5582 Inorganic Chemistry, Vol. 48, No. 12, 2009
Kornev et al.
Yield: 2.43 g (92%). Anal. calcd for C12H30N2P2, %: C, 54.53;
H, 11.44; P, 23.43. Found, %: C, 54.45; H, 11.38; P, 23.60. 1H
NMR (C6D6, 300 K) δ (ppm): 3.36 (d, 2H, NH, 2JH,P = 8.3 Hz),
1.52-1.78 (m, 4H, CH), 0.9-1.30 (m, 24H, CH3). 31P{1H}
65.74; H, 7.36; Co, 8.96. Found, %: C, 65.78; H, 7.43; Co, 8.92.
IR (nujol), ν~/cm-1: 1590s, 1290m, 1230s, 1164m, 1075m, 1021m,
993w, 973m, 879m, 857s, 765m, 754s, 730m, 693s, 669m, 655m,
620m, 573m, 538m, 512m, 501m, 474m. UV/vis spectrum
(Et2O): λmax 420, 538 nm.
NMR (C6D6, 300 K), δ (ppm): 73.6. IR (nujol), ν~/cm-1
:
[CpNi{(NPh-NPh-PiPr2)-κ2N,P}] (8). A mixture of
[Cp2Ni] (0.19 g, 1.0 mmol) and 1,2-diphenyl-1-(diisopropylpho-
sphino)hydrazine (1) (0.30 g, 1.0 mmol) in 15 mL of toluene was
heated at 90 ꢀC for 48 h. The green color of the solution slowly
turned violet. Toluene was distilled off; the residue was heated in
a vacuum at 50 ꢀC to sublime off the unconsumed [Cp2Ni]. The
dark violet product was purified by crystallization from THF to
give 8 as fine needles. Yield: 0.27 g (63%). Anal. calcd for
C23H29N2 PNi, %: C, 65.28; H, 6.91; Ni, 13.87. Found, %: C,
3220s, 1630m, br, 1304m, 1260m, 1230s, 1186w, 1152m,
1100m, 1020s, 963w, 924m, 876s, 810s, 655s, 608m, 500m.
iPr2P-NMe-NH-PiPr2 (3). A solution of chlorodiiso-
propylphosphine (3.05 g, 20 mmol) in THF was added dropwise
to a stirred solution of methylhydrazine (1.38 g, 30 mmol) in the
same solvent at 20 ꢀC. The mixture was stirred for 3 h and then
filtered. The solvent was removed in a vacuum, and pentane was
added. Methylhydrazine hydrochloride was filtered off. Pentane
was removed in a vacuum, and the residue was distilled at
reduced pressure. Bp 100 ꢀC/0.2 mm Hg. Yield: 2.5 g (90%).
Anal. calcd for C13H32N2P2, %: C, 56.09; H, 11.59; P, 22.25.
Found, %: C, 55.95; H, 11.52; P, 22.30. 1H NMR (C6D6,
300 K), δ (ppm): 3.37 (s, 1H, NH), 2.78 (s, 3H, MeN), 1,64-
1.83 (m, 2H, CH(CH3)2), 1.40-1.56 (m, 2H, CH(CH3)2), 0.70-
1.35 (m, 24H, CH3). 31P{1H} NMR (C6D6, 300 K), δ (ppm): 88.9
(s) and 66.5 (s). IR (KBr), ν~/cm-1: 3265m (NH), 1188s, 1154m,
1098w, 1017m, 924w, 878m, 809m, 690s, 651m, 603m, 515m.
1
65.31; H, 6.94; Ni, 13.83. H NMR (C6D6, 300 K): δ 6.3-7.5
(m, 10H, Ph), 5.3 (5H, s, Cp), 2.0-2.5 (m, 2H, CH), 0.7-1.7
(m, 12H, CH3). 31P{1H} NMR (C6D6, 300 K): δ 67.0 ppm. IR
(nujol), ν~/cm-1: 1592s, 1288s, 1230m, 1160m, 1074m, 1023m,
960m, 885m, 822m, 780m, 752s, 731w, 693s, 615w, 568w, 512m.
UV/vis spectrum (Et2O): λmax 410, 542 nm.
