S1    

Covalent Assembly of Hetero-Sequenced Macrocycles and Molecular Cages through Orthogonal Dynamic Covalent

Chemistry (ODCC)

Kenji D. Okochi, Gun Su Han, Ian M. Aldridge, Yuliang Liu, Wei Zhang*

Department of Chemistry and Biochemistry, University of Colorado Boulder, CO 80309, USA

Supporting Information

List of Contents

1) Materials and Synthetic Methods S2 2) Experimental Procedures S2 – S7 3) GPC data S8-S9 4) MALDI-MS spectrum S10 5) NMR data S11 – S25 6) References S26

S2    

1) Materials and Synthetic Methods

Reagents and solvents were purchased from commercial suppliers and used without further purification, unless otherwise indicated. Ether, tetrahydrofuran, toluene, CH2Cl2 and DMF are purified by MBRAUN solvent purification systems. 9-hexadecyl-9H-carbazole,1 9-hexadecyl-3,6-diiodo-9H-carbazole,1 9-butyl-9H-carbazole-3,6-dicarbaldehyde,2 1,3,5-tri(4-formylphenyl)benzene,3 1,3,5-tri(4-aminophenyl)benzene,4 9-hexadecyl-6-iodo-9H-carbazole-3-carbaldehyde,5 and 9-octyl-9H-carbazole-3,6-diamine6 were prepared as previously described in the literature. All reactions were conducted in oven dried glassware. Unless otherwise specified, solvents were evaporated using a rotary evaporator after workup. Unless otherwise specified, the purity of the compounds was ≥ 95 % based on 1H NMR spectral integration. Flash column chromatography was performed by using a 100-150 times weight excess of flash silica gel 32-63 µm from Dynamic Absorbents Inc. Fractions were analyzed by TLC using TLC silica gel F254 250 µm precoated-plates from Dynamic Absorbents Inc. Analytical gel permeation chromatography (GPC) was performed using a Viscotek GPCmaxTM, a Viscotek Model 3580 Differential Refractive Index (RI) Detector, a Viscotek Model 3210 UV/VIS Detector and a set of two Viscotek Viscogel columns (7.8 × 30 cm, l- MBLMW-3078, and l-MBMMW-3078 columns) with THF as the eluent at 30 °C. The analytical GPC was calibrated using monodisperse polystyrene standards. MALDI Mass spectra were obtained on the Voyager-DE™ STR Biospectrometry Workstation using sinapic acid as the matrix. 1H NMR spectra were taken on Bruker 300, Inova 400 and Inova 500 spectrometers. 13C NMR spectra were obtained on Bruker 300 and Inova 400 spectrometers. gHSQC and gHMBC spectra were taken on Inova 500 spectrometer. gHSQC and gHMBC for compounds 13 and 14 were acquired in C6D6 at 60°C. All others were acquired in CDCl3 at room temperature. C6D6 (7.15 ppm), and CHCl3 (7.26 ppm) were used as internal references in 1H NMR, and C6D6 (127.88 ppm) and CHCl3 (77.23 ppm) for 13C NMR. 1H NMR data were reported in order: chemical shift, multiplicity (s, singlet; d, doublet; t, triplet; q, quartet; m, multiplet), number of protons, coupling constants (J, Hz).

2) Experimental Procedures

9-Hexadecyl-6-vinyl-9H-carbazole-3-carbaldehyde (3): The procedure reported by Butler and Denmark was followed.7 9-Hexadecyl-6-iodo-9H-carbazole-3-carbaldehyde (267 mg, 0.49 mmol), Pd2dba3 (22 mg, 0.024 mmol), TBAF (1.0 mL, 1.0 mmol), D4

V (2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane , 85 uL, 0.24 mmol) and THF (12.0 mL) were added to the reaction vessel under N2. The reaction was stirred at 80 °C for 4 h. The reaction mixture was cooled to room temperature, filtered through a short plug of silica gel with ether, and concentrated. The product was purified by flash column chromatography (gradient elution 5% EtOAc/hexanes to 10% EtOAc/hexanes) to yield a light yellow solid (165 mg, 76%). Physical

