Supplementary Information

Ring-opening hydrolysis of spiro-epoxyoxindoles using reusable sulfonic acid functionalized nitrogen rich carbon catalystParth Patel,a,b Raj Kumar Tak,a,c Bhavesh Parmar,a,c Shilpa Dabas,a Brijesh Patel,a,c Eringathodi

Suresh,c,d Noor-ul H. Khana,c* Saravanan Subramaniana,c*

aInorganic Materials and Catalysis Division, CSIR-Central Salt & Marine Chemicals Research Institute, G. B. Marg,

Bhavnagar-364002, Gujarat, India

bCharotar University of Science and Technology, Changa, Anand-388421, Gujarat, India

cAcademy of Scientific and Innovative Research (AcSIR), Ghaziabad-201002, India

dAnalytical and Environmental Science Division and Centralized Instrument Facility, CSIR-Central Salt & Marine

Chemicals Research Institute, G. B. Marg, Bhavnagar-364002, Gujarat (India)

E-mail: khan251293@yahoo.in; saravanans@csmcri.res.in

X-ray Crystallography

The crystallographic data and refinement for 2a, 2b, 2c, 2e and 2g are provided in Table

S1. Crystal of suitable size was selected from the mother liquor and immersed in

paratone oil and then mounted for data collection. Single crystal X-ray data was

collected using a Bruker D8 QUEST (PHOTON) diffractometer. The linear absorption

coefficients, scattering factors for the atoms, and the anomalous dispersion

corrections were obtained from International Tables for X-ray Crystallography. The

data integration and reduction were processed using SAINTPLUS software.S1 An

empirical absorption correction was applied to the collected reflections with SADABS

using XPREP.S2 The structure was solved by the direct method using SHELXTLS3 and was

refined on F2 by a full-matrix least-squares technique using the SHELXL-2014S4 program

package. Non-hydrogen atoms were refined anisotropically and the hydrogen atoms

Electronic Supplementary Material (ESI) for RSC Advances.This journal is © The Royal Society of Chemistry 2021

attached to the organic moiety were stereochemically fixed. CCDC numbers 1961234-

1961238 corresponds to all the compounds reported in this manuscript and this data

can be obtained free of charge from The Cambridge Crystallographic Data Center via

www.ccdc.cam.ac.uk/data_request/cif

Table S1. Crystal Data and Refinement Parameters for 2a, 2b, 2c, 2e, and 2g.

Identification code 2a 2b 2c 2e 2g

Chemical formula C128H120N8O24 C10H11NO3 C12H13NO3 C17H17NO4 ClC16H14NO3

Formula weight (g/mol) 2154.31 193.20 219.23 299.31 303.73

Crystal Color Colorless Colorless Colorless Light Yellow ColorlessCrystal Size (mm)

0.44 x 0.08 x 0.05

0.29 x 0.24 x 0.22

0.33 x 0.12 x 0.04

0.60 x 0.40 x 0.10

0.36 x 0.07 x 0.06

Temperature (K) 301(2) 122(2) 150(2) 305(2) 301(2)

Crystal System Orthorhombic Monoclinic Orthorhombic Monoclinic OrthorhombicSpace Group P 21 21 21 P 21/n P 21 21 21 P c F d d 2a(Å ) 5.1638(3) 8.3175(11) 5.8505(12) 8.4593(5) 62.210(8)b(Å ) 19.3060(12) 10.2481(16) 11.594(2) 5.8691(4) 17.713(2)c(Å ) 27.209(2) 10.9658(17) 16.205(3) 30.718(2) 5.2259(7)(º) 90 90 90 90 90(º) 90 98.059(5) 90 97.420(2) 90(º) 90 90 90 90 90Z 1 4 4 4 16V(Å3) 2712.5(3) 925.5(2) 1099.2(4) 1512.33(18) 5758.6(13)Density (Mg/m3) 1.319 1.387 1.325 1.315 1.401

μ(mm-1) 0.092 0.103 0.096 0.094 0.274F(000) 1136 408 464 632 194Reflections Collected 20795 11988 5494 22546 18150

Independent Reflections 6671 2254 1934 5901 9343

Rint 0.1001 0.0426 0.0510 0.0409 0.0835Number of parameters 369 160 175 469 194

GOF on F2 0.994 1.135 1.114 1.043 1.009Final R1/wR2 (I ≥2(I)

0.0621/0.1019 0.0604/0.1858 0.0767/0.1348 0.0511/0.1309 0.0635/0.1328

Weighted R1/wR2 (all data)

0.2041/0.1476 0.0725/0.1953 0.0888/0.1387 0.0661/0.1430 0.1448/0.1730

CCDC number 1961235 1961236 1961234 1961237 1961238

Figure S1. XPS Deconvoluted Spectrum of N 1S.