[FeCl2{(PiPr2-NMe-NH-PiPr2)-κ2P,P0}] (9). 1-Methyl-
1,2-bis(diisopropylphosphino)hydrazine (2.78 g, 10.0 mmol)
was mixed with solid anhydrous FeCl2 (1.27 g, 10.0 mmol).
A weak exothermic reaction took place. Toluene (15 mL) was
added; the mixture was heated at 80 ꢀC for 20 min. The hot
toluene solution was filtered. Slow cooling and keeping the
solution at room temperature gave yellow crystals of 9. Yield:
3.72 g (92%). Anal. calcd for C13H32N2P2FeCl2, %: C, 38.54; H,
7.96; Cl, 17.50; Fe, 13.79. Found, %: C, 38.48; H, 8.03; Cl, 17.46;
Fe, 13.70. IR (KBr), ν~/cm-1: 3240s, 1292w, 1244s, 1214m,
1138s, 1117m, 1023s, 990s, 933m, 882s, 839m, 699s, 667m,
626s, 575m, 489w, 465w, 446w.
iPr2P-NH-NHMe (4). A solution of chlorodiisopropyl-
phosphine (3.05 g, 20 mmol) in THF was added dropwise to a
stirred solution of methylhydrazine (1.84 g, 40 mmol) in the
same solvent at 20 ꢀC. The mixture was stirred for 1 h and then
filtered. The solvent was removed in a vacuum, and pentane was
added. Additional precipitate of methylhydrazine hydrochlor-
ide was filtered off. Pentane was removed in a vacuum, and the
residue was distilled at reduced pressure. Bp 35 ꢀC (0.2 mm Hg).
Yield: 2.9 g (83%). Anal. calcd for C7H19N2P, %: C, 51.83; H,
11.81; P, 19.09. Found, %: C, 51.79; H, 11.85; P, 19.13. 1H NMR
(C6D6, 300 K): δ 3.05 (d, 1H, PNH, J H,P = 12 Hz), 2.60 (s, 1H,
HNCH3), 2.32 (s, 3H, NCH3 ), 1.60-1.80 (m, 2H, CH(CH3)2),
0.90-1.20 (m, 12H, CH(CH3)2). 31P{1H} NMR (C6D6, 300 K),
δ (ppm): 65.9 (s). IR (KBr), ν~/cm-1: 3267m (NH), 1380m,
1261m, 1231w, 1182m, 1098m, 1019m, 960w, 878s, 807s, 657s,
607m, 517w.
[FeBr2{(PiPr2-NMe-NH-PiPr2)-κ2P,P0}] (10). Com-
plex 10 was prepared and isolated similarly to 9 by reaction
of 3 with iron(II) bromide. Yield: 0.66 g (81%). Anal. calcd
for C13H32N2P2FeBr2, %: C, 31.61; H, 6.53; Br, 32.35; Fe,
11.31. Found, %: C, 31.57; H, 6.58; Br, 32.30; Fe, 11.26. IR
(nujol), ν~/cm-1: 3250m, 2727w, 1250m, 1215m, 1118s br,
1030m, 993m, 935w, 903w, 882s, 832m, 895s, 670s, 610m,
560m, 472w.
[Co{(PiPr2-NMe-NH-PiPr2)-κ2P,P0}2( μ-Cl)3][CoCl3-
(THF)] (11). A solution of 1-methyl-1,2-bis(diisopropylpho-
sphino)hydrazine (3) (0.55 g, 2.0 mmol) in THF (5 mL) was
added to a solution of CoCl2 (0.39 g, 3.0 mmol) in the same
solvent (25 mL). The mixture turned dark violet-green. Soon,
the formation of dark violet crystals was observed. The solution
was concentrated to 5 mL; an additional portion of crystals
formed. The product was filtered off, washed with cold THF,
and dried in vacuum. Yield: 0.90 g (88%). Anal. calcd for
C30H72N4P 4OCo3Cl6, %: C, 35.38; H, 7.13; Cl, 20.89; Co,
17.36. Found, %: C, 35.32; H, 7.18; Cl, 20.83; Co, 17.31. IR
(KBr), ν~/cm-1: 3390m, 3216s (νNH), 1627m (δNH), 1389m,
1254m, 1221m, 1152m, 1104s, 1033s, 932w, 884s, 729s, 674s,
596m, 549w, 513w, 470w.