S3    

data for the product (3): 1H NMR (500 MHz, Chloroform-d) δ 10.10 (s, 1H), 8.62 (d, J = 1.1 Hz, 1H), 8.18 (s, 1H), 8.01 (dd, J = 8.5, 1.5 Hz, 1H), 7.63 (dd, J = 8.5, 1.5 Hz, 1H), 7.47 (d, J = 8.5 Hz, 1H), 7.40 (d, J = 8.5 Hz, 1H), 6.92 (dd, J = 17.5, 10.9 Hz, 1H), 5.81 (d, J = 17.6 Hz, 1H), 5.26 (d, J = 10.9 Hz, 1H), 4.32 (t, J = 7.3 Hz, 2H), 1.88 (p, J = 7.3 Hz, 2H), 1.45 – 1.10 (m, 26H), 0.87 (t, J = 6.9 Hz, 3H); 13C NMR (75 MHz, CDCl3) δ 191.92, 144.63, 141.15, 137.26, 130.55, 128.82, 127.39, 125.26, 124.32, 123.41, 123.31, 118.83, 112.31, 109.62, 109.33, 43.76, 32.14, 29.90, 29.88, 29.85, 29.80, 29.75, 29.67, 29.58, 29.56, 29.17, 27.45, 22.91, 14.35; HR MS (ESI): Calc’d for C31H43NO [M+] 446.3418; Found 446.3422.

9-Hexadecyl-3-nitro-9H-carbazole (10): The procedure reported by Zhang et al. was followed.8 9-Hexadecyl-9H-carbazole (9, 2.00 g, 5.11 mmol) was dissolved in 1,2-dichloroethane (14 mL) and the solution was cooled to 10 °C using cold water. HNO3 (0.34 mL, 5.62 mmol, 70%) was added drop-wise over the course of 30 minutes. The reaction was stirred at 10 °C for 30 minutes and then at 40 °C until the reaction was completed based on 1H NMR analysis (~24 h). The reaction mixture was diluted with CHCl3 (100 mL) and washed with H2O (100 mL). The water layer was extracted with CHCl3 until it became colorless. The combined organic layer was dried, and concentrated to yield crude product 10 (2.23 g). The product was used in the next step without further purification. Physical data for the product: 1H NMR (300 MHz, Chloroform-d) δ 9.01 (t, J = 2.5 Hz, 1H), 8.38 (dt, J = 9.1, 1.7 Hz, 1H), 8.15 (d, J = 7.8 Hz, 1H), 7.62 – 7.51 (m, 1H), 7.51 – 7.44 (m, 1H), 7.43 – 7.30 (m, 2H), 4.34 (t, J = 6.8 Hz, 2H), 1.89 (p, J = 7.3 Hz, 2H), 1.48 – 1.14 (m, 26H), 0.87 (t, 3H); 13C NMR (75 MHz, CDCl3) δ 143.72, 141.81, 140.74, 127.54, 123.04, 122.73, 121.81, 121.19, 120.91, 117.55, 109.88, 108.44, 43.83, 32.14, 29.90, 29.87, 29.84, 29.79, 29.74, 29.67, 29.58, 29.54, 29.12, 27.45, 22.91, 14.35; HR-MS (ESI): Calc’d for C28H40N2O2 [M+] 437.3168; Found 437.3163.

9-Hexadecyl-3-iodo-6-nitro-9H-carbazole (11): The above 9-hexadecyl-3-nitro-9H-carbazole (10, 2.23 g, 5.11 mmol) was dissolved in CHCl3 (30 mL). A solution of ICl (995 mg, 0.32 mL, 6.13 mmol) in acetonitrile (2.4 mL) was added to the reaction vessel with stirring. The reaction was heated at 40 °C for 2 h then cooled to room temperature. The solution was diluted with CHCl3 (100 mL), washed with aqueous solution of Na2S2O5, and NaHCO3 until it became neutral. The organic layer was dried and concentrated to yield a yellow solid (2.74 g). The product 11 was used in the next step without further purification. Physical data for the product 11: 1H NMR (500 MHz, Chloroform-d) δ 8.96 (d, J = 2.2 Hz, 1H), 8.47 (d, J = 1.6 Hz, 1H), 8.40 (dd, J = 9.1, 2.2 Hz, 1H), 7.81 (dd, J = 8.6, 1.6 Hz, 1H), 7.41 (d, J = 9.1 Hz, 1H), 7.26 (d, 1H),

