1

Supporting Information

Design and chemical synthesis of a novel coumarin-based framework as a potential

chemosensor of a neurotoxic insecticide, azamethiphos

Aman K.K. Bhasina*, Pushap Rajb, Pooja Chauhanc, Sanjay K. Mandald, Savita Chaudharyc

Narinder Singhb, Navneet kaurc

aDAV College, Sector 10, Chandigarh (India)-160010 bDepartment of Chemistry, Indian Institute Technology Ropar, Punjab, 140001, India.cDepartment of Chemistry, Panjab University Chandigarh 160014, IndiadDepartment of Chemical Sciences,Indian Institute of Science Education and Research, Sector

81, Manauli PO, S.A.S. Nagar, Mohali, Punjab, 140306, India

*Corresponding author (Aman KK Bhasin); E-mail: akkb8785@gmail.com; Tel: +91-

8557895390.

Electronic Supplementary Material (ESI) for New Journal of Chemistry.This journal is © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2020

2

Contents

Figure S1.1H NMR spectrum of ligand L in dmso-d6.

Figure S2.13C NMR spectrum of ligand L in dmso-d6.

Figure S3.Mass spectrum of ligand L determined by electrospray ionization technique (ESI-MS).

Figure S4. Competitive binding experiment between Cu2+and organic nanoparticles A1 in the presence of competing metal ion pool.

Figure S5. Stern-volmer plot for determination of association constant (Ka) between Cu2+and organic nanoparticles, A1.

Figure S6. Job plot to determine the stoichiometry of the chemical coordination between the host ligand A1 and guest metal ion Cu2+.

Figure S7.11H NMR titration of A1 in presence and absence of Cu2+ in dmso-d6 (Ha and Hb denote hydroxyl proton and iminic hydrogen of A1, respectively)

Figure S7.21H NMR titration of A1 in presence of Cu2+and azamethiphos in dmso-d6 (Ha and Hb denote hydroxyl proton and iminic hydrogen of A1, respectively)

Figure S8. Benesi-Hildebrand plot to determine the binding constant between Cu2+.A1 with azamethiphos where F0 and F denote the fluorescence emission intensity of the copper-bound receptor complex Cu2+.A1 in the absence and presence of azamethiphos (analyte), respectively.[G] represents the molar concentration of azamethiphos.

Figure S9. Job plot to determine the stoichiometry of the binding interaction between the host complex Cu2+.A1 and azamethiphos (analyte). [H] and [G] represent the molar concentration of the host complex Cu2+.A1 and azamethiphos, respectively

Figure S10. Competitive binding experiment of copper.ligand ensemble (Cu2+.A1) towards azamethiphos in the presence of select organophosphate pesticides

Figure S11. 31P NMR spectrum of azamethiphos in the presence and absence of copper-ligand ensemble, Cu2+.A1

Figure S12. Fluorescence profile of Cu2+.A1 (50µM ; λem = 430nm) in presence of a library of select anions (50 µM) in aqueous medium

Figure S13. Fluorescence titration studies of azamethiphos (λem= 330 nm) with Cu2+ (0- 50 µM)

Figure S14. Fluorescence profile of azamethiphos (λem = 330 nm) in the presence of (i) Cu2+ (ii) ligand (A1) and (iii) ligand-copper ensemble (A1.Cu2+)

3

Figure S15. Cyclical fluctuations in fluorescence intensity (λem = 430 nm) of title ligand A1 upon sequential dosage of azamethiphos (100 - 40 µM) and Cu2+ (50-10 µM) in an alternate pattern

Figure S16. Fluorescence studies in deionized water and select real water samples (tap water, rain water and well water) of (a) A1 (λem = 430 nm) upon spiking with Cu2+ (10, 20, 30, 40 and 50 µM) and (b) A1.Cu2+ (λem = 440 nm) upon spiking with azamethiphos (10, 20, 30, 40 and 50 µM)

