2718
W. Le6ason et al. / Polyhedron 20 (2001) 2711–2720
Ph3AsO (0.64 g, 2.0 mmol) in ethanol (10 cm3), the
solution evaporated to 10 cm3, and then refrigerated for
24 h. The white solid was filtered off and dried in
vacuo. Yield: 0.56 g, 58%. Anal. Found: C, 45.6; H, 3.5;
N, 3.7. Calc. for C38H36As2LaN3O12: C, 45.0; H, 3.6; N,
4.1%. IR (CsI disc, cm−1): 3400br, 1477s, 1307s,
1186w, 1089s, 1032m, 999m, 908s, 888s, 820m, 743s,
691s, 478s, 457m, 368s, 361s. 1H NMR (300 K, CDCl3):
7.3–7.8(m), 3.7(q, J=7 Hz), 1.20(t, J=7 Hz). \M
CD3NO2): 58.0 (W1/2, 1200 Hz); with excess Me3AsO
56.0 (W1/2, 80 Hz). \M (MeNO2, 10−3 mol dm−3) 157
V
−1 cm2 mol−1; with excess Me3AsO \M=220.
4.9. [Y(Me3AsO)6](NO3)3
Prepared as above from Y(NO3)3·6H2O (0.19 g, 0.5
mmol) and Me3AsO (0.408 g, 3.0 mmol). Yield: 0.29 g,
53%. Anal. Found: C, 19.6; H, 4.9; N, 3.9. Calc. for
C18H54As6N3O15Y: C, 19.8; H, 5.0; N, 3.9%). IR (CsI
disc, cm−1): 3010w, 1642w, 1358s, 1270m, 1095m, 926s,
877vs, 836s, 650s, 353s, 288m. 1H NMR (300 K,
CD3NO2): 2.55 (s). 13C{1H} NMR (300 K, MeNO2/
CD3NO2): 15.0(s). 89Y NMR (200 K, EtNO2/CDCl3):
112(s); with excess Me3AsO 133(s). \M (MeNO2, 10−3
mol dm−3) 180 V−1 cm2 mol−1; with excess Me3AsO
\M=240.
(CH2Cl2, 10−3 mol dm−3) 4 V−1 cm2 mol−1
.
4.6. [La(Ph3AsO)3(NO3)3]·Me2CO
A solution of La(NO3)3·6H2O (0.22 g, 0.50 mmol) in
boiling acetone (10 cm3) was added to a solution of
Ph3AsO (0.48 g, 1.5 mmol) in acetone (10 cm3), the
solution was evaporated to 10 cm3, then refrigerated for
24 h. The colourless crystals were filtered off and dried
in vacuo. Yield: 0.55 g, 85%. Anal. Found: C, 50.4; H,
3.7; N, 2.6. Calc. for C57H51As3LaN3O13: C, 50.7; H,
3.8; N, 3.1%. IR (CsI disc, cm−1): 3054w, 1702w,
1486s, 1454s, 1442s, 1363s, 1304s, 1226w, 1185w,
1163w, 1089m, 1070w, 1033m, 999w, 924w, 890s, 821m,
747s, 693s, 533m, 478s, 359s. 1H NMR (300 K, CDCl3):
7.2–7.65(m), 2.15(s). \M (CH2Cl2, 10−3 mol dm−3) 4
4.10. [La(Me3AsO)6](NO3)3
A boiling solution of La(NO3)3·6H2O (0.14 g, 0.33
mmol) in acetone (10 cm3) was added to a solution of
Me3AsO (0.27 g, 2.0 mmol) in acetone (10 cm3). The
solution was refrigerated overnight and the white solid
produced, filtered off and dried in vacuo. Yield: 0.21 g,
55%. Anal. Found: C, 19.2; H, 4.9; N, 4.2. Calc. for
C18H54As6LaN3O15: C, 19.0; H, 4.8; N, 3.7%. IR (CsI
disc, cm−1): 2936w, 1653w, 1359s, 1269w, 1091m,
V
−1 cm2 mol−1
.
