www.sciencemag.org/cgi/content/full/330/6000/66/DC1

Supporting Online Material for

Allosteric Supramolecular Triple-Layer Catalysts

Hyo Jae Yoon, Junpei Kuwabara, Jun-Hyun Kim, Chad A. Mirkin*

*To whom correspondence should be addressed. E-mail: chadnano@northwestern.edu

Published 1 October 2010, Science 330, 66 (2010) DOI: 10.1126/science.1193928

This PDF file includes:

Materials and Methods SOM Text Figs. S1 to S12 Tables S1 to S3 NMR Spectra References

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1. General Methods and Instrument Details

All reactions were carried out under an inert atmosphere of nitrogen using standard Schlenk techniques or an inert atmosphere glove box, unless otherwise noted. All glassware was dried in a hot oven for at least 48 h. Tetrahydrofuran (THF), diethyl ether (Et2O), dichloromethane (CH2Cl2), toluene and hexanes were dried and purified with activated alumina columns as described by Grubbs et al (S1). All solvents were degassed via N2 bubbling for at least 2 h prior to use. Deuterated solvents were purchased from Cambridge Isotope Laboratories Inc. All catalytic reactions were run under anhydrous and O2-free conditions. In a typical catalytic experiment, solvents were degassed for at least 2 h by N2 bubbling, and dried over activated molecular sieve (4 Ǻ) for at least 24 h. ε-Caprolactone was purchased from Aldrich Chemical Company, dried in CaH2 and distilled under reduced pressure. NaBArF (BArF = tetrakis[(3,5-trifluoromethyl)phenyl]borate)(S2), N-(2-chloroethyl)-N-phenylaniline(S3), 1,4-bis(diphenylphosphanylethyl-sulfanyl)benzene (S4), and Al{(µ-OEt)2AlMe}3 (S5) were synthesized according to literature methods. All other chemicals were used as received from Aldrich Chemical Company. Reactions were monitored by thin layer chromatography (TLC) with 200 μm pre-coated silica gel plate (Baker-flex precoated flexible TLC, 2.5 cm x 7.5 cm). Visualization was accomplished with either UV light, or by immersion in solution of phosphomolybdic acid (PMA) followed by heating on a hot plate for about 10 sec. Purification of reaction products was carried out by flash column chromatography using silica gel produced by EMD Chemical (pore size: 60 Ǻ, particle size: 40-63 μm, sorbents for preparative column chromatography). 1H NMR (400.13 MHz) and 13C{1H} NMR (100.61 MHz) spectra were recorded on a Bruker Avance III 400 MHz FT-NMR spectrometer and referenced to relative residual proton resonances. 31P{1H} NMR (161.98 MHz) spectra were recorded on a Bruker Avance III 400 MHz FT-NMR spectrometer and referenced relative to an external 85% H3PO4 standard. All chemical shifts are reported in ppm, and data were reported as br = broad, s = singlet, d = doublet, t = triplet, q = quartet, and m = multiplet. High resolution mass spectra (either electrospray ionization (ESI), atmospheric pressure photoionization (APPI), or electron impact (EI) ionization) were recorded on a Micromass Quatro II triple quadrupole mass spectrometer, an Agilent 6210 LC-TOF with Agilent 1200 HPLC induction mass-spec system instrument, and a Thermo Finnigan MAT 900 spectrometer, respectively. The molecular weights of polymers were measured relative to polystyrene standards on a Waters gel-permeation chromatography (GPC) equipped with Breeze software, a 717 autosampler, Shodex KF-G guard column, KF-803L and KF-806L columns in series, a Waters 2440 UV detector, and a 410 RI detector. HPLC-grade THF was used as an eluent at a flow rate of 1.0 mL/min, and the instrument was calibrated using polystyrene standards (Aldrich, 15 standards, 760-1,800,000 Daltons). The polymer samples were completely dried, resuspended in HPCL-grade THF (~1 mg/mL), and sonicated (Fisher FS6 Ultrasonic Cleaner) for 2 min before GPC analysis. For the thermal analyses, the Differential Scanning Calorimetry (DSC) measurements were carried out using a differential scanning calorimeter (DSC, Mettler-Toledo DSC 822e, second heat), calibrated with an indium standard, and using sample masses of 3 - 6 mg. Dry N2 was passed

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(50 mL/min) through the DSC cell during measurement. All samples were heated at a rate of 10 o

C/min from -40 to 100 oC. All samples were completely dried before analysis. Crystallographic data were collected using APEX2 V2.1-4 (Bruker, 2007) detector and processed using SAINTPLUS from Bruker.

2. Synthetic Methods.

Figure S1. Synthesis of 1-chloro-2-diphenylphosphinoethane.

