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Electronic Supplementary Information

for

Modulation of the Nuclearity of Molecular Mg(II)-Phosphates: Solid-State

Structural Change Involving Coordinating Solvents

Biswajit Santra,a Ramakirushnan Suriya Narayanan,a Pankaj Kalita,b Debdeep Mandal,a Vivek Gupta,a Michael

Zimmer,c Volker Huch,c Vadapalli Chandrasekhar,*a,d David Scheschkewitz,*c Carola Schulzke*e and Anukul Jana*a

1. Content S1 2. General Considerations S2 3. Experimental Details S2 4. Crystallographic Details S6 5. Molecular Structures of Mg-Phosphate Monoesters S9 6. H-Bonded Molecular Structures of Mg-Phosphate Monoesters S10 7. H-Bonded Chemical Structures of Mg-Phosphate Monoesters S15 8. NMR Spectra S16 9. ESI-MS Data S23 10. FT-IR Data S26 11. CHN Data S30 12. References S31

aTata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad-500107, Telangana, India E-mail: ajana@tifrh.res.in bSchool of Chemical Sciences, National Institute of Science Education and Research, HBNI, Bhubaneswar-752050, India cKrupp-Chair of General and Inorganic Chemistry, Saarland University, 66123 Saarbrücken, Germany E-mail: scheschkewitz@mx.uni-saarland.de dDepartment of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India E-mail: vc@tifrh.res.in eInstitut für Biochemie, Universität Greifswald, Felix-Hausdorff-Straße 4, D-17487 Greifswald, Germany E-mail: carola.schulzke@uni-greifswald.de

Electronic Supplementary Material (ESI) for Dalton Transactions.This journal is © The Royal Society of Chemistry 2019

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General Considerations

Crystallographic Details

Single crystal X-ray diffraction data of 2, 3, 4a, 4b, 5, 6, and 7 were collected at low temperature (120 K) using a Rigaku

diffractometer with graphite-monochromated molybdenum Kα radiation, λ = 0.71073 Å. Data integration and reduction were

processed with CrysAlisPro software.S2 An empirical absorption correction was applied to the collected reflections with SCALE3

ABSPACK integrated within CrysAlisPro. The structures were solved by direct methods using the SHELXTS3 program and refined

by full matrix least-squares method based on F2 by using the SHELXLS4 program through the Olex2S5 interface. All non-hydrogen-

atoms were refined with anisotropic displacement parameters. The hydrogen atoms (except those of water) were refined

isotropically on calculated positions using a riding model with their Uiso values constrained to 1.5 Ueq of their pivot atoms for

terminal sp3 carbon atoms and 1.2 times for the aromatic carbon atoms.

For 7, the water molecule was constraint with DFIX for O-H and H…H distances. For 2, the lattice solvent molecule present in

the structure is heavily disordered. The PLATON/SQUEEZES6 program was used to get rid of the respective electron density

entirely. This yielded a total of 161 electrons per unit cell and total void volume of 739 Å3 which corresponds to one DMF

molecule per formula. Further, two disorders were taken care of in this structure. One DMF is disordered completely over two

positions (flipped) with occupancies of 80% and 20% respectively. The two partially occupied molecules were constrained using

SAME/SIMU/DELU. The tBu group of one phosphate ligand is disordered over two positions, again with ca. 80% to 20%

occupancies. All atoms of the tBu group were constrained using SIMU/DELU. For 3, the presence of disordered lattice solvent

molecules resulted in large total void volume in the structure. The PLATON/SQUEEZES6 program was used to get rid of the

respective diffuse electron density which yielded in total 41 electrons per unit cell and total void volume of 1538 Å3. This would

fit a bit more than two waters per unit cell, i.e. 2/3 per formula. For 4a, the tBu group is disordered over two positions. This was

modelled with occupancies of ca. 82% and 18%. Restraints or constraints were not needed in this structure.