[Li(DME)3][Li{(NPh-NPh-PiPr2)-κN}2] (5). Com-
pound 5 was prepared by the addition of an equivalent of
n-butyllithium to a toluene solution of 1 followed by crystal-
lization from dimethoxyethane. The yield is close to quantita-
tive. Anal. calcd for C48H78N4P2Li2O6, %: C, 65.29; H, 8.90;
Li, 1.57. Found, %: C, 65.33; H, 8.94; Li, 1.53. 31P{1H} NMR
(DME, 300 K), δ (ppm): 83.0 (s).
[Ni{(NPh-NPh-PiPr2)-κ2N,P}2] (6). An equivalent
of n-BuLi in n-hexane (5.0 mL, 1 M) was added to a solution
of H-NPh-NPh-PiPr2 (1) in THF (1.50 g, 5.0 mmol, 10 mL)
at 0 ꢀC. The resulting mixture was kept at 20 ꢀC for 0.5 h and was
then added to a suspension of [NiBr2(THF)2] (0.91 g, 2.5 mmol)
in 10 mL of THF. Nickel bromide dissolved immediately to give
a deep blue solution. Keeping the mixture overnight at 0 ꢀC gave
a deep blue crystalline precipitate of 6. Yield: 1.50 g (91%).
Anal. calcd for C36H48N4P 2Ni, %: C, 65.77; H, 7.36; Ni, 8.93.
Found, %: C, 65.72; H, 7.40; Ni, 8.89. 1H NMR (d8-THF,
300 K): δ 6.5-7.4 (m, 20H, Ph), 2.0-2.5 (m, 4H, CH(CH3)2),
1.0-1.4 (m, 24H, CH(CH3)2). 31P{1H} NMR (d8-THF, 300 K),
δ 79.0 ppm. IR (nujol), ν~/cm-1: 1590s, 1288m, 1253s, 1225s,
1168m, 1097ww, 1065m, 1029s, 989m, 961s, 890m, 876ww,
8942m, 825m, 752vs, 697s, 669m, 662m, 620m, 546m, 513s.
UV/vis spectrum (THF): λmax 350, 530 nm.
Synthesis of LiNdPiPr2-NMe-PiPr2 (13) and iPr2P-
NMe-PiPr2dNH (14) in Situ. An equivalent of n-butyl-
lithium (1.0 M solution in n-hexane, 2.0 mL) was added to a
solution of 1-methyl-1,2-bis(diisopropylphosphino)hydrazine
(3) (0.56 g, 2.0 mmol) in THF (10 mL). The mixture was kept
for 1 h, and then used in further reactions.
[Co{(NPh-NPh-PiPr2)-κ2N,P}2] (7). A solution of
1,2-diphenyl-1-(diisopropylphosphino)hydrazine (1) in Et2O
(3.00 g, 10.0 mmol) was added to a solution of [Co{N(SiMe3)2}2]
(1.90 g, 5.0 mmol) in the same solvent. The resulting mixture
turned dark violet. Dark violet crystals formed rapidly. The
mixture was kept at 20 ꢀC for 2 h and then filtered. Crystals of 7
were washed with cold diethyl ether and dried in a vacuum.
An aliquot of the mixture was hydrolyzed by an equivalent
amount of a 1 M solution of H2O in THF. The resulting solution
of 14 was studied by 31P{1H} NMR δ (ppm): 68.0 (d, JP,P
41 Hz), 59.9 (d, JP,P = 41 Hz).
=
[CoCl2{(HNdPiPr2-NMe-PiPr2)-κ2N,P}] (15).
A
THF solution of 14, prepared from 0.56 g (2.0 mmol) of 3 as
described above, was added to a solution of CoCl2 (0.26 g,
2.0 mmol) in 15 mL of THF. The mixture was kept for 12 h at
Yield: 2.80 g (85%). Anal. calcd for C36H48N4P Co, %: C,
2