Figure S17. Fully labeled molecular structure of ligand L

Table S1. Crystal data and structure refinement for ligand L

Table S2. Selected bond lengths (Å) of L

Table S3. Selected bond angles (Aº) of L

4

16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 ppm

0.0000

2.3876

2.3902

5.0064

6.0871

6.0898

6.8171

6.8396

6.9925

7.0012

7.0048

7.0137

7.0250

7.0309

7.2655

7.2752

7.2784

7.2875

7.2908

7.5087

7.5313

9.1165

14.7626

3.19

2.11

1.00

1.03

1.98

1.29

1.07

1.03

1.02

Current Data ParametersNAME Jul07-2016EXPNO 500PROCNO 1

F2 - Acquisition ParametersDate_ 20160708Time 11.00INSTRUM spectPROBHD 5 mm PABBO BB-PULPROG zg30TD 65536SOLVENT CDCl3NS 8DS 2SWH 12019.230 HzFIDRES 0.183399 HzAQ 2.7263477 secRG 406DW 41.600 usecDE 6.00 usecTE 297.8 KD1 1.00000000 secTD0 1

======== CHANNEL f1 ========NUC1 1HP1 10.90 usecPL1 -3.00 dBSFO1 400.1324710 MHz

F2 - Processing parametersSI 32768SF 400.1300074 MHzWDW EMSSB 0LB 0.30 HzGB 0PC 1.00

AKB-CO-THIOPBRUKERAVANCE II 400 NMRSpectrometerSAIFPanjab UniversityChandigarh

manishkumarmanu1986@gmail.com

Figure S1. 1H NMR spectrum of ligand L in dmso-d6 (Ha and Hb denote hydroxyl and iminic protons, respectively).31

-20-100102030405060708090100110120130140150160170180190200210220f1 (ppm)

-0.01

0.00

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0.10

0.1118.9

3

52.7

5

104.

9210

8.72

109.

18

117.

43

126.

9012

7.34

127.

8113

1.21

140.

07

154.

8315

5.42

159.

9116

1.00

171.

92

Figure S2.13C NMR spectrum of ligand L in dmso-d6.

Ha

Hb

5

WATERS, Q-TOF MICROMASS (ESI-MS) SAIF/CIL,PANJAB UNIVERSITY,CHANDIGARH

m/z60 80 100 120 140 160 180 200 220 240 260 280 300 320 340 360 380 400 420 440 460 480 500 520

%

0

100AMAN AKB-CO-Thiop 6 (0.164) Cm (3:13-14:29) TOF MS ES+

7.70e3322.31047703

300.35961470

97.3748464

323.33261147

324.3213415 423.2388

253

Figure S3. Mass spectrum of ligand L via electrospray ionization technique (positive mode)

Figure S4. Competitive binding experiment of title ligand A1 with Cu2+ in the presence of competing select metal ions.

6

0 4 8 12 16 20 24 28 32 36 40 44 480.8

1.0

1.2

1.4

1.6

1.8

2.0

2.2

2.4

2.6

I 0/I

[Cu2+] M

R2 = 0.9777

Figure S5. Stern-Volmer plot for determination of association constant (Ka) between Cu2+ and organic

nanoparticles A1

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.10.00

6.40x10-5

1.28x10-4

1.92x10-4

2.56x10-4

3.20x10-4

3.84x10-4

4.48x10-4

[HG

]

[H]/[H][G] Figure S6. Job plot to determine the stoichiometry of the chemical coordination between the host ligand A1 and guest metal ion Cu2+.

7

Ha Hb

Figure S7.1 1H NMR titration of A1 in presence and absence of Cu2+ in dmso-d6 (Ha and Hb denote hydroxyl proton and iminic hydrogen of A1, respectively)

Figure S7.2 1H NMR titration of A1 in presence of Cu2+and azamethiphos in dmso-d6 (Ha and Hb denote hydroxyl proton and iminic hydrogen of A1, respectively)

Copper-free receptor ligand A1Hb

Ha

Copper-bound receptor ligand A1

Ha Hb

8

0.00

5.50x104

1.10x105

1.65x105

2.20x105

2.75x105

0.0

2.0x10-3

4.0x10-3

6.0x10-3

8.0x10-3

1.0x10-2

1.2x10-2

1/[F

-F0]

1/[G] (M-1)

R2= 0.99864

Figure S8. Benesi-Hildebrand plot to determine the binding constant between Cu2+.A1 with azamethiphos where F0 and F denote the fluorescence emission intensity of the copper-bound receptor complex Cu2+.A1 in the absence and presence of azamethiphos (analyte), respectively.[G] represents the molar concentration of azamethiphos.