Figure S2. Powder XRD pattern of Cal-CB6 and SO3H@N-C/CB6.

Figure S3. SEM image of SO3H@N-C/CB6.

1H & 13C NMR analysis of hydrolysis products of spiro epoxyoxindoles

N

O

O

BnN

HO

O

Bn

OH

1a 2a

2a: 1H NMR (600 MHz, CDCl3), δ 7.41 (d, J = 7.5 Hz, 1H), 7.28 – 7.20 (m, 5H), 7.17 (t, J = 7.5 Hz,

1H), 7.02 (t, J = 7.6 Hz, 1H), 6.67 (d, J = 7.9 Hz, 1H), 4.91 (d, J = 15.9 Hz, 1H), 4.73 (d, J = 15.7

Hz, 1H), 3.89 (s, 2H). 13C NMR (151 MHz, CDCl3 ) δ 177.98, 142.59, 135.26, 129.90, 128.90,

127.75, 127.19, 124.59, 123.46, 109.70, 76.23, 66.92, 43.78.

N

O

O

MeN

HO

O

Me

OH

1b 2b

2b: 1H NMR (600 MHz, CDCl3), δ 7.39 (d, J = 7.2 Hz, 1H), 7.35 (t, J = 7.9 Hz, 1H), 7.11 (t, J = 7.5

Hz, 1H), 6.85 (d, J = 7.8 Hz, 1H), 3.86 – 3.77 (m, 2H), 3.19 (s, 3H), 1.67 (s, 1H). 13C NMR (151

MHz, CDCl3) δ 177.66, 143.66, 130.32, 127.57, 124.42, 123.52, 108.76, 75.42, 66.92, 26.29.

N

O

ON

HO

OOH

1c 2c

2c : 1H NMR (600 MHz, CDCl3) δ 7.40 (d, J = 7.3 Hz, 1H), 7.30 (t, J = 7.5 Hz, 1H), 7.09 (t, J = 7.5

Hz, 1H), 6.83 (d, J = 7.9 Hz, 1H), 5.80 (ddd, J = 21.6, 10.3, 5.3 Hz, 1H), 5.25 – 5.18 (m, 2H), 4.36

– 4.32 (m, 1H), 4.24 (dd, J = 16.5, 4.9 Hz, 1H), 3.89 – 3.79 (m, 2H), 3.17 (s, 1H). 13C NMR (151

MHz, CDCl3) δ 177.49, 142.82, 130.90, 130.14, 127.72, 124.50, 123.45, 117.94, 109.64, 75.57,

67.02, 42.35.

N

O

O

BnN

HO

O

Bn

OHH3C H3C

1d 2d

2d : 1H NMR (600 MHz, CDCl3) δ 7.31 – 7.27 (m, 2H), 7.26 – 7.22 (m, 4H), 7.01 (d, J = 7.9 Hz,

1H), 6.59 (d, J = 8.0 Hz, 1H), 4.96 – 4.72 (m, 2H), 3.88 (dt, J = 21.2, 11.4 Hz, 2H), 3.16 – 3.00

(m, 1H), 2.29 (s, 3H). 13C NMR (151 MHz, CDCl3) δ 177.78, 140.36, 135.31, 133.25, 130.44,

128.94, 127.82, 127.21, 125.25, 109.61, 75.59, 67.09, 43.79, 21.09.

N

O

O

BnN

HO

O

Bn

OHMeO MeO

1e 2e

2e : 1H NMR (600 MHz,CDCl3) δ 7.34 – 7.29 (m, 2H), 7.27 (d, J = 5.9 Hz, 4H), 7.02 (t, J = 2.0 Hz,

1H), 6.77 – 6.73 (m, 1H), 6.62 (d, J = 8.6 Hz, 1H), 4.93 (d, J = 15.7 Hz, 1H), 4.80 (d, J = 15.7 Hz,

1H), 3.88 (d, J = 13.8 Hz, 2H), 3.76 (s, 3H), 2.90 (s, 1H). 13C NMR (151 MHz, CDCl3) δ 129.04,

127.95, 127.28, 111.48, 110.52, 67.21, 55.97, 43.93.

