5366 Organometallics, Vol. 15, No. 25, 1996
Gross and Girolami
ESP 300 spectrometer. Melting points were measured on a
Thomas-Hoover Unimelt apparatus in sealed capillaries under
argon.
(P en ta m eth ylcyclop en ta d ien yl)br om o[1,2-bis(d im eth -
ylp h osp h in o)eth a n e]osm iu m (II), (C5Me5)Os(d m p e)Br (6).
To a slurry of (C5Me5)2Os2Br4 (0.30 g, 0.31 mmol) in ethanol
(30 mL) was added 1,5-cyclooctadiene (0.43 mL, 3.5 mmol).
The solution was refluxed for 2 h, and the solvent was then
removed under vacuum. To the remaining solid was added
heptane (30 mL) followed by 1,2-bis(dimethylphosphino)ethane
(0.75 mL, 4.5 mmol). The solution was refluxed for 2 h and
filtered hot, and the filtrate was cooled to -20 °C to afford
thin orange plates. Yield: 0.22 g (64%). MS (FD): m/z 556
[M+]. 31P{1H} NMR (25 °C, C7D8): δ 8.4 (s). IR (cm-1): 2730
(w), 2709 (w), 1414 (s), 1287 (s), 1274 (s), 1237 (w), 1154 (w),
1086 (m), 1070 (m), 1027 (s), 932 (s), 924 (s), 904 (s), 893 (s),
835 (s), 800 (m), 777 (m), 721 (s), 699 (s), 650 (s), 610 (m), 584
(w), 461 (m), 444 (w).
(P en t a m et h ylcyclop en t a d ien yl)b r om o[b is(d ip h en yl-
ph osph in o)m eth an e]osm iu m (II), (C5Me5)Os(dppm )Br (7).
To a mixture of (C5Me5)Os(cod)Br (0.49 g, 0.95 mmol) and bis-
(diphenylphosphino)methane (0.37g, 0.96 mmol) was added
heptane (20 mL). The solution was refluxed for 22 h resulting
in the formation of an orange microcrystalline solid. The solid
was isolated by filtration. Yield: 0.48 g (64%). MS(FD): m/z
790 [M+]. 31P{1H} NMR (25 °C, C7D8): δ -34.4 (s). IR (cm-1):
3069 (m), 3052 (m), 2725 (w), 1954 (w), 1882 (w), 1810 (w),
1798 (w), 1586 (w), 1572 (w), 1483 (m), 1433 (s), 1355 (w), 1305
(w), 1275 (w), 1262 (w), 1184 (w), 1175 (w), 1156 (w), 1097 (s),
1083 (m), 1069 (m), 1027 (m), 1000 (w), 988 (w), 966 (w), 849
(w), 838 (w), 801 (w, br), 763 (w), 748 (w), 741 (m), 735 (s),
721 (s), 697 (s), 689 (sh), 665 (w), 652 (w), 616 (w), 542 (s),
534 (w), 512 (s), 482 (m), 473 (w), 450 (m), 427 (m), 420 (w),
410 (w), 406 (w).
(P en ta m eth ylcyclop en ta d ien yl)h yd r id o(1,5-cycloocta -
d ien e)osm iu m (II), (C5Me5)Os(cod )H (8). To a mixture of
(C5Me5)Os(cod)Br (0.50 g, 0.98 mmol) and NaBH4 (0.11 g, 3.0
mmol) was added ethanol (40 mL). The resulting solution was
refluxed for 45 min, the solvent was removed under vacuum,
and the residue extracted with diethyl ether (3 × 30 mL). The
extracts were filtered, and the filtrates were combined, con-
centrated to ca. 5 mL, and cooled to -20 °C to afford off-white
crystals. Additional crops of crystals were obtained by further
concentrating and cooling the supernatant. Yield: 0.28 g
(65%). MS (FD): m/z 434 [M+]. IR (cm-1): 2214 (m), 1466
(s), 1410 (w), 1381 (s), 1317 (s), 1236 (m), 1200 (w), 1150 (m),
1072 (w), 1029 (m), 1008 (w), 979 (w), 902 (w), 869 (w), 827
(s), 809 (m), 783 (m), 667 (m), 622 (w), 544 (w), 524 (w), 507
(w), 492 (w).