0.0 0.2 0.4 0.6 0.8 1.00.4

0.6

0.8

1.0

1.2

1.4

1.6

[HG

]

[H]/[H][G]

Figure S9. Job plot to determine the stoichiometry of the binding interaction between the host complex Cu2+.A1 and azamethiphos (analyte). [H] and [G] represent the molar concentration of the host complex Cu2+.A1 and azamethiphos, respectively

9

1

2

3

4

5

6

7

8

9

0 200 400 600 800 1000Intensity (a.u.)

A1+Cu+Azamethiphos

A1+Cu+Azamethiphos+Phosmet

A1+Cu+Azamethiphos+Fenitronthion

A1+Cu+Azamethiphos+Azinophos methyl

A1+Cu+Azamethiphos+Parathion methyl

A1+Cu+Azamethiphos+Parathion Solution

Ligand (A1)

A1+Cu

A1+Cu+Azamethiphos+Chlorpyrifos

Figure S10. Competitive binding experiment of copper:ligand ensemble (Cu2+.A1 ; λem = 440 nm) towards azamethiphos in the presence of select organophosphate pesticides

Figure S11. 31P NMR spectrum of azamethiphos in the presence and absence of copper-ligand ensemble, Cu2+.A1

10

0 100 200 300 400 500

Ligand (A1)A1+Cu

A1+Cu+Sulphide

A1+Cu+Sulphate

A1+Cu+Chloride

A1+Cu+Bromide

A1+Cu+Acetate

A1+Cu+Carbonate

A1+Cu+Nitrate

A1+Cu+Hydroxide

A1+Cu+Nitrite

A1+Cu+Phosphate

A1+Cu+Thiosulphate

A1+Cu+Persulphate

Intensity (a.u.)

Sodi

um A

nion

sA1+Cu+Sulphite

Figure S12. Fluorescence profile of Cu2+.A1 (50µM ; λem = 430nm) in presence of a library of select anions (50µM) in aqueous medium.

11

Figure S13. Fluorescence titration studies of azamethiphos (100 µM; λem = 330 nm) with Cu2+ (0-50 µM)

1 2 3 4

800

1000

1200

1400

1600

Azamethiphos+A1+Cu2+

Azamethiphos+Ligand(A1)

Azamethiphos+Cu2+

Inte

nsity

(a.u

.)

Azamethiphos

Figure S14. Fluorescence profile of azamethiphos (λem = 330 nm) in the presence of (i) Cu2+ (ii) ligand (A1) and (iii) ligand-copper ensemble (A1.Cu2+)

12

Figure S15. Cyclical fluctuations in fluorescence intensity of ligand A1(λem = 430 nm; 10µM) upon sequential dosage of azamethiphos (100 - 40 µM) and Cu2+ (50-20 µM) in an alternate pattern.

10 20 30 40 500

20

40

60

80

100

120

140

Reco

very

(%)

Concentration (M)

Deionised Water Tap Water Rain Water Well Water

10 20 30 40 500

20

40

60

80

100

Concentration (M)

Reco

very

(%)

(a)(b)

Figure S16. Fluorescence studies in deionized water and select real water samples (tap water, rain water and well water) of (a) A1 (λem = 430 nm) upon spiking with Cu2+ (10, 20, 30, 40 and 50 µM) and (b) A1.Cu2+ (λem = 440 nm) upon spiking with azamethiphos (10, 20, 30, 40 and 50 µM)

13

Figure S17. Fully labeled molecular structure of ligand L

Table S1. Crystal data and structure refinement for ligand L

Chemical formula C16H13NO3SFormula weight 299.33Temperature 296(2) KWavelength 0.71073 ÅCrystal system TriclinicSpace group P -1Unit cell dimensions a = 7.518(7) Å α = 70.671(10)°

b = 9.118(9) Å β = 71.668(11)°c = 11.293(11) Å γ = 78.323(11)°

Volume 689.2(11) Å3

Z 2Density (calculated) 1.442 g/cm3

Absorption coefficient 0.244 mm-1

F(000) 312

14

Theta range for data collection

1.98 to 25.16°

Index ranges -8<=h<=8, -10<=k<=10, -13<=l<=13

Reflections collected 8677Independent reflections 2461 [R(int) = 0.0180]Coverage of independent reflections

