Synthesis, Structures and Properties of Alkaline-Earth Metal Salts of 4-Nitrophenylacetic Acid

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SUPPLEMENTARY INFORMATION

Synthesis, structures and properties of alkaline-earth metal salts of 4-nitrophenylacetic acid

BIKSHANDARKOIL R SRINIVASAN1*,KIRAN T DHAVSKAR1and CHRISTIAN NATHER2

1Department of Chemistry, Goa University, Goa 403206, India

2 Institut für Anorganische Chemie, Christian-Albreschts Universität Kiel, D-24098 Kiel, Germany

*E-mail:

Table of Contents

No / Contents / Page No.
1 / Table S1. Bond lengths and angles (Å, °) of 4-npa in 1-3 / 3
2 / Table S2. O-M-O bond angles [°] of 1-3 / 4
3 / Fig. S1. IR spectra of free 4-npaH compounds 1-4 / 5
4 / Fig. S2.IR spectra and TG-DTA curves of 1 / 5
5 / Fig. S3. TG-DTA curves for fresh and aged sample of 3 / 6
6 / Fig. S4.IR spectra of 3 / 7
7 / Fig. S5.TG-DTA profile of 2 / 7
8 / Fig. S6. IR spectra of 2 showing de- and rehydration / 8
9 / Fig. S7.Raman spectra of free acid, 1, 2, and 3 / 9
10 / Fig. S8. UV-Visible spectra of free acid,1, 2, and 3 / 9
11 / Fig. S9. Details of H-bonding in 1& crystallographic packing / 10
12 / Fig. S10. Binding modes of 4-npa ligands & {CaO8} polyhedron in 2 / 11
13 / Fig. S11. Formation of discrete dimers in 2 / 12
14 / Fig. S12. Binding modes of 4-npa ligands & {SrO9} polyhedron in 3 / 13

Table S1. Bondlengthsand angles[Å, o] for 4-nitrophenylacetate in compounds 1-3

Bond lengths / Bond angles
[Mg(H2O)6](4-npa)2·4H2O (1)
C1-O5 / 1.239(3) / C5-C6 / 1.372(3) / O5-C1-O4 / 124.36(19) / C5-C6-C7 / 122.3(2)
C1-O4 / 1.252(2) / C6-C7 / 1.372(3) / O5-C1-C2 / 119.05(19) / C5-C6-N1 / 119.3(2)
C1-C2 / 1.521(3) / C6-N1 / 1.463(3) / O4-C1-C2 / 116.59(18) / C7-C6-N1 / 118.47(19)
C2-C3 / 1.506(3) / C7-C8 / 1.373(3) / C3-C2-C1 / 115.05(18) / C6-C7-C8 / 118.6(2)
C3-C4 / 1.386(3) / N1-O7 / 1.216(2) / C4-C3-C8 / 118.5(2) / C3-C8-C7 / 121.2(2)
C3-C8 / 1.384(3) / N1-O6 / 1.228(2) / C4-C3-C2 / 121.1(2) / O7-N1-O6 / 122.65(19)
C4-C5 / 1.379(3) / C8-C3-C2 / 120.4(2) / O7-N1-C6 / 119.04(19)
C3-C4-C5 / 121.2(2) / O6-N1-C6 / 118.3(2)
C6-C5-C4 / 118.2(2)
[Ca(4-npa)2( H2O)2] (2)
C1-C6 / 1.390(3) / C11-C12 / 1.390(3) / C6-C1-C2 / 118.4(2) / C12-C11-C16 / 119.2(2)
C1-C2 / 1.402(3) / C11-C16 / 1.390(4) / C6-C1-C7 / 118.8(2) / C12-C11-C17 / 121.1(2)
C1-C7 / 1.518(3) / C11-C17 / 1.516(3) / C2-C1- C7 / 122.7(2) / C16-C11-C17 / 119.7(2)
C2-C3 / 1.385(4) / C12-C13 / 1.395(3) / C1-C2-C3 / 120.6(2) / C11-C12-C13 / 120.7(2)
C3-C4 / 1.378(4) / C13-C14 / 1.382(4) / C4-C3-C2 / 119.4(2) / C14-C13-C12 / 118.4(2)
C4-C5 / 1.389(4) / C14-C15 / 1.384(3) / C3-C4-C5 / 122.0(2) / C13-C14-C15 / 122.5(2)
C4-N1 / 1.464(3) / C14-N11 / 1.467(3) / C3-C4-N1 / 119.0(2) / C13-C14-N11 / 119.1(2)
C5-C6 / 1.392(3) / C15-C16 / 1.388(3) / C5-C4-N1 / 118.9(2) / C15-C14-N11 / 118.4(2)
C7-C8 / 1.513(3) / C17-C18 / 1.517(3) / C4-C5-C6 / 117.7(2) / C14-C15-C16 / 118.0(2)
C8-O1 / 1.258(3) / C18-O11 / 1.253(3) / C1-C6-C5 / 121.9(2) / C15-C16-C11 / 121.3(2)
C8-O2 / 1.260(3) / C18-O12 / 1.257(3) / C8-C7-C1 / 116.7(2) / C11-C17-C18 / 113.87(19)
N1-O4 / 1.223(3) / N11-O13 / 1.217(3) / O1-C8-O2 / 121.6(2) / O11-C18-O12 / 122.2(2)
N1-O3 / 1.224(3) / N11-O14 / 1.226(3) / O1-C8-C7 / 119.2(2) / O11-C18-C17 / 118.8(2)
O2-C8-C7 / 119.1(2) / O12-C18-C17 / 118.99(19)
O4-N1-O3 / 122.4(2) / O13-N11-O14 / 122.5(2)
O4-N1-C4 / 118.6(3) / O13-N11-C14 / 118.8(2)
O3-N1-C4 / 119.0(2) / O14-N11-C14 / 118.8(2)
[Sr(4-npa)2( H2O )3]·4.5H2O (3)
C1-O2 / 1.229(5) / C5-C6 / 1.354(7) / O2-C1-O1 / 122.9(4) / C5-C6-C7 / 121.2(5)
C1-O1 / 1.245(5) / C6-C7 / 1.365(7) / O2-C1-C2 / 119.7(4) / C5-C6-N1 / 119.0(5)
C1-C2 / 1.520(7) / C6-N1 / 1.469(6) / O1-C1-C2 / 117.4(4) / C7-C6-N1 / 119.8(5)
C2-C3 / 1.489(6) / C7-C8 / 1.368(7) / C3-C2-C1 / 114.1(4) / C6-C7-C8 / 119.3(5)
C3-C4 / 1.367(7) / N1-O3 / 1.211(6) / C4-C3-C8 / 117.8(5) / C7-C8-C3 / 120.9(5)
C3-C8 / 1.377(7) / N1-O4 / 1.223(6) / C4-C3-C2 / 121.5(5) / O3-N1-O4 / 122.8(5)
C4-C5 / 1.367(7) / C8-C3-C2 / 120.7(5) / O3-N1-C6 / 120.1(5)
C5-C4-C3 / 122.2(5) / O4-N1-C6 / 117.2(5)
C6-C5-C4 / 118.6(5)