For 5, both the tBu groups are disordered, as is one phenyl substituent and the entire chloroform. The present four individual

disorders were treated with a combination of SAME/SIMU/DELU constraints or with SADI/SIMU/DELU constraints. There exists

further some electron density which did not make sense at all. The extra electron density was therefore again SQUEEZED.

For 6, SQUEEZE was used to get rid of electron density which could not be refined sufficiently well to result in chemically

reasonable ions or molecules. The SQUEEZE/PLATONS6 routine yielded in total 1849 electrons per unit cell and total void

volume of 5503 Å3. This would fit roughly 100 water molecules per unit cell which is a comparatively large value (these are

roughly fife water per Mg, in addition to the coordinated ones). Also, one of the tBu groups is disordered (ca. 76% vs. 24%,

treated with constraints: SADI/SIMU/DELU). This time it is disordered not by rotation but by a bend, which does not make much

sense chemically. It could be argued that this is due to the very high symmetry and slight deviations of the atom positions on

symmetry generated atoms and that it might be better to go to a space group with lower symmetry. All hydrogen atoms on the

coordinated and lattice water molecules were located but then constrained with respect to the O-H and H…H distances and

with respect to their displacement parameters which were made dependent on their parent oxygen atoms (1.5 times). The

hydrogen atoms on O18 are the most precarious ones. The O18 resides at a special crystallographic position and is ‘rotating’ by

90° so that the hydrogen atoms are in two different orientations with half occupancy each (all four generated from one H in the

asymmetric unit).

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All crystallographic data were deposited with the Cambridge Crystallographic Data Centre, CCDC, 12 Union Road, Cambridge

CB21EZ, UK. These data can be obtained free of charge on quoting the depository number as listed in the crystallographic table

by FAX (+44-1223-336-033), email (deposit@ccdc.cam.ac.uk) or their web interface (at http://www.ccdc.cam.ac.uk). Crystal and

refinement data for compounds 2, 3, 4a, 4b, 5, 6, and 7 are in Table S1.

S4

Table S1. Crystal and refinement data for compounds 2, 3, 4a, 4b, 5, 6 and 7.

Compound 2 3 4a 4b 5 6 7

Code No aj0073 aj0008

aj0116 aj0120 aj0477 aj0270 aj0215

CCDC number 1866871 1866862

1866872 1866873 1866875 1866874 1866861

Empirical formula C168H188Mg4 N8O24P4

C252H318Mg6N12O54P6

C78H95Mg2N2O18P2 C41H50MgNO8P C158 H210 Cl6 Mg4N4O44P4

C288H354Cl2Mg9O77P8 C108H114Mg2N8O14P2

Fw 2924.37 4710.85 1459.11 740.10 3303.11 5585.14 1858.63

Temp. (K) 120.00(10) 120.00(10) 119(2) 120.(2) 148(2) K 120 .00(2) 120.(2)

Crystal system Monoclinic Trigonal Monoclinic Monoclinic Triclinic tetragonal Monoclinic

space group C2/c R-3 P21/c P21/n P-1 P4/n P21/n

a (Å) 29.9635(10) 35.8954(11) 31.610(6) 18.4495(10) 10.49570(10) 29.2437(5) 18.6977(5)

b (Å) 18.7967(5) 35.8954(11) 10.344(2) 10.4526(4) 20.6949(3) 29.2437(5) 13.5431(4)

c (Å) 32.9183(11) 17.7162(5) 23.225(5) 21.1252(10) 21.1795(3) 22.0280(5) 19.4511(6)

α (°) 90 90 90 90 87.4830(10) 90 90

β (°) 120.910(5) 90 91.52(3) 108.412(6) 76.5730(10) 90 104.515(3)

γ (°) 90 120 90 90 83.5070(10) 90 90

V (Å3) 15906.9(11) 19768.7(13) 7591(3) 3865.4(3) 4445.16(10) 18838.2(8) 4768.3(2)