N

O

O

BnN

HO

O

Bn

OH

1f 2f

F F

2f : 1H NMR (600 MHz,CDCl3) δ 7.30 – 7.21 (m, 5H), 7.17 (dd, J = 7.9, 2.3 Hz, 1H), 6.88 (td, J =

8.6, 2.4 Hz, 1H), 6.60 (dd, J = 8.6, 4.0 Hz, 1H), 4.91 (d, J = 15.7 Hz, 1H), 4.78 (s, 1H), 4.75 (d, J =

15.6 Hz, 1H), 3.89 (s, 2H), 3.54 (s, 1H). 13C NMR (151 MHz, CDCl3) δ 177.73, 160.45, 138.42,

134.87, 129.78, 129.73, 129.03, 127.97, 127.16, 116.36, 116.21, 112.98, 112.81, 110.53,

110.47, 76.22, 66.93, 43.97.

N

O

O

BnN

HO

O

Bn

OH

1g 2g

Cl Cl

2g : 1H NMR (600 MHz,CDCl3 ) δ 7.35 – 7.26 (m, 4H), 7.25 (d, J = 7.3 Hz, 3H), 7.05 (d, J = 8.3 Hz,

1H), 6.72 (s, 1H), 4.91 (s, 1H), 4.78 (d, J = 15.6 Hz, 1H), 3.85 (d, J = 3.3 Hz, 2H), 2.68 (s, 1H). 13C

NMR (151 MHz,CDCl3) δ 129.14, 128.14, 127.17, 125.48, 123.45, 110.49, 66.87, 43.90.

N

O

O

MeN

HO

O

Me

OH

1j 2j

Me Me

2j : 1H NMR (200 MHz, CDCl3) δ 7.37 – 7.08 (m, 2H), 6.76 (d, J = 7.9 Hz, 1H), 4.43 (s, 1H), 3.85

(s, 2H), 3.19 (s, 3H), 2.36 (s, 3H). 13C NMR (50 MHz, CDCl3) δ 177.61, 141.13, 133.11, 130.30,

127.75, 125.18, 108.40, 66.90, 26.24, 21.05.

N

O

O

BnN

O

O

Bn

OH

1k 2k

2k : 1H NMR (600 MHz,CDCl3 ) δ 7.39 (d, J = 7.2 Hz, 1H), 7.32 – 7.23 (m, 6H), 7.08 (t, J = 7.5 Hz,

1H), 6.75 (d, J = 7.9 Hz, 1H), 4.93 (s, 2H), 3.91 (q, J = 11.4 Hz, 2H), 3.13 (s, 3H), 2.69 (s, 1H). 13C

NMR (151 MHz,CDCl3) δ 175.04, 143.45, 135.50, 130.25, 128.96, 127.85, 127.27, 125.20,

125.02, 123.27, 109.76, 82.74, 66.85, 53.49, 43.90.

2.22.42.62.83.03.23.43.63.84.04.24.44.64.85.05.25.45.65.86.06.26.46.66.87.07.27.47.67.8f1 (ppm)

-0.5

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

5.5

6.0

6.5

1.89

0.84

0.92

0.70

0.86

0.92

4.76

0.87

3.89

4.71

4.74

4.90

4.92

6.66

6.68

7.00

7.02

7.03

7.16

7.17

7.18

7.20

7.22

7.23

7.25

7.25

7.26

7.28

7.40

7.42

N

O

OHOH

Figure S4. 1H NMR of 2a.

0102030405060708090100110120130140150160170180190f1 (ppm)

-0.02

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16

0.18

0.20

0.22

0.24

0.26

0.2843.7

8

66.9

2

76.2

3

109.

70

123.

4612

4.59

127.

1912

7.75

128.

9012

9.90

135.

2614

2.59

177.

98

Figure S5. 13C NMR of 2a.

1.01.52.02.53.03.54.04.55.05.56.06.57.07.5f1 (ppm)

0

1

2

3

4

5

6

7

8

9

101.