S4    

4.31 (t, J = 7.3 Hz, 2H), 1.86 (p, J = 7.3 Hz, 2H), 1.40 – 1.15 (m, 26H), 0.87 (t, J = 6.9 Hz, 3H); 13C NMR (75 MHz, CDCl3) δ 143.55, 141.15, 141.01, 135.86, 130.08, 125.40, 122.38, 121.43, 117.73, 111.85, 108.76, 83.55, 43.95, 32.14, 29.90, 29.88, 29.84, 29.79, 29.72, 29.64, 29.58, 29.50, 29.07, 27.40, 22.92, 14.35; HR-MS (ESI): Calc’d for C28H39IN2O2 [M+] 563.2134; Found 563.2134.

9-Hexadecyl-6-iodo-9H-carbazol-3-amine (12): 9-Hexadecyl-3-iodo-6-nitro-9H-carbazole (11, 1.00 g, 1.78 mmol), SnCl2 (1.72 g, 8.9 mmol) and ethanol (20 mL) were added to a Schlenk tube and the mixture was heated at 95 °C for 15 h. The reaction mixture was cooled to room temperature, diluted with Et2O (50 mL). and washed with aqueous NaOH solution (17%, 70 mL). The aqueous layer was extracted once more with ether (50 mL) and the combined organic layers were dried, and concentrated. The residue was purified by flash column chromatography (gradient elution 20% EtOAc/hexanes→40% EtOAc/hexanes) to yield a tan solid (747 mg, 79%). Physical data for the product 12: 1H NMR (500 MHz, Chloroform-d) δ 8.28 (d, J = 1.7 Hz, 1H), 7.63 (dd, J = 8.6, 1.7 Hz, 1H), 7.34 (d, J = 2.2 Hz, 1H), 7.20 (d, J = 8.6 Hz, 1H), 7.12 (d, J = 8.6 Hz, 1H), 6.92 (dd, J = 8.6, 2.3 Hz, 1H), 4.19 (t, J = 7.2 Hz, 2H), 3.63 (s, 2H), 1.80 (p, J = 7.3 Hz, 2H), 1.26 (m, J = 27.2, 11.6 Hz, 26H), 0.88 (t, J = 6.9 Hz, 3H); 13C NMR (75 MHz, CDCl3) δ 140.15, 139.33, 135.22, 133.72, 129.36, 125.06, 122.49, 116.52, 110.88, 109.68, 106.35, 80.35, 43.40, 32.15, 29.92, 29.89, 29.86, 29.82, 29.78, 29.71, 29.59, 29.16, 27.48, 22.92, 14.36; HR MS (ESI): Calc’d for C28H41IN2 [M+] 533.2393; Found 533.2397.

9-Hexadecyl-6-vinyl-9H-carbazol-3-amine (1): The procedure reported by Butler and Denmark was followed.6 9-Hexadecyl-6-iodo-9H-carbazol-3-amine (12, 747 mg, 1.40 mmol), Pd2dba3 (64 mg, 0.07 mmol), TBAF (2.8 mL, 1.0 M in THF), D4

V (2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane, 0.24 mL, 0.70 mmol) and THF (10.5 mL) were added to the reaction vessel under N2. The reaction was stirred at 80 °C for 4 h. The reaction mixture was cooled to room temperature, filtered through a short plug of silica gel with ether, and concentrated. The product was purified by flash column chromatography (20% EtOAc/hexanes) to yield a brown solid. The product was further purified by recrystallizing in ethanol (460 mg, 76%). The dried, purified product was dissolved in methylene chloride and filtered using a syringe filter into a small vial for storage. Physical data for the product 1: 1H NMR (500 MHz, Chloroform-d) δ 8.00 (d, J = 1.4 Hz, 1H), 7.53 (dd, J = 8.5, 1.6 Hz, 1H), 7.42 (d, J = 2.2 Hz, 1H), 7.28 (d, J = 8.6 Hz, 1H), 7.20 (d, J = 8.5 Hz, 1H), 6.95 – 6.83 (m, 2H), 5.73 (d, J = 17.5 Hz, 1H), 5.16 (d, J = 11.3 Hz, 1H), 4.21 (t, J = 7.2 Hz, 2H), 3.63 (s, 2H), 1.82 (p, J = 7.3 Hz, 2H), 1.39 – 1.11 (m, 26H), 0.87 (t, J = 6.9 Hz, 3H); 13C NMR (75 MHz, CDCl3) δ 140.97, 139.23, 137.83, 135.61,