Table S2. Selected bond angles [o] for 1, 2 and 3

[Mg(H2O)6](4-npa)2·4H2O (1)
O2-Mg1-O2i / 180.0 / O3-Mg1-O3i / 180.0 / O2-Mg1-O1i / 91.36(7)
O2-Mg1-O3 / 91.63(7) / O2-Mg1-O1 / 88.64(7) / O1i -Mg1-O2i / 88.64(7)
O3-Mg1-O2i / 88.37(7) / O1-Mg1-O2i / 91.36(7) / O3-Mg1-O1i / 88.39 (7)
O2-Mg1-O3i / 88.37(7) / O3-Mg1-O1 / 91.61(7) / O1i -Mg1-O3i / 91.61(7)
O2i -Mg1-O3i / 91.63(7) / O1-Mg1-O3i / 88.39 (7) / O1-Mg1-O1i / 180.0
[Ca(H2O)2(4-npa)2] (2)
O11ii-Ca1-O2iii / 148.36(6) / O11ii-Ca1-O1 / 79.48(6) / O1-Ca1-O2 / 50.98(5)
O11ii-Ca1-O21 / 78.59(6) / O2iii-Ca1-O1 / 125.20(6) / O11ii-Ca1-O11 / 73.58(6)
O2iii-Ca1-O21 / 83.70(6) / O21-Ca1-O1 / 149.05(6) / O2iii-Ca1-O11 / 128.43(6)
O11ii-Ca1-O 22 / 84.03(6) / O22-Ca1-O1 / 91.16(7) / O21-Ca1-O11 / 79.18(6)
O 2iii-Ca1-O 22 / 76.72(6) / O12-Ca1-O1 / 85.72(7) / O22-Ca1-O11 / 154.84(6)
O21-Ca1-O22 / 107.91(7) / O11ii-Ca1-O2 / 126.21(6) / O12-Ca1-O11 / 50.83(5)
O11ii-Ca1-O12 / 124.40(6) / O2iii-Ca1-O2 / 74.22(6) / O1-Ca1-O11 / 73.84(6)
O2iii-Ca1-O12 / 80.82(6) / O21-Ca1-O2 / 155.19(6) / O2-Ca1-O11 / 105.72(6)
O21-Ca1-O12 / 88.90(7) / O22-Ca1-O2 / 78.23(6)
O22-Ca1-O12 / 150.00(6) / O12-Ca1-O2 / 76.70(6)
[Sr(H2O)3(4-npa)2]·4.5H2O (3)
O1iv-Sr1-O1v / 157.18(16) / O6vi-Sr1-O2vi / 76.47(16) / O2vi-Sr1-O1 / 77.68(11)
O1iv-Sr1-O6 / 80.45(13) / O2-Sr1-O2vi / 95.33(19) / O1vi-Sr1-O1 / 98.22(14)
O1v-Sr1-O6 / 89.34(11) / O1iv-Sr1-O1vi / 123.80(11) / O1iv-Sr1-O5 / 78.58(8)
O1iv –Sr1-O6vi / 89.34(11) / O1v-Sr1-O1vi / 72.71(11) / O1v-Sr1-O5 / 78.58(8)
O1v -Sr1-O6vi / 80.45(13) / O6-Sr1-O1vi / 151.40(15) / O6-Sr1-O5 / 63.39(13)
O6-Sr1-O6vi / 126.8(3) / O6vi-Sr1-O1vi / 73.05(13) / O6vi-Sr1-O5 / 63.39(13)
O1iv-Sr1-O2 / 120.29(10) / O2-Sr1-O1vi / 77.68(11) / O2-Sr1-O5 / 132.34(10)
O1v-Sr1-O2 / 76.24(11) / O2vi-Sr1-O1vi / 48.06(9) / O2vi-Sr1-O5 / 132.34(10)
O6-Sr1-O2 / 76.47(16) / O1iv-Sr1-O1 / 72.71(11) / O1vi -Sr1-O5 / 130.89(7)
O6vi-Sr1-O2 / 146.85(11) / O1v-Sr1-O1 / 123.80(11) / O1-Sr1-O5 / 130.89(7)
O1iv-Sr1-O2vi / 76.24(11) / O6 -Sr1-O1 / 73.05(13) / Sr1-O1-Sr1iv / 107.29(11)
O1v-Sr1-O2vi / 120.30(10) / O6vi-Sr1-O1 / 151.39(15)
O6-Sr1-O2vi / 146.85(11) / O2-Sr1-O1 / 48.07(9)