56

3.00

1.96

1.03

1.00

1.88

1.67

3.19

3.78

3.80

3.80

3.82

3.84

6.85

6.86

7.10

7.11

7.12

7.34

7.35

7.37

7.38

7.40

N

CH3

O

OHOH

Figure S6. 1H NMR of 2b.

0102030405060708090100110120130140150160170180190200f1 (ppm)

0.000

0.005

0.010

0.015

0.020

0.025

0.030

0.035

26.2

9

66.9

2

75.4

2

108.

76

123.

5212

4.42

127.

5713

0.32

143.

66

177.

66

N

CH3

O

OHOH

Figure S7. 13C NMR of 2b.

1.52.02.53.03.54.04.55.05.56.06.57.07.58.08.59.0f1 (ppm)

-0.5

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

5.5

6.0

0.92

2.05

1.08

1.14

2.06

1.01

1.00

1.01

1.01

1.00

3.17

3.80

3.82

3.85

3.87

4.22

4.23

4.25

4.26

4.32

4.33

4.33

4.35

4.36

5.20

5.21

5.23

5.77

5.78

5.79

5.80

5.81

5.82

5.83

5.84

6.83

6.84

7.08

7.09

7.10

7.25

7.29

7.30

7.31

7.40

7.41

N

O

OHOH

CH2

Figure S8. 1H NMR of 2c.

2030405060708090100110120130140150160170180190f1 (ppm)

-0.004

-0.002

0.000

0.002

0.004

0.006

0.008

0.010

0.012

0.014

0.016

0.018

0.020

0.022

0.024

0.026

0.028

0.030

0.032

0.034

0.036

0.038

0.040

42.3

5

67.0

2

75.5

7

109.

64

117.

9412

3.45

124.

5012

7.72

130.

1413

0.90

142.

82

177.

49

N

O

OHOH

CH2

Figure S9. 13C NMR of 2c.

2.22.42.62.83.03.23.43.63.84.04.24.44.64.85.05.25.45.65.86.06.26.46.66.87.07.27.47.67.8f1 (ppm)

-0.5

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

5.5

6.0

6.5

7.0

7.5

8.0

3.03

0.96

2.04

2.04

1.00

1.01

4.10

2.03

2.29

3.09

3.10

3.13

3.84

3.86

3.88

3.89

3.91

4.76

4.79

4.90

4.93

6.59

6.60

7.00

7.02

7.22

7.24

7.25

7.28

7.29

7.30

N

O

CH3

OHOH

Figure S10. 1H NMR of 2d.

0102030405060708090100110120130140150160170180190f1 (ppm)

-0.005

0.000

0.005

0.010

0.015

0.020

0.025

0.030

0.035

0.040

0.045

0.050

0.055

0.06021.0

9

43.7

9

67.0

9

75.5

9

109.

61

125.

2512

7.21

127.

8212

8.94

130.

4413

3.25

135.

3114

0.36

177.

78

N

O

CH3

OHOH

Figure S11. 13C NMR of 2d.

2.42.62.83.03.23.43.63.84.04.24.44.64.85.05.25.45.65.86.06.26.46.66.87.07.27.47.6f1 (ppm)

-0.2

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

2.2

2.4

2.6

2.8

3.0

3.2

1.02

3.10

2.17

1.02

1.05

1.02

0.98

1.00

4.11

2.16

2.90

3.76

3.85

3.86

3.89

3.91

4.79

4.81

4.92

4.95

6.62

6.63

6.75

6.76

6.76

7.02

7.02

7.02

7.26

7.27

7.30

7.32

7.33

N

O

OHOHO

CH3

Figure S12. 1H NMR of 2e.

2030405060708090100110120130140150160170180f1 (ppm)

0.000

0.005

0.010

0.015

0.020

0.025

0.030

0.035

0.040

43.9

3

55.9

7

67.2

1

110.

5211

1.48

127.

2812

7.95

129.

04

N

O

OHOHO

CH3

Figure S13. 13C NMR of 2e.

2.22.42.62.83.03.23.43.63.84.04.24.44.64.85.05.25.45.65.86.06.26.46.66.87.07.27.47.67.88.08.2f1 (ppm)

-0.5

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

5.5

6.0

6.5

7.0

7.5

8.0

8.5

1.00

2.14

1.15

0.92

1.07

1.05

1.05

1.02

5.24

3.54

3.89

4.74

4.76

4.78

4.90

4.93

6.58

6.59

6.60

6.61

6.87

6.87

6.88

6.89

6.90

6.90

7.16

7.16

7.17

7.18

7.22

7.23

7.24

7.25

7.27

7.29

7.30

N

O

OHOHF

Figure S14. 1H NMR of 2f.