S5    

128.24, 123.95, 123.85, 122.64, 118.69, 115.80, 110.67, 109.59, 108.78, 106.44, 43.42, 32.15, 29.92, 29.90, 29.86, 29.83, 29.80, 29.73, 29.63, 29.59, 29.26, 27.51, 22.92, 14.36; HR MS (ESI): Calc’d for C30H44N2 [M+] 433.3583; Found 433.3583.

9-Hexadecyl-3,6-divinyl-9H-carbazole (5): The procedure reported by Butler and Denmark was followed.6 9-Hexadecyl-3,6-diiodo-9H-carbazole (1.19 mg, 1.85 mmol), D4

V (2,4,6,8-tetramethyl-2,4,6,8-tetravinyl-cyclotetrasiloxane , 0.63 mL, 1.84 mmol), TBAF (7.4 mL, 1.0 M in THF), Pd2dba3 (84 mg, 0.092 mmol), and THF (30 mL) were added to a Schlenk tube and the mixture was heated at 80 °C for 16 h. The mixture was diluted with ether, filtered through a short plug of silica gel, and concentrated. The product was purified by flash column chromatography using hexanes as the eluent to yield an off-white oil that solidified to a white solid upon standing (534 mg, 65%). Physical data for the product 5: 1H NMR (500 MHz, Chloroform-d) δ 8.12 (d, J = 1.5 Hz, 2H), 7.57 (dd, J = 8.5, 1.6 Hz, 2H), 7.33 (d, J = 8.5 Hz, 2H), 6.91 (dd, J = 17.6, 10.9 Hz, 2H), 5.78 (d, J = 17.5 Hz, 2H), 5.21 (d, J = 10.9 Hz, 2H), 4.27 (t, J = 7.2 Hz, 2H), 1.91 – 1.79 (m, 2H), 1.39 – 1.16 (m, 26H), 0.88 (t, J = 6.9 Hz, 3H); 13C NMR (101 MHz, CDCl3) δ 140.86, 137.65, 129.15, 124.29, 123.24, 118.65, 111.26, 109.03, 43.47, 32.16, 29.92, 29.90, 29.86, 29.82, 29.79, 29.70, 29.60, 29.21, 27.48, 22.93, 14.37; HR MS (ESI): Calc’d for C32H45N [M+] 444.3630, Found 444.3630.

Macrocycle 13: 9-Hexadecyl-6-vinyl-9H-carbazol-3-amine (1, 25 mg, 0.058 mmol) and terephthalaldehyde (2, 3.9 mg, 0.029 mmol), were dissolved in 1,2,4-trichlorobenzene (2.0 mL). A trifluoroacetic acid/methylene chloride (0.1 uL/0.1 mL) mixture was added drop-wise with stirring. The reaction was stirred at room temperature for 30 min and then exposed to vacuum for 30 min. Hoveyda-Grubbs 2nd generation catalyst (2.0 mg, 0.003 mmol) was added and the reaction was heated at 45 °C under argon for 24 h. The reaction mixture was then pipetted drop-wise into a centrifuge tube containing hexanes (35 mL) and a precipitate was formed. The mixture was centrifuged to separate the solids. The solids were washed with hexanes (2 x 10 mL), and collected by centrifugation each time. The product was further purified by passing through a short plug of silica gel using chloroform as eluent to yield a yellow solid (17 mg, 64%). Physical data for the product 13: 1H NMR (400 MHz, Benzene-d6) δ 8.55 (s, 4H), 8.37 (s, 4H), 8.21 (s, 4H), 8.04 (s, 8H), 7.69 (d, J = 8.5 Hz, 4H), 7.64 (dd, J = 8.5, 1.7 Hz, 4H), 7.48 (s, 4H), 7.16 (d, J = 8.5 Hz, 8H), 3.85 (t, J = 6.9 Hz, 8H), 1.79 – 1.49 (m, 8H), 1.35 – 1.08 (m, 104H), 0.88 – 0.80

S6    

(m, 12H); 13C NMR (100 MHz, C6D6) δ 155.2, 143.7, 140.8, 140.1, 139.0, 129.6, 128.8, 126.7, 124.7, 124.5, 124.0, 121.7, 118.4, 112.0, 108.9, 108.9, 43.1, 31.9, 29.6, 28.9, 27.1, 22.4, 22.6, 13.8; MS (MALDI): Calc’d for C132H172N8 [M+] 1869.37; Found 1869.08.