(P en ta m eth ylcyclop en ta d ien yl)h yd r id obis(tr ip h en yl-
p h osp h in e)osm iu m (II), (C5Me5)Os(P P h 3)2H (9). To a mix-
ture of (C5Me5)Os(PPh3)2Br (0.90 g, 0.97 mmol) and NaBH4
(0.13 g, 3.3 mmol) was added ethanol (70 mL). The solution
was refluxed for 1 h and then was filtered while still hot.
Cooling the solution to room temperature yielded yellow
microcrystals, which were collected by filtration. Yield: 0.54
g (64%). MS (FD): m/z 852 [M+]. 31P{1H} NMR (25 °C, CD2-
Cl2): δ 23.6 (s). IR (cm-1): 3071 (m), 3055 (s), 2720 (w), 2648
(w), 1978 (s), 1946 (w), 1586 (w), 1573 (w), 1478 (s), 1433 (s),
1310 (w), 1264 (w), 1180 (w), 1162 (w), 1154 (w), 1089 (s), 1082
(s), 1032 (m), 1001 (w), 972 (w), 910 (w), 846 (w), 801 (w), 752
(m), 748 (m), 744 (s), 737 (m), 714 (m), 697 (s), 691 (s), 680 (s),
664 (m), 620 (w), 546 (s), 525 (s), 511 (s), 504 (s), 491 (m), 469
(m), 453 (m).
(P en ta m eth ylcyclop en ta d ien yl)br om o(1,5-cycloocta -
d ien e)osm iu m (II), (C5Me5)Os(cod )Br (1). To a slurry of
(C5Me5)2Os2Br4 (0.62 g, 0.64 mmol) in ethanol (40 mL) was
added 1,5-cyclooctadiene (0.82 mL, 6.7 mmol). The solution
was refluxed for 90 min, and the solution color changed to a
clear orange and an off-white precipitate formed. The solvent
was removed under vacuum, the residue was extracted with
diethyl ether (4 × 30 mL), and the extracts were filtered. The
filtrates were combined, concentrated to ca. 50 mL, and cooled
to -20 °C to afford orange crystals. Additional crops of crystals
were obtained by further concentrating and cooling the
supernatant. Yield: 0.48 g (74%). MS (FD): m/z 514 [M+].
IR (cm-1): 1514 (w), 1321 (m), 1295 (w), 1261 (w), 1239 (w),
1207 (w), 1152 (m), 1072 (w), 1026 (m), 1010 (m), 993 (m), 887
(w), 842 (m), 813 (w), 791 (w), 603 (w), 526 (w), 487 (w).
(P en t a m et h ylcyclop en t a d ien yl)b r om ob is(t r ip h en yl-
p h osp h in e)osm iu m (II), (C5Me5)Os(P P h 3)2Br (2). To a
mixture of (C5Me5)2Os2Br4 (0.62 g, 0.64 mmol) and PPh3 (1.2
g, 4.6 mmol) was added ethanol (50 mL). The resulting
solution was refluxed for 9 h; a red-orange precipitate formed
initially, but over the course of the reaction this material
disappeared and was replaced by an orange-yellow, micro-
crystalline precipitate. The orange-yellow microcrystals were
isolated by filtration. Yield: 0.67 g (56%). MS (FD): m/z 668
[(M - PPh3)+]. 31P{1H} NMR (25 °C, CD2Cl2): δ -2.9 (s). IR
(cm-1): 3051 (m), 2723 (w), 1963 (w), 1902 (w), 1826 (w), 1781
(w), 1585 (w), 1573 (w), 1478 (s), 1433 (s), 1310 (w), 1263 (m),
1185 (w), 1160 (w), 1087 (s), 1080 (s), 1028 (m), 1000 (w), 855
(w), 743 (s), 736 (m), 731 (m), 698 (s), 666 (w), 620 (w), 538 (s),
522 (s), 513 (s), 501 (s), 491 (m), 470 (m).