0102030405060708090100110120130140150160170180f1 (ppm)

0.00

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.0943.9

7

66.9

3

76.2

2

110.

4711

0.53

112.

8111

2.98

116.

2111

6.36

127.

1612

7.97

129.

0312

9.73

129.

7813

4.87

138.

42

158.

8416

0.45

177.

73

N

O

OHOHF

Figure S15. 13C NMR of 2f.

2.53.03.54.04.55.05.56.06.57.07.58.08.5f1 (ppm)

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

0.95

2.01

0.99

1.00

0.96

0.98

3.19

4.08

2.68

3.84

3.85

4.76

4.79

4.91

6.72

7.04

7.06

7.25

7.26

7.31

7.32

7.33

N

OH

O

Bn

OH

Cl

Figure S16. 1H NMR of 2g.

0102030405060708090100110120130140150160170f1 (ppm)

-0.002

-0.001

0.000

0.001

0.002

0.003

0.004

0.005

0.006

0.007

0.008

0.009

0.010

0.011

0.012

0.013

0.014

0.015

0.016

0.017

0.018

0.019

0.020

0.021

0.022

0.023

43.9

0

66.8

7

110.

49

123.

4512

5.48

127.

1712

8.14

129.

14

N

OH

O

Bn

OH

Cl

Figure S17. 13C NMR of 2g.

2.02.53.03.54.04.55.05.56.06.57.07.58.08.59.09.5f1 (ppm)

-5.0×107

0.0

5.0×107

1.0×108

1.5×108

2.0×108

2.5×108

3.0×108

3.5×108

4.0×108

4.5×108

5.0×108

5.5×108

6.0×108

6.5×108

7.0×108

7.5×108

3.00

3.13

2.02

0.96

0.98

2.04

2.36

3.19

3.85

4.43

6.74

6.78

7.15

7.19

7.26

7.29

N

CH3

O

OHOHCH3

Figure S18. 1H NMR of 2j.

102030405060708090100110120130140150160170180190200210f1 (ppm)

-1.00×108

0.00

1.00×108

2.00×108

3.00×108

4.00×108

5.00×108

6.00×108

7.00×108

8.00×108

9.00×108

1.00×109

1.10×109

1.20×109

21.0

5

26.2

4

66.9

0

75.6

5 CD

Cl3

108.

40

125.

1812

7.75

130.

3013

3.11

141.

13

177.

61N

CH3

O

OHOHCH3

Figure S19. 13C NMR of 2j.

0.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.08.5f1 (ppm)

-0.5

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

5.5

6.0

6.5

7.0

7.5

8.0

8.5

0.90

3.00

2.00

2.05

0.97

1.00

6.04

1.00

2.69

3.13

3.88

3.90

3.92

3.94

4.90

4.93

4.96

6.74

6.75

7.07

7.08

7.10

7.23

7.24

7.25

7.26

7.26

7.28

7.29

7.30

7.39

7.40

N

OOH

O

CH3

Figure S20. 1H NMR of 2k.

102030405060708090100110120130140150160170180f1 (ppm)

-0.02

-0.01

0.00

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0.10

0.11

0.12

0.13

0.14

0.15

0.16

0.17

0.18

0.19

0.20

0.21

0.22

43.9

0

53.4

9

66.8

5

82.7

4

109.

7612

3.27

125.

0212

5.20

127.

2712

7.85

128.

9613

0.25

135.

5014

3.45

175.

04

N

O

OCH3

OH

Figure S21. 13C NMR of 2k.

References:

S1. SAINT+, 6.02 ed, Bruker AXS, Madison, WI, 1999.

S2. XPREP, 5.1 ed, Siemens Industrial Automation Inc., Madison, WI, 1995.

S3. Sheldrick, G. M. SHELXTL Reference Manual: Version 5.1; Bruker AXS, Madison, WI, 1997.

S4. Sheldrick, G. M. Crystal structure refinement with SHELXL. Acta Cryst. C 2015, 71, 3-8.