Macrocycle 14: 9-Hexadecyl-6-vinyl-9H-carbazol-3-amine (1, 25 mg, 0.058 mmol), 9-hexadecyl-3,6-divinyl-9H-carbazole (5, 9.0 mg, 0.020 mmol), and 9-butyl-9H-carbazole-3,6-dicarbaldehyde (4, 8.1 mg, 0.029 mmol) were dissolved in 1,2,4-trichlorobenzene (2.5 mL). A trifluoroacetic acid/methylene chloride solution (0.1 uL/0.1 mL) was added drop-wise with stirring. The reaction was stirred at room temperature for 30 min and then exposed to vacuum for 30 min. Hoveyda-Grubbs 2nd generation catalyst (3.6 mg, 0.0058 mmol) was added and the reaction was heated at 50 °C under argon for 48 h. The solvent was removed under high vacuum. The resulting solids were passed through a short plug of silica gel using EtOAc/chloroform (1:9, v/v) as eluent. The green product was further purified by recrystallizing in benzene (9.0 mg, 20%). Physical data for the product 14: 1H NMR (500 MHz, Benzene-d6) δ 8.99 (s, 2H), 8.68 (s, 2H), 8.60 – 8.49 (m, 4H), 8.44 (s, 2H), 8.42 (s, 2H), 7.90 (d, J = 8.5 Hz, 2H), 7.75 (d, J = 8.4 Hz, 2H), 7.65 (d, J = 8.3 Hz, 2H), 7.61 – 7.42 (m, 4H), 7.27 – 7.16 (m, 10H), 4.00 – 3.87 (m, 6H), 3.81 (t, J = 7.1 Hz, 2H), 1.79 – 1.65 (m, 10H), 1.49 – 1.12 (m, 78H), 0.88 (t, J = 6.8 Hz, 9H), 0.75 (t, J = 7.3 Hz, 3H); 13C NMR (125 MHz, C6D6) δ 155.9, 143.7, 142.4, 140.8, 140.5, 140.0, 129.9, 129.7, 129.7, 126.8, 126.8, 125.7, 125.3, 124.1, 124.0, 124.0, 123.9, 123.6, 123.0, 122.9, 119.0, 117.7, 111.0, 108.9, 108.9, 108.9, 108.9, 43.1, 42.7, 37.3, 31.8, 31.1, 30.2, 30.0, 29.5, 27.3, 26.3, 24.4, 22.3, 21.1, 20.6, 20.2; MS (MALDI): Calc’d for C106H138N6 [M+] 1495.10; Found 1495.79.

S7    

Cage 16: 9-Hexadecyl-6-vinyl-9H-carbazol-3-amine (1, 25 mg, 0.058 mmol), tri-1,3,5-(4-formylphenyl)benzene (7, 7.5 mg, 0.019 mmol) were dissolved in 1,2,4-trichlorobenzene (2.5 mL). A trifluoroacetic acid/methylene chloride solution (0.1 uL/0.1 mL) was added drop-wise with stirring. The reaction was stirred for 30 min at room temperature and exposed to vacuum for 30 min. Hoveyda-Grubbs 2nd generation catalyst (1.8 mg, 0.0029 mmol) was added and the reaction was heated at 45 °C under argon for 24 h. The reaction was pipetted drop-wise into a centrifuge tube containing hexanes (35 mL) and a precipitate was formed. The mixture was centrifuged to separate the solids. The solids were washed with hexanes (2 x 10 mL) and collected by centrifugation each time. The product was further purified by passing through a short plug of silica gel using chloroform as the eluent to yield a green-yellow solid (16 mg, 51 %). Physical data for the product 16: 1H NMR (400 MHz, Chloroform-d) δ 8.69 (s, 6H), 8.32 (s, 6H), 8.14 – 8.03 (m, 18H), 7.88 (s, 6H), 7.83 (d, J = 7.9 Hz, 12H), 7.68 (d, J = 8.3 Hz, 6H), 7.48 (d, J = 8.7 Hz, 6H), 7.43 – 7.31 (m, 18H), 4.26 (s, 12H), 1.87 (s, 12H), 1.23 (s, 156H), 0.85 (t, J = 6.8 Hz, 18H); 13C NMR (100 MHz, CDCl3) δ 155.9, 144.3, 143.4, 142.1, 140.5, 139.7, 136.1, 129.2, 129.0, 127.8, 126.3, 125.8, 124.7, 123.5, 123.4, 120.6, 117.9, 112.0, 109.2, 109.2, 43.5, 32.7, 32.0, 30.9, 30.0, 29.2, 27.5, 22.8, 14.2; MS (MALDI): Calc’d for C228H276N12 [M+]

