Article
Inorganic Chemistry, Vol. 48, No. 22, 2009 10791
125.77 (OC6H4NO2 3,5-C), 121.04 (sl br due to unresolved JPC
C5H4 H-2 and H-5), 4.71 (br m, 4H, C5H4 H-3 and H-4), 4.35 (s,
10H, C5H5), 4.00 (d, 14 Hz, 2H, CHH0), 3.24 (d, 14 Hz, 2H,
CHH0). 13C{1H} NMR (CD2Cl2): δ 188.82, 186.45 (CO),
140.82, 135.79, 133.49, 130.00, 128.70, 127.75 (aromatic),
106.81 (COCHCO), 75.37 (Fc ipso), 74.62, 74.31, 71.58
(C5H5), 70.99, 69.75, 45.26 (CH2). IR (nujol mull): 2923 (s),
2724 (w), 1459 (s), 1377 (s), 1295 (w), 1213 (w), 1152 (w), 1123
(w), 1104 (w), 1028 (w), 1002 (w), 973 (w), 844 (w), 822 (w) 787
(w), 757 (w), 721 (w), 681 (w). UV-vis: 325 nm (16100 M-1
cm-1), 639 nm (3370 M-1 cm-1). Anal. Calcd for
C42H32Cl2Fe2O4Ti: C, 62.49%; H, 4.00%. Found: C, 60.18%;
H, 4.76%.
,
OC6H4NO2 2,6-C), 106.79 (COCHCO), 75.78, 75.40, 74.07 (Fc
ipso), 71.88 (C5H5), 70.81, 70.62, 70.04, 44.70 (CH2). 31P{1H}
NMR (CDCl3): δ -21.06. IR (nujol mull): 2726 (w), 2678 (w),
1613 (w), 1590 (w), 1518 (s), 1345 (s), 1297 (m), 1271 (m), 1214
(m), 1161 (w), 1109 (w), 1066 (w), 1007 (w), 974 (w), 918 (m), 854
(w), 818 (w), 750 (w), 722 (w). UV-vis: 276 nm (54800 M-1
cm-1), 661 nm (5360 M-1 cm-1). Anal. Calcd for C67H55Fe2-
N4O20P2Ti: C, 55.20%; H, 3.80%. Found: C 55.30%; H, 4.05%.
(Fc2Bob)Ti(OiPr)[O2P(OC6H4NO2)2]. In the drybox, 0.0808
g of (Fc2Bob)Ti(OiPr)2 (9.46 ꢀ 10-5 mol) and 0.0352 g of bis(4-
nitrophenyl) phosphate (1.04 ꢀ 10-4 mol, 1.1 equiv) were
weighed into a 20 mL glass vial and dissolved in about 4 mL
of benzene. The color changed from red-orange to reddish
purple immediately. Pentane (∼4 mL) was added by vapor
diffusion overnight. The dark red-purple filtrate was pipetted
off, leaving a reddish purple precipitate and some purple-
colored film in the bottom of the vial. The solids were slurried
with about 3 mL of hexanes, filtered, and dried to give 0.0872 g
(81%) of the monoalkoxide product. 1H NMR (CDCl3): δ 8.04
(d, 9 Hz, 2H, POAr 3,5-H), 8.02 (d, 9 Hz, 2H, POAr0 3,5-H), 7.42
(m, 2H, biphenyl), 7.38 (d, 9 Hz, 2H, POAr 2,6-H), 7.34 (d, 9 Hz,
2H, POAr0 2,6-H), 7.28 (m, 3H, biphenyl), 7.21 (m, 2H,
biphenyl), 7.00 (d, 8 Hz, 1H, biphenyl), 5.02 (s, 1H, COCHCO),
5.01 (sept, 6 Hz, 1H, OCH(CH3)2), 5.01 (s, 1H, COCHCO), 4.59
(m, 1H, C5H4 H-2), 4.58 (sl br, 1H, C5H4 H-20), 4.53 (m, 2H,
C5H4), 4.49 (m, 2H, C5H4), 4.43 (sl br, 1H, C5H4 H-5), 4.37 (m,
1H, C5H4 H-50), 4.18 (s, 5H, C5H5), 4.17 (s, 5H, C5H05), 3.97 (d,
14 Hz, 1H, CHH0), 3.85 (d, 14 Hz, 1H, CHH0), 3.22 (d, 14 Hz,
1H, CHH0), 2.91 (d, 14 Hz, 1H, CHH0), 1.38 (d, 6 Hz, 3H,
OCH(CH3)(CH03)), 1.37 (d, 6 Hz, 3H, OCH(CH3)(CH03). 13C-
{1H} NMR (CDCl3): δ 190.36, 188.37, 186.47, 184.87 (CO),
157.26, 157.21 (POC), 143.88, 143.82 (CNO2), 140.70, 140.58,
136.20, 135.53, 133.44, 133.31, 130.07, 129.62, 128.46, 128.31,
127.29, 127.19 (biphenyl), 125.55 (POAr 3,5-C), 125.53 (POAr0
3,5-C), 120.94 (d, JPC = 6 Hz, POAr 2,6-C), 120.70 (d, JPC = 6
Hz, POAr0 2,6-C), 103.99, 102.90 (COCHCO), 83.90
(TiOCH[CH3]2), 76.24, 73.40, 73.02, 72.48, 72.44, 70.86
(C5H5), 70.62 (C05H5), 70.47, 70.08, 69.81, 69.52, 68.34
(C5H4), 46.01, 45.27 (CH2), 24.80, 24.78 (TiOCH[CH3][C0H3]).