Symmetry transformations used to generate equivalent atoms: i)-x, -y-1, -z+1; ii) -x+1, y+1, -z+1; iii) -x+2,-y+1, -z+1, iv)-x+1, -y, -z; v) x, -y, z+1/2; vi) -x+1, y, -z+1/2

Figure S1. IR spectra of 4-nitrophenylacetic acid (4-npaH), 1, 2, 3, and 4

Figure S2.IR spectra supporting gradual weightloss in 1

Figure S3. TG-DTA curves for fresh (top) and old/aged (bottom) sample of 3indicating gradual loss of water from compound

Figure S4.IR spectra of 3 showing changes in the region 3000–3500 cm-1 over a period of time indicating gradual loss of water from the sample

Figure S5.The TG-DTA profile of compound 2

Figure S6.IR spectra of 2 showing stability at 100oC (top). Dehydrated compound (2a) can be rehydrated (2b) (bottom)

Figure S7. Raman spectra of free acid, 1, 2 and 3

Figure S8.The optical spectra of 4-npaH, 1, 2 and 3.

Figure S9. H-bonding around lattice water (O8) (top left); H-bonding around lattice water (O9) (top right); H-bonding around the unique 4-npa anion (middle). A view along b axis showing the crystallographic packing of cations (shown as polyhedra) and anions as alternating layers (bottom).

Figure S10. The μ2-bridging tridentate coordination of the first unique ligand (O1, O2) with a Ca∙∙∙Caii separation of 3.989Å (topleft); The μ2-bridging tridentate coordination mode of the second unique ligand (O11, O12) resulting in Ca∙∙∙Cai separation of 4.009 Å (topright); A view of the distorted square antiprismatic coordination polyhedron around Ca(II) (bottom). Symmetry code: i) -x+1, y+1, -z+1; ii) -x+2, y+1, -z+1

Figure S11. The tricyclic dimetallic-dicarboxylate unit in2 with Ca∙∙∙Caii separation of 3.989 Å due to the first unique ligand (O1, O2) (top). For clarity the second unique lignad (O11, O12) and the terminal waters O21 and O22 around each Ca(II) are not shown. The tricyclic dimetallic-dicarboxylate unit in2 with Ca∙∙∙Caii separation of 4.009 Å due to the second unique ligand (O11, O12)(bottom).

Figure S12. A view of the coordination polyhedron around Sr(II).Symmetry code: i) -x+1, -y, -z; ii) x, -y, z+1/2; iii) -x+1, y, -z+1/2 (top); The μ2-bridging tridentate coordination of the unique ligand (O1, O2) with a Sr∙∙∙Sri separation of 4.194(1)Å (middle) resulting in the formation of a 1-D chain polymer extending along c axis(bottom)