3182.20; Found 3182.21.

S8    

3) GPC Data

Figure S1. GPC trace macrocycle 13: blue (crude); red (purified).

Figure S2. GPC trace macrocycle 14: blue (crude); red (purified).

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S9    

Figure S3. GPC trace of crude product mixture of cage 16: Green = 2 h, purple = 4.5 h, red = 8.5 h, blue = 18 h, orange = 24 h.

Figure S4. GPC trace of crude product mixture of cage 16: step-wise ODCC (blue); simultaneous addition of TFA and HG2 (red).

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S10    

4) MALDI-MS spectrum

 

Figure S5. MALDI-MS spectrum of the crude product mixture of cage 16 under the simultaneous reaction conditions: simultaneous addition of TFA and HG2. Cage 16 (m/z 3181.77) and imine intermediate (m/z 1635.06)

Imine intermediate (m/z 1635.06)

0 10 20 30 40 50 60 70 80 90

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Inte

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1635.06 3181.77

S11    

5) NMR of Selected Compounds

S12    

S13    

S14    

S15    

S16    

S17    

1H NMR of Compound 13

S18    

HSQC of Compound 13

Blue = CH2, Red = CH, CH3

S19    

HMBC of Compound 13

S20    

1H NMR of Compound 14

S21    

HSQC of Compound 14

Blue = CH2, Red = CH, CH3

S22    

HMBC of Compound 14

S23    

1H NMR of Compound 16

S24    

HSQC of Compound 16

Blue = CH2, Red = CH, CH3

S25    

HMBC of Compound 16

S26    

6) References

(1)Jyothish,  K.;  Wang,  Q.;  Zhang,  W.  Adv.  Synth.  Catal.  2012,  354,  2073.  (2)Song,  Y.  B.;  Di,  C.  A.;  Wei,  Z.  M.;  Zhao,  T.  Y.;  Xu,  W.;  Liu,  Y.  Q.;  Zhang,  D.  Q.;  Zhu,  D.  B.  Chem.  Eur.  J.  

2008,  14,  4731.  (3)Kotha,  S.;  Shah,  V.  R.  Synthesis  2007,  3653.  (4)Bao,  C.  Y.;  Jin,  M.;  Lu,  R.;  Song,  Z.  G.;  Yang,  X.  C.;  Song,  D.  P.;  Xu,  T.  H.;  Liu,  G.  F.;  Zhao,  Y.  Y.  

Tetrahedron  2007,  63,  7443.  (5)Zhang,  C.;  Wang,  Q.;  Long,  H.;  Zhang,  W.  J.  Am.  Chem.  Soc.  2011,  133,  20995.  (6)Chen,  Z.;  Dreyer,  D.  R.;  Wu,  Z.  Q.;  Wiggins,  K.  M.;  Jiang,  Z.  H.;  Bielawski,  C.  W.  J.  Polym.  Sci.,  Part  A:  

Polym.  Chem.  2011,  49,  1421.  (7)Denmark,  S.  E.;  Butler,  C.  R.  Org.  Lett.  2006,  8,  63.  (8)Zhang,  S.  F.;  Zhou,  D.  H.;  Yang,  J.  Z.  Dyes  Pigments  1995,  27,  287.