Optically Active Polyoxotungstates with Chiral Organophosphonates
addition of KHSO4 (pHՅ1), the product was extracted with ethyl
acetate (10ϫ15 mL). The organic phase was dried with MgSO4,
and the solvent was removed under vacuum to afford a yellow solid
(s), 908 (s), 877 (s), 838 (s), 762(s), 552 (m), 457 (w) cm–1. 1H NMR
(300 MHz, CD3CN, 28 °C): δ = 7.82 (m, 4 H, Ar-H), 7.71 (m, 4
H, Ar-H), 7.38 (m, 8 H, Ar-H), 5.92 (br. d, 3J = 9.30 Hz, 2 H,
NH), 4.38–4.10 (m, 8 H, CHP, CH2O, CH), 3.12 (m, 24 H, NCH2),
(983 mg, 2.8 mmol, 71% yield). FTIR (KBr): ν =3299 (s), 2930 (w),
˜
3
3053 (w), 3020 (w), 2998 (w), 2980 (w), 2951 (w), 2936 (w), 2891
(w), 1738 (m), 1685 (s), 1540 (s), 1477 (w), 1455 (m), 1447 (m),
1.62 (m, 24 H, CH2), 1.39 (m, 30 H, CH2 and CH3), 0.97 (t, J =
7.33 Hz, 36 H, CH3) ppm. 13C{1H} NMR (75.47 MHz, CD3CN,
1379 (m), 1308 (m), 1276 (m), 1262 (m), 1240 (m), 1194 (m), 1175 28 °C): δ = 156.78 (2 C), 145.40 (4 C), 142.07 (4 C), 128.68 (4 C),
(m), 1104 (m, br.), 1080 (m), 1051 (m), 1021 (m), 1002 (m), 1005 128.28 (4 C), 126.61 (4 C), 120.90 (4 C), 67.57 (2 C), 59.34 (12 C),
(m), 940 (m), 932 (m), 918 (m), 762 (m), 744 (m), 731 (m), 705 (w),
48.08 (2 C), 30.89 (2 C), 24.41 (12 C), 20.38 (12 C), 17.90 (2 C),
13.93 (12 C) ppm. 31P{1H} NMR (79.49 MHz, CD3CN, 28 °C): δ
= 20.99 (s, 2 P) ppm. 183W NMR (16.67 MHz, CD3CN/CH3CN,
25 °C): δ = 103.11 (s, WC, 2 W), –111.88 (s, WA, 2 W), –113.17 (s,
1
641 (w, br.), 569 (w), 542 (w), 526 (m), 408 (w), 469 (m) cm–1. H
3
NMR (300 MHz, [D6]DMSO, 28 °C): δ = 7.88 (d, J = 7.35 Hz, 2
3
3
H, Ar-H), 7.76 (t, J = 6.71 Hz, 2 H, Ar-H), 7.41 (t, J = 7.38 Hz,
2 H, Ar-H), 7.33 (m, 2 H, Ar-H), 4.22 (m, 3 H, CH2O and CH), WAЈ, 2 W), –145.11 [d, 2J(W,P) = 8.97 Hz, WB, 2 W], 145.24 [d,
3
3
3.75 (m, 1 H, CH), 1.23 [dd, J = 7.49 Hz, J(H,P) = 15.90 Hz, 3
H, CH3] ppm. 13C{1H} NMR (75.47 MHz, [D6]DMSO, 28 °C): δ
= 155.6 (1 C), 143.9 (2 C), 140.7 (2 C), 127.3 (2 C), 125.4 (2 C),
2J(W,P) = 8.97 Hz, WBЈ, 2 W] ppm. MS (ESI–, CH3CN): m/z =
1020. C82H140KN5O42P2SiW10 (3835.52): calcd. C 25.36, H 3.96, N
1.85; found C 26.02, H 3.70, N 1.85. UV: λ (logε) = 205 (5.18), 262
120.1 (2 C), 65.8 (1 C), 46.7 (1 C), 44.3 [1J(C,P) = 154.6 Hz, 1 C], (4.74), 286 (4.38), 299 (4.33) nm.
16.0 (1 C) ppm. 31P{1H} NMR (121.50 MHz, [D6]DMSO, 28 °C):
(R)- and (S)-(TBA)3K[{C6H5CH2OC(O)NHCH(CH3)PO}2(γ-
SiW10O36)] (2): K8[γ-SiW10O36]·12H2O (0.7 g, 0.24 mmol) and (R)-
or (S)-II (122 mg, 0.48 mmol) were used to afford the product
δ = 22.42 (s, 1 P) ppm. UV/Vis: λ (logε) = 195 (5.34), 266 (4.11),
289 (3.58), 300 (3.62) nm.
