FAB+): m/z 619 (M+
-
3H). T1(min) (ms, OsH3, 300 MHz, C7D8, 208 K): 109 ( 2 (-10.97
ppm, 1H), 94 ( 1 (-11.65 ppm, 1H), 87 ( 1 (-12.24 ppm, 1H).