IR (nujol mull): 2724 (w), 1612 (w), 1589 (m), 1347 (s), 1288 (m),
1215 (m), 1155 (w), 1107 (w), 1053 (w), 973 (m), 916 (w), 854 (w),
748 (w), 685 (w). UV-vis: 286 nm (27500 M-1 cm-1), 372 nm
(9500 M-1 cm-1), 540 nm (3600 M-1 cm-1). Anal. Calcd for
C55H47Fe2N2O13PTi: C, 58.22%; H, 4.18%. Found: C, 57.24%;
H, 3.96%.
{(Fc2Bob)Ti(μ-O)}3. (Fc2Bob)Ti(OiPr)2 (0.1025 g, 1.12 ꢀ
10-4 mol) was weighed out in a glass scintillation vial and
dissolved in about 10 mL of THF in the air. Three drops of
deionized water were added, the vial sealed, and the reaction
mixture allowed to stir overnight. The rose-red precipitate was
then vacuum filtered and washed with pentane to yield 0.1024 g
(97%) of the μ-oxo trimer. 1H NMR (CDCl3): δ 7.47 (m, 12H,
biphenyl), 7.32 (d, 7 Hz, 6H, biphenyl), 7.28 (m, 6H, biphenyl),
5.57 (br s, 6H, C5H4 H-2 or -5), 5.03 (s, 6H, COCHCO), 4.29 (s,
30H, C5H5), 4.16 (br s, 6H, C5H4 H-3 or -4), 4.06 (br s, 6H, C5H4
H-3 or -4), 3.92 (d, 14 Hz, 6H, CHH0), 3.90 (br s, 6H, C5H4
H-2 or -5), 3.06 (d, 14 Hz, 6H, CHH0). 13C{1H} NMR (THF-d8):
δ 188.64 (CO), 186.54 (CO), 142.65, 137.48, 134.56, 130.70,
129.06, 127.27, 103.65 (COCHCO), 73.59, 71.77, 71.34 (C5H5),
70.93, 68.02, 47.09 (CH2) [ipso C5H4 not found]. IR (evaporated
film): 3096 (w), 3060 (w), 3016 (w), 2918 (w), 2847 (w), 1550 (s),
1510 (s), 1448 (m), 1399 (m), 1373 (s), 1333 (m), 1315 (m), 1293
(m), 1213 (w), 1151 (w), 1129 (w), 1107 (w), 1054 (w), 1027 (w),
1005 (w), 974 (w), 907 (w), 841 (w), 796 (m), 752 (m), 730 (m).
Anal. Calcd for C120H96Fe6O15Ti3: C, 63.87; H, 4.29. Found: C,
62.23; H, 4.12.