(555 mg, 0.15 mmol, 63% yield). FTIR (KBr): ν = 3431 (br.), 2962
˜
(S)- and (R)-C6H5CH2OCONHCH(CH3)PO(OH)2 (III): To a solu-
tion of (R)- or (S)-1-aminoethylphosphonic acid (I; 200 mg,
1.60 mmol) dissolved in H2O (1 mL) was added a solution of ben-
zyloxycarbonyl succinimide (400 mg, 1.61 mmol) in acetonitrile
(400 µL) whilst stirring. Triethylamine (300 µL) was used to achieve
and maintain pH 8. After one night stirring, the organic solvent
was removed under vacuum, and the remaining solution was di-
luted 1:1 with water. The excess amount of benzyloxycarbonyl suc-
cinimide was removed by extraction with diethyl ether (10ϫ4 mL).
The aqueous phase was acidified to pHՅ1 with diluted H2SO4,
and the product was extracted with ethyl acetate (10ϫ8 mL). The
organic layer was dried with MgSO4, and the solvent was removed
under vacuum to obtain the product (310 mg, 1.20 mmol, 75%
(m), 2874 (w), 1717 (w), 1653 (w), 1484 (m), 1457 (w, sh.), 1384
(w), 1269 (w), 1222 (w), 1154 (w), 1059 (w), 1006 (w), 966 (s), 945
(m), 909 (s), 885 (s), 840 (s), 761 (s, br.), 546 (w, br.), 453 (w) cm–1.
1H NMR (300 MHz, CD3CN, 28 °C): δ = 7.37 (m, 10 H, Ar-H),
5.80 (m, 2 H, NH), 5.09 (m, 4 H, CH2), 4.00 (m, 2 H, CH), 3.13
(m, 24 H, NCH2), 1.64 (m, 24 H, CH2), 1.40 (m, 30 H, CH2 and
CH3), 0.99 (t, 3J = 7.24 Hz, 36 H, CH3) ppm. 13C{1H} NMR
(75.47 MHz, CD3CN, 28 °C): δ = 157.15 (2 C), 138.02 (2 C), 129.43
(4 C), 128.79 (2 C), 128.63 (4 C), 67.11 (2 C), 58.42 (12 C), 45.06
[1J(C,P) = 169.78 Hz, 2 C], 24.36 (12 C), 20.33 (12 C), 16.76 (2 C),
14.04 (12 C) ppm. 31P{1H} NMR (121.50 MHz, [D6]DMSO,
28 °C): δ = 21.51 (s, 2 P) ppm. 183W NMR (16.67 MHz, CD3CN/
CH3CN, 25 °C): δ = –105.92 (s, WC, 2 W), –114.67 (s, WA, 2 W),
yield). FTIR (KBr): ν = 3295 (s), 3032 (w), 2949 (w), 1689 (s, br.),
˜
2
–115.80 (s, WAЈ, 2 W), –147.84 [d, J(W,P) = 9.65 Hz, WB, WBЈ, 4
1540 (s), 1455 (m), 1428 (w), 1312 (m), 1277 (m), 1258 (m), 1225
(m), 1190 (m), 1165 (m), 1116 (m), 1082 (m), 1056 (m), 1004 (m),
941 (m), 815 (w), 779 (w), 739 (w), 714 (w), 694 (m) cm–1. 1H NMR
(250 MHz, CD3CN/[D6]DMSO, 25 °C): δ = 7.32 (s, 5 H, Ar-H),
6.42 (m, 1 H, NH), 5.05 (m, 2 H, CH2), 3.87 (m, 1 H, CH), 1.26
[dd, 3J(H,H) = 7.32 Hz, 3J(H,P) = 16.05 Hz, 3 H, CH3] ppm.
13C{1H} NMR (75.47 MHz, CD3CN/[D6]DMSO, 28 °C): δ = 173.8
(1 C), 138.1 (1 C), 129.3 (2 C), 128.8 (1 C), 128.7 (2 C), 66.9 (1 C),
45.3 [1J(C,P) = 155.43 Hz, 1 C], 26.1 (1 C) ppm. 31P{1H} NMR
(121.50 MHz, CD3CN/[D6]DMSO, 28 °C): δ = 24.13 (s, 1 P) ppm.
UV/Vis (CH3CN): λ (logε): 239 (3.86) nm.