4.7. [La(Ph3AsO)4(NO3)2]NO3·Me2CO
1
987w, 924s, 864vs, 847s, 836sh, 647s, 317s, 279m. H
A solution of La(NO3)3·6H2O (0.43 g, 1.0 mmol) in
boiling acetone (10 cm3) was added to a solution of
Ph3AsO (1.9 g, 6.0 mmol) in acetone (30 cm3), and the
mixture left at room temperature for 1 d. Colourless
crystals formed. Yield: 1.23 g, 73%. Anal. Found: C,
53.2; H, 4.2; N, 2.5. Calc. for C75H66As4LaN3O14: C,
53.6; H, 3.8; N, 2.6%. IR (CsI disc, cm−1): 3059w,
1707m, 1442s, 1361s, 1313s, 1228m, 1189m, 1089s,
1050w, 1036w, 999m, 925sh, 891s, 836w, 820m, 746s,
693s, 614w, 479s, 366s. 1H NMR (300 K, CDCl3):
7.2–7.7 (m), 2.15(s). \M (CH2Cl2, 10−3 mol dm−3) 21
NMR (300 K, CD3NO2): 2.3 (s). 13C{1H} NMR (200
K, EtNO2/CDCl3): 15.0 (s).
\
(MeNO2, 10−3
M
mol dm−3) 121 V−1 cm2 mol−1; with excess Me3AsO
\M=285.
4.11. [La(Me3AsO)2(H2O)(NO3)3]
A solution of La(NO3)3·6H2O (0.43 g, 1.0 mmol) in
boiling ethanol (10 cm3) was treated with Me3AsO (0.27
g, 2.0 mmol) in ethanol (10 cm3). The mixture was
refrigerated overnight and the white solid which sepa-
rated, filtered off and dried in vacuo. Yield: 0.12 g,
20%. Anal. Found: C, 12.4; H, 3.6; N, 6.4. Calc. for
C6H20As2LaN3O12: C, 11.7; H, 3.3; N, 6.8%. IR (CsI
disc, cm−1): 3400br, 3095w, 1620m, 1455m, 1407m,
1358m, 1322w, 1287s, 1266w, 1040m, 924m, 875s, 860s,
V
−1 cm2 mol−1
.
4.8. [Sc(Me3AsO)6](NO3)3
Scandium nitrate hydrate (0.17 g, 0.75 mmol) and
Me3AsO (0.61 g, 4.5 mmol) were dissolved separately in
ice-cold ethanol (10 cm3), the solutions mixed and
stirred for 1 h. The solution was concentrated in vacuo
to 10 cm3 and refrigerated overnight. The white solid
was filtered off and dried in vacuo. Yield: 0.18 g, 38%.
Anal. Found: C, 20.3; H, 5.1; N, 4.6. Calc. for
C18H54As6N3O15Sc: C, 20.7; H, 5.2; N, 4.0%. IR (CsI
disc, cm−1): 3010w, 1648w, 1364s, 1269m, 1111m,
1
850m, 822w, 736m, 644m, 595w, 323s, 285sh. H NMR
(300 K, CD3NO2): 2.2 (s), 2.6 (s).
4.12. X-ray crystallographic studies
Selected crystallographic details of the six com-
pounds studied are given in Table 6. Crystals which
were either small or of modest quality were obtained by
vapour diffusion using the liquids CH2Cl2/Et2O or
MeNO2/Et2O (Me3AsO complexes) with the sealed con-
tainers being held in the refrigerator. Data were
1
1048w, 925s, 873vs, 848s, 836sh, 648s, 396s, 303m. H
NMR (300 K, CD3NO2): 2.3(s). 13C{1H} NMR (300 K,
MeNO2/CD3NO2): 15.0(s). 45Sc NMR (300 K, MeNO2/