Z 4 3 4 4 1 2 2

Dcalcd(Mg m−3) 1.221 1.187 1.277 1.272 1.234 0.985 1.295

μ (mm−1) 0.133 0.130 0.144 0.140 0.221 0.129 0.129

2θ range (°) 5.206 to 52.998 5.724 to 58.366 5.76 to 50.998 5.122 to 52.998 4.948 to 58.2 5.352 to 53 5.27 to 52.998

Reflections collected

75276 39891 26413 36715 100352 139116 51169

Independent reflections

16454 10049 12928 7984 20783 19503 9858

Data/ restraints/ parameters

16454 / 174 / 1030

10049/0/527 12928/99/1024 7984/0/504 20783 / 627 / 1254 19503 / 159 / 976 9858/3/619

GOF 1.039 1.038 1.214 1.074 1.090 1.031 1.036

R1[I0>2σ(I0)] 0.0540 0.0478 0.1476 0.0456 0.0412 0.0829 0.0412

wR2(all data) 0.1459 0.1115 0.3547 0.1159 0.1057 0.2124 0.0984

Largest diff. peak and hole (e Å−3 )

0.640 and -0.66

0.87 and -0.42 0.83 and -1.15 0.414 and -0.552 0.47 and -0.33 0.614 and -0.415 0.38 and -0.39

S5

Molecular Structures of Mg-Phosphate Monoesters

Figure S1. Molecular structure of 4b at the 50 % probability level. All H-atoms except those of water, two o-CHPh2, and p-tBu moieties were omitted for clarity reasons.

Figure S2. Molecular structures of tetranuclear Mg(II)-phosphate with the encapsulated chloride ion (top), mononuclear Mg(II)-phosphate (bottom left), and chloromagnesium cation (bottom right) as components of 6 at the 50 % probability level. All H-atoms except those on water, two o-CHPh2, and p- tBu moieties were omitted for clarity reasons.

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H-Bonded Molecular Structures of Mg-Phosphate Monoesters

Figure S4. open caged dodecanuclear water cluster inside the 3.

Figure S5. Icosahedral water cluster inside the 3 ring.

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Figure S6. Molecular structure of 3 with six non-coordinating water molecules.

Figure S7. Molecular structure of 3 with six non-coordinating water molecules where all the organic part of the ligands have been removed for clarity.

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Figure S8. Complete molecular structure of 6 comprising ring tetranuclear Mg-phosphate monoester, encapsulated chloride anion, Mg(II)-monochloride cation, and four mononuclear Mg-phosphate monoester.

Figure S9. H-bonded molecular structures of ring tetranuclear Mg-phosphate monoester with encapsulated chloride anion with the organic part of the ligand (left) and without the organic part of the ligand (right) of 6.

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Figure S10. Different view of H-bonded molecular structures of ring tetranuclear Mg-phosphate monoester with encapsulated chloride anion with the organic part of the ligand of 6.

Figure S11. H-bonded molecular structures of Mg(II)-monochloride cation stabilized by four mononuclear Mg-phosphate monoester of 6.

S10

Figure S12. Solid state pi-pi stacking interaction in complex 7 leading to 1D polymeric chain.

S11

H-Bonded Chemical Structures of Mg-Phosphate Monoesters

ArOP

OO

O

ArOPO

O

O

ArO

P

O

O

O

ArOP

Ow

OO

Mg

Mg

Mg

Mg

Od

Od

Ow

Od

Od

O

Ow

ArO

P O

O O

Mg

Mg

ArO P O

O

O

Od

Ow

Od Ow

Ow

Od

Od

Od

OdOd

Od

Ow

Ow

Ow

Ow

Ow

Ow

Ow

Ow

Ow

Ow

Ow

Ow

Scheme S1. H-bonded chemical structures of 3 (Od = DMF, Ow = water).