(P en t a m et h ylcyclop en t a d ien yl)b r om ob is(t r im et h yl-
p h osp h in e)osm iu m (II), (C5Me5)Os(P Me3)2Br (3). To a
solution of (C5Me5)2Os2Br4 (0.88 g, 0.91 mmol) in dichlo-
romethane (70 mL) was added PMe3 (0.80 mL, 7.9 mmol). The
resulting mixture was stirred at room temperature for 2 h,
and the solution color changed from brown to clear yellow. The
solvent was removed under vacuum, the residue was extracted
with pentane (4 × 40 mL), and the extracts were filtered. The
filtrates were combined, concentrated to ca. 50 mL, and cooled
to -20 °C to afford orange crystals. Additional crops of crystals
were obtained by further concentrating and cooling the
supernatant. Yield: 0.67 g (66%). MS (FD): m/z 558 [M+].
31P{1H} NMR (25 °C, CD2Cl2): δ -45.6 (s). IR (cm-1): 1418
(m), 1295 (m), 1280 (m), 1068 (w), 1027 (m), 939 (s), 849 (m),
803 (w), 717 (m), 676 (m), 667 (m), 607 (w).
(P en tam eth ylcyclopen tadien yl)br om obis(tr ieth ylph os-
p h in e)osm iu m (II), (C5Me5)Os(P Et3)2Br (4). To a slurry of
(C5Me5)Os(cod)Br (0.37 g, 0.71 mmol) in heptane (30 mL) was
added triethylphosphine (1.2 mL, 8.1 mmol). The solution was
refluxed for 4 days and then was filtered while still hot. The
filtrate was cooled to -20 °C to afford orange-red crystals.
Yield: 0.20 g (44%). MS (FD): m/z 642 [M+]. 31P{1H} NMR
(25 °C, CD2Cl2): δ -23.8 (s). IR (cm-1): 2726 (w), 1547 (w),
1425 (m), 1357 (m), 1297 (w), 1257 (m), 1190 (w), 1181 (w),
1169 (w), 1154 (w), 1097 (w), 1066 (m), 1027 (s), 931 (w), 872
(w), 854 (w), 807 (w), 757 (s), 730 (m), 702 (m), 677 (m), 636
(w), 609 (m), 556 (w), 532 (w), 517 (w), 453 (w).
(P en t a m et h ylcyclop en t a d ien yl)b r om o[b is(d im et h yl-
ph osph in o)m eth an e]osm iu m (II), (C5Me5)Os(dm pm )Br (5).
To a slurry of (C5Me5)Os(cod)Br (0.25 g, 0.48 mmol) in heptane
(40 mL) was added bis(dimethylphosphino)methane (0.38 mL,
2.4 mmol). The solution was refluxed for 2 h and then was
filtered while still hot. The filtrate was cooled to -20 °C to
afford thin orange plates. Yield: 0.18 g (69%). MS (FD): m/z
542 [M+]. 31P{1H} NMR (25 °C, C7D8): δ -69.5 (s). IR (cm-1):
1426 (w), 1410 (m), 1289 (w), 1285 (w), 1276 (m), 1077 (m),
1031 (w), 947 (m), 929 (s), 855 (m), 842 (m), 733 (m), 705 (m),
658 (w), 611 (w), 584 (w).
(P en ta m eth ylcyclop en ta d ien yl)h yd r id o[bis(d ip h en yl-
ph osph in o)m eth an e]osm iu m (II), (C5Me5)Os(dppm )H (10).
To (C5Me5)Os(dppm)Br (0.41 g, 0.52 mmol) and NaBH4 (0.05
g, 1.3 mmol) was added ethanol (40 mL), and the solution was
refluxed for 4 days. The solution was filtered hot, and the
filtrate was cooled to -20 °C to afford yellow microcrystals.
Yield: 0.22 g (60%). MS (FD): m/z 712 [M+]. 31P{1H} NMR
(25 °C, C7D8): δ -34.1 (s). IR (cm-1): 3067 (w), 3054 (w), 3042
(w), 3010 (w), 2713 (w), 2060 (m), 2040 (w), 2018 (w), 1954
(w), 1879 (w), 1812 (w), 1585 (w), 1571 (w), 1480 (m), 1433 (s),
1403 (w), 1325 (w), 1303 (w), 1275 (w), 1174 (w), 1156 (w),
Gross, Christopher L.