(Fc2Bob)Ti(OC6H4-2-OH)2. Inside the drybox, 0.0826 g of
(Fc2Bob)Ti(OiPr)2 (9.67 ꢀ 10-5 mol) was weighed into a 20 mL
glass vial. To this was added 0.0266 g of catechol (2.42 ꢀ 10-4
mol, 2.5 equiv). The mixture was dissolved in about 4 mL of
benzene, and an immediate color change in the solution was
observed from red-orange to dark blood red. Pentane (∼4 mL)
was added to the solution by vapor diffusion over 9 h, at which
point the red filtrate was decanted and the deep red-brown
needles formed in the vial were washed with pentane. After
drying in vacuo overnight, 0.0696 g of (Fc2Bob)Ti(OC6H4-2-
OH)2 (75%) was isolated. 1H NMR (C6D6): δ 7.71 (s, 2H, OH),
7.37 (dd, 7 Hz, 2 Hz, 2H, catechol H-6), 7.25 (dd, 7 Hz, 2 Hz, 2H,
catechol H-3), 7.00 (m, 6H, biphenyl), 6.92 (m, 2H, biphenyl),
6.81 (m, 4H, catechol H-4,5), 4.99 (s, 2H, COCHCO), 4.56 (sl br,
2H, C5H4 H-2), 4.53 (sl br, 2H, C5H4 H-5), 4.14 (m, 4H, C5H4 H-
3 and H-4), 4.05 (s, 10H, C5H5), 3.59 (d, 14 Hz, 2H, CHH0), 2.93
(d, 14 Hz, 2H, CHH0). 13C{1H} NMR (CD2Cl2): δ 190.06,
187.05 (CO), 156.91, 149.04, 141.09, 136.64, 134.00, 130.02,
128.92, 127.30, 123.28, 120.20, 119.36, 116.43 (aromatic),
103.73 (COCHCO), 77.58 (Fc ipso), 73.40, 71.55, 71.42
(C5H5), 70.56, 70.11, 45.80 (CH2). IR (evapd film): 3399 (w,
νOH), 3082 (w), 3034 (w), 1583 (w), 1514 (s), 1489 (s), 1453 (w),
1415 (w), 1396 (w), 1366 (m), 1294 (m), 1271 (m), 1227 (w) 1203
(w), 1155 (w), 1129 (w), 1109 (w), 1059 (w), 1028 (w), 1001 (w),
978 (w), 894 (w), 819 (w), 797 (w), 745 (w), 679 (w). UV-vis: 297
nm (sh, 24000 M-1 cm-1), 351 nm (20000 M-1 cm-1), 534 nm
(8400 M-1 cm-1). Anal. Calcd for C52H42Fe2O8Ti: C, 65.43%;
H, 4.44%. Found: C 65.16%; H, 4.46%.
(Fc2Bob)Ti[O2P(OC6H4NO2)2]2. Inside the drybox, 0.0774 g
of (Fc2Bob)Ti(OiPr)2 (9.06 ꢀ 10-5 mol) and 0.0615 g of bis(4-
nitrophenyl)phosphate (Aldrich, 1.81 ꢀ 10-4 mol, 2 equiv) were
weighed into a 25 mL round-bottom flask. A stirbar was added,
and the flask was sealed with a needle valve, taken out of the
drybox, and attached to the vacuum line. About 7 mL of CH2Cl2
was vacuum transferred into the flask and, with stirring,
warmed to room temperature, at which point the reaction
mixture began turning from dark red to purple. After about
20 min, the reaction mixture had turned dark green. It was
allowed to stir at room temperature for 6 h. The solvent was
removed, and another 7 mL of fresh CH2Cl2 was distilled into
the reaction flask. After stirring overnight, the solvent was
reduced to a volume of about 3 mL. The solution was then
cooled to -78 °C, and two volumes of heptane were added to the
stirred solution by vacuum transfer. The volume was again
reduced to about 4 mL, effectively removing most of the
CH2Cl2, before the flask was taken back into the drybox where
the dark emerald green precipitate was filtered away from the
brownish filtrate. The precipitate was washed with pentane and
dried to yield 0.1062 g of (Fc2Bob)Ti[O2P(OC6H4NO2)2]2
1
(81%). H NMR (CDCl3): δ 8.12 (d, 9 Hz, 8H, OC6H4NO2
3,5-H), 7.48 (d, 8 Hz, 2H, biphenyl H-6), 7.43 (d, 9 Hz, 8H,
OC6H4NO2 2,6-H), 7.31 (m, 4H, biphenyl H-4,5), 7.10 (d, 8 Hz,
2H, biphenyl H-3), 5.17 (s, 2H, COCHCO), 4.76 (sl br, 2H, C5H4
H-2), 4.68 (sl br, 2H, C5H4 H-5), 4.57 (sl br, 4H, C5H4 H-3,4),
4.18 (s, 10H, C5H5), 3.98 (d, 14 Hz, 2H, CHH0), 3.04 (d, 14 Hz,
2H, CHH0). 13C{1H} NMR (CDCl3): δ 191.35, 184.32 (CO),
156.45, 144.47, 140.46, 134.97, 133.35, 129.98, 128.80, 127.84,
Cyclic Voltammetry. Cyclic voltammetry was performed in
the drybox using an EG&G Instruments PAR 283 or a BAS