W] ppm. 29Si{1H} NMR (79.50 MHz, CH3CN\CD3CN): δ = –85.8
(s,
1 Si) ppm. MS (ESI–, CH3CN/H2O): m/z = 964.6.
C68H132KN5O42P2SiW10 (3659.31): calcd. C 22.32, H 3.64, N 1.91;
found C 22.60, H 3.67, N 1.99. UV: λ (logε) = 239 (4.46) nm.
(TBA)3K[{HOC(O)CH2PO}2(γ-SiW10O36)] (5): K8[γ-SiW10O36]·
12H2O (600 mg, 0.20 mmol) and HOC(O)CH2PO(OH)2 (57 mg,
0.4 mmol) were used to afford the product (514 mg, 0.15 mmol,
75% yield). FTIR (KBr): ν = 2961 (m), 2936 (m), 2872 (m), 1735
˜
(m, br.), 1654 (m, br.), 1484 (m, br.), 1380 (m), 1223 (m), 1154 (m),
1109 (m), 1068 (m), 1011 (m), 969 (m), 943 (s), 912 (s), 886 (s), 839
(m), 756 (s), 559 (m), 524 (m), 457 (m), 416 (m) cm–1. 1H NMR
General Procedure for the Preparation of Compounds 1, 2, 5, and
8:[39] In a round-bottomed flask, K8[γ-SiW10O36]·12H2O (500–
700 mg, 0.24 mmol) was suspended in acetonitrile (15 mL) with
TBABr (229 mg, 0.71 mmol). After stirring for 5 min, organophos-
phonic acid (2 equiv.) was added, followed by the slow addition of
HCl (4 , 4 equiv.) under vigorous stirring. The mixture was heated
at reflux overnight and filtered to remove insoluble reagents and
byproducts. The volume of the solution was reduced to 1 mL, upon
evaporation under vacuum, than water was added to precipitate
the product. The solid was finally washed with water and diethyl
ether on a fritted funnel and dried several hours under vacuum.
2
(300 MHz, CD3CN, 28 °C): δ = 3.14 (m, 24 H), 2.87 [d, J(H,P) =
23.02 Hz, 4 H], 1.64 (m, 24 H), 1.40 (m, 24 H), 0.99 (t, 3J =
7.34 Hz, 36 H) ppm. 13C{1H} NMR (75.47 MHz, CD3CN, 28 °C):
1
δ = 167.48 (2 C), 59.01 (12 C), 36.55 [d, J(C,P) = 144.50 Hz, 2 C],
24.41 (12 C), 20.40 (12 C), 13.90 (12 C) ppm. 31P NMR
2
(121.50 MHz, CD3CN, 28 °C): δ = 17.49 [t, J(P,H) = 22.90 Hz, 2
P] ppm. 183W NMR (16.67 MHz, CD3CN/CH3CN, 25 °C): δ =
–106.99 (s, WC, 2 W), –115.60 (s, WA, 4 W), –156.93 [d, 2J(W,P)
= 11.4 Hz, WB, 4 W] ppm. 29Si{1H} NMR (79.49 MHz, CD3CN/
CH3CN, 25 °C): δ = –86.4 (s, 1 Si) ppm. MS (ESI–, CH3CN): m/z
= 884. C52H114KN3O42P2SiW10 (3420.98): calcd. C 19.06, H 3.79,
N 1.57; found C 18.53, H 3.39, N 1.52.
(R)- and (S)-(TBA)3K[{C13H9CH2OC(O)NHCH(CH3)PO}2(γ-
SiW10O36)] (1): K8[γ-SiW10O36]·12H2O (700 mg, 0.24 mmol) and
(R)- or (S)-I (165 mg, 0.48 mmol) were used to afford the product
Deprotection Procedures
(754 mg, 83% yield). FTIR (KBr): ν = 2961 (m), 2932 (m), 2875
(m), 1719 (m), 1509 (m), 1483 (m), 1452 (m), 1379 (m), 1318 (w),
1267 (m), 1223 (m) 1153 (m), 1109 (m), 1051 (m), 1007 (m), 966
(R)- and (S)-(TBA)3K[{NH2CH(CH3)PO}2(γ-SiW10O36)] (3): In a
round-bottomed flask, (R)- or (S)-1 (700 mg, 0.18 mmol) was dis-
solved in CH3CN (6 mL). Et2NH (300 µL, 2.9 mmol) was added.
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Eur. J. Inorg. Chem. 2009, 5164–5174
© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjic.org
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