99.9%

Absorption correction multi-scanStructure solution technique

direct methods

Structure solution program SHELXS-97 (Sheldrick, 2008)Refinement method Full-matrix least-squares on F2

Refinement program SHELXL-97 (Sheldrick, 2008)Function minimized Σ w(Fo

2 - Fc2)2

Data / restraints / parameters

2461 / 0 / 192

Goodness-of-fit on F2 1.051Final R indices 2186 data; I >2σ (I)

all dataR1 = 0.0460, wR2 = 0.1408R1 = 0.0503, wR2 = 0.1461

Weighting scheme w=1/[σ2(Fo2)+(0.0917P)2+0.2923P]

where P=(Fo2+2Fc

2)/3Largest diff. peak and hole 0.652 and -0.494 eÅ-3

Table S2. Bond lengths (Å) of L

S1-C8 1.718(3) S1-C11 1.716(3)O1-C4 1.370(2) O1-C12 1.394(2)O2-C12 1.210(3) O3-C16 1.256(3)O3-H4 0.82 N1-C6 1.301(3)N1-C7 1.476(2) C1-C2 1.498(3)C1-H8 0.96 C1-H9 0.96C1-H1 0.96 C2-C13 1.356(3)C2-C3 1.437(3) C3-C4 1.385(3)C3-C14 1.431(3) C4-C5 1.418(3)C5-C6 1.413(3) C5-C16 1.457(3)C6-H10 0.93 C7-C8 1.498(3)C7-H11 0.97 C7-H12 0.97C8-C9 1.381(3) C9-C10 1.406(4)C9-H13 0.93 C10-C11 1.332(4)C10-H2 0.93 C11-H3 0.93C12-C13 1.428(3) C13-H5 0.93C14-C15 1.353(3) C14-H6 0.93

15

C15-C16 1.441(3) C15-H7 0.93

Table S3. Bond angles (º) of L

C8-S1-C11 92.10(13) C4-O1-C12 121.98(14)C16-O3-H4 109.5 C6-N1-C7 122.80(16)C2-C1-H8 109.5 C2-C1-H9 109.5H8-C1-H9 109.5 C2-C1-H1 109.5H8-C1-H1 109.5 H9-C1-H1 109.5C13-C2-C3 119.12(17) C13-C2-C1 120.65(18)C3-C2-C1 120.23(18) C4-C3-C14 116.83(18)C4-C3-C2 118.65(18) C14-C3-C2 124.51(17)O1-C4-C3 121.11(17) O1-C4-C5 115.37(15)C3-C4-C5 123.53(17) C6-C5-C4 120.25(17)C6-C5-C16 121.06(17) C4-C5-C16 118.68(16)N1-C6-C5 124.29(17) N1-C6-H10 117.9C5-C6-H10 117.9 N1-C7-C8 112.65(16)N1-C7-H11 109.1 C8-C7-H11 109.1N1-C7-H12 109.1 C8-C7-H12 109.1H11-C7-H12 107.8 C9-C8-C7 126.54(19)C9-C8-S1 110.08(16) C7-C8-S1 123.37(16)C8-C9-C10 112.5(2) C8-C9-H13 123.7C10-C9-H13 123.7 C11-C10-C9 113.8(2)C11-C10-H2 123.1 C9-C10-H2 123.1C10-C11-S1 111.5(2) C10-C11-H3 124.2S1-C11-H3 124.3 O2-C12-O1 115.57(17)O2-C12-C13 127.85(18) O1-C12-C13 116.58(17)C2-C13-C12 122.53(18) C2-C13-H5 118.7C12-C13-H5 118.7 C15-C14-C3 122.29(17)C15-C14-H6 118.9 C3-C14-H6 118.9C14-C15-C16 122.17(18) C14-C15-H7 118.9C16-C15-H7 118.9 O3-C16-C15 122.47(18)O3-C16-C5 121.03(17) C15-C16-C5 116.49(18)