ArO P

O

O

O

ArOP

O

O

O

ArO

P OO

O

ArO

P

Ow1

O

O

MgMg

Mg

Mg

Ow1

Ow1

Ow1

Ow1

Ow3

O

Ow1

Mg

Mg

ArO

PO

OOOw1

Ow1

Ow2 Ow2

Ow3

Ow1

Ow1

Ow1

Ow1Ow3

Ow2

Ow2

Ow3

Ow1

Ow1

Ow1

Ow1

Cl

Ow2Cl

Ow3

Mg

ArO

PO

O

O

Ow2

Ow2

Ow2

Ow2Ow2

Mg

Ar

O

P

O

OO

Ow2

Ow2

Ow2

Ow2

Ow2

Mg

ArO

P O

O

O

Ow2

Ow2

Ow2 Ow2

Ow2

Ow2

Ow2

Ow2

Ow2

Ow2Ow2

Ow2

Ow2

Scheme S2. H-bonded chemical structures of 6, ring tetranuclear Mg-phosphate monoester with encapsulated chloride anion (left) and Mg(II)-monochloride cation stabilized by four mononuclear Mg-phosphate monoester (right) (Ow = water).

S12

NMR Spectra

Figure S12: 31P{1H} NMR spectrum of 2 in CDCl3 at room temperature.

Figure S13. CP-MAS 31P{1H} NMR spectrum of 2 at room temperature.

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Figure S14. 31P{1H} NMR spectrum of 3 in CDCl3 at room temperature.

Figure S15. CP-MAS 31P{1H} NMR spectrum of 3 at room temperature.

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Figure S16. 31P{1H} NMR spectrum of 4 in CDCl3 at room temperature.

Figure S17. 31P{1H} NMR spectrum of 4 in CDCl3 at room temperature.

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Figure S18. CP-MAS 31P{1H} NMR spectrum of 4 at room temperature.

Figure S19. 31P{1H} NMR spectrum of 5 in CDCl3 at room temperature.

S16

Figure S20. CP-MAS 31P{1H} NMR spectrum of 5 at room temperature.

Figure S21. 31P{1H} NMR spectrum of 6 in CDCl3 at room temperature.

S17

Figure S22. CP-MAS 31P{1H} NMR spectrum of 6 at room temperature.

Figure S23. 31P{1H} NMR spectrum of 7 in CDCl3 at room temperature.

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Figure S24. CP-MAS 31P{1H} NMR spectrum of 7 at room temperature.

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ESI-MS

Figure S25. ESI-MS of 3.

Figure S26. ESI-MS of 4.

S20

Figure S27. ESI-MS of 4.

Figure S28. ESI-MS of 5.

S21

Figure S29. ESI-MS of 6.

Figure S30. ESI-MS of 6.

S22

FT-IR Spectra

Figure S31. FT-IR spectrum of 2.

Figure S32. FT-IR spectrum of 3.

S23

Figure S33. FT-IR spectrum of 4a.

Figure S34. FT-IR spectrum of 4b.

S24

Figure S35. FT-IR spectrum of 5.

Figure S36. FT-IR spectrum of 6.

S25

Figure S37: FT-IR spectrum of 7.

S26

Elemental Analysis

Figure S59: CHN data for 3 (BS-271A, top), 2 (BS-299C, middle), 4b (BS-299M, middle), 7 (BS-298A, middle), 6 (BS-299BS, middle), 4a (BS-280A, bottom), 5 (BS-306, bottom).

S27

REFERENCES

S1 D. Mandal, B. Santra, P. Kalita, N. Chrysochos, A. Malakar, R. S. Narayanan, S. Biswas, C. Schulzke, V. Chandrasekhar and

A. Jana, Chemistry Select 2017, 2, 8898–8910.

S2 CrysAlisPro: Rigaku Oxford Diffraction (1995-2017). Oxford Diffraction Ltd, Abingdon, Oxfordshire, England.

S3 G. M. Sheldrick, Acta Cryst. 2015, A71, 3‒8.

S4 G. M. Sheldrick, Acta Cryst. 2015, C71, 3‒8.

S5 O. V. Dolomanov, L. J. Bourhis, R. J. Gildea, J. A. K. Howard and H. Puschmann, J. Appl. Crystallogr. 2009, 42, 339‒341.

S6 A. L. Spek, J. Appl. Cryst., 2003, 36, 7‒13.