1-Chloro-2-diphenylphosphinoethane. Under N2 atmosphere, a THF solution of KPPh2 (0.5 M, 150 mL, 75 mmol) was added dropwise to N2-saturated 1,2-dichloroethane (1000 mL, 12.66 x103 mmol) for 1 hr at room temperature. After being stirred for 2 h, the reaction solution was concentrated in vacuo, extracted with CH2Cl2 and H2O, dried over Na2SO4, and concentrated in vacuo. The crude product was suspended in a mixture of hexanes and ethanol (approximately 30:1, v/v), and the resulting suspension was sonicated for 5 min, placed in a freezer for 24 h, and then filtered a white crystalline solid and washed with ethanol and hexanes to afford a product in 74% yield. 1H NMR (400.13 MHz, CD2Cl2): δ 7.50 – 7.27 (m, 10H, ArH), 3.69 – 3.53 (m, 2H, CH2), 2.65 – 2.52 (m, 2H, CH2); 13C{1H} NMR (100.62 MHz, CD2Cl2): δ 137.96 (d, JC-P = 13.0 Hz), 133.23 (d, JC-P = 19.1 Hz), 129.55, 129.23 (d, JC-P = 6.0 Hz), 42.50 (d, JC-P = 28.2 Hz), 32.92 (d, JC-P = 16.1 Hz). 31P{1H} NMR (161.98 MHz, CD2Cl2): δ -19.25 (s). HRMS (EI, m/z): [M]+ calcd for C14H14ClP, 248.0522; found, 248.0512.

Figure S2. Synthesis of model triple-layer complex S5.

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N,N-Diphenyl-N-(2-diphenylphosphanylethyl)amine (S2). A THF solution of KPPh2 (0.5 M, 24.4 mL, 12.19 mmol) was added dropwise to a THF (100 mL) solution of N,N-diphenyl-N-(2-chloroethyl)amine S1 (2.824 g, 12.19 mmol) under N2 atmosphere at room temperature. The reaction solution was stirred for 3 h before the solvent was removed in vacuo. The crude product was extracted with CH2Cl2 and H2O, dried over Mg2SO4, and purified via silica-gel column chromatography using CH2Cl2/hexanes (v/v, 1:5 → 1:1) to afford a product S2 in 70% yield. 1H NMR (400.13 MHz, CD2Cl2): δ 7.47 – 6.93 (m, 20H, ArH), 3.87 – 3.85 (m, 2H, NCH2), 2.51 – 2.47 (m, 2H, PCH2); 13C{1H} NMR (100.62 MHz, CD2Cl2): δ 148.04, 138.77 (d, JC-P = 13.1 Hz), 133.31 (d, JC-P = 19.1 Hz), 129.80, 129.33, 129.08 (d, JC-P = 7.0 Hz), 121.86, 121.46, 49.65 (d, JC-P = 27.2 Hz), 26.50 (d, JC-P = 14.1 Hz); 31P{1H} NMR (161.98 MHz, CD2Cl2): δ -20.88 (s); HRMS (APPI, m/z): [M+H]+ calcd for C26H25NP, 382.1725; found, 382.1735.

Semi-open complex (S4). Under N2 atmosphere, a CH2Cl2 (10 mL) solution of [Rh(cod)Cl]2 (31.6 mg, 0.04400 mmol, cod = 1,5-cyclooctadiene) was added dropwise for 15 min into a vigorously stirred CH2Cl2 (10 mL) solution of compound S3 (20.0 mg, 0.03529 mmol) and compound S2 (26.9 mg, 0.07058 mmol) at room temperature. The resulting solution was stirred overnight before the volatiles were removed in vacuo. The crude product was sonicated in Et2O/hexanes (v/v, 1:1) for 2 h. The resulting yellow solid was collected, washed thoroughly with hexanes and Et2O, and dried under vacuum to afford product S4 as in 97% yield. 1H NMR (400.13 MHz, CD2Cl2): δ 8.17 (s, 4H, ArH), 7.61 – 6.73 (m, 60H, ArH), 4.07 – 3.98 (m, 4H, NCH2CH2P), 2.62 – 2.48 (m, 4H, SCH2CH2P), 2.48 – 2.36 (NCH2CH2P), 2.33 – 2.23 (m, 4H, SCH2CH2P); 31P{1H} NMR (161.98 MHz, CD2Cl2): δ 72.95 (dd, JRh-P = 184.68 Hz, JP-P = 42.12 Hz), 27.31 (dd, JRh-P = 166.86 Hz, JP-P = 42.12 Hz); HRMS (ESI, m/z): [M-Cl]+ calcd for C86H80ClN2P4Rh2S2, 1569.2512; found, 1569.2455; [M-2Cl]2+ calcd for C86H80N2P4Rh2S2, 767.1412; found, 767.1411.

Closed complex (S5). Under N2 atmosphere, a CH2Cl2 (10 mL) solution of NaBArF (33.1 mg, 0.03735 mmol) was added to a CH2Cl2 (10 mL) solution of semi-open complex S4 (30.0 mg, 0.01868 μmol) at room temperature. After being stirred for 1 hr at room temperature, the reaction was concentrated in vacuo, redissolved with CH2Cl2 (2 mL) and stored inside a freezer (-30 oC) for 24 h (NaCl precipitate was observed). The cold CH2Cl2 solution was filtered through Celite, and the filtrate was concentrated in vacuo, recrystallized with CH2Cl2 and hexanes, washed with Et2O and hexanes, and dried under vacuum to afford product S5 in 95% yield. 1H NMR (400.13 MHz, CD2Cl2): δ 7.86 – 6.77 (m, 88H, ArH), 3.81 – 3.58 (m, 4H, NCH2CH2P), 2.65 – 2.51 (m, 4H, SCH2CH2P), 2.45 – 2.36 (m, 4H, NCH2CH2P), 2.36 – 2.25 (m, 4H, SCH2CH2P) ; 31P{1H} NMR (161.98 MHz, CD2Cl2): δ 66.73 (dd, JRh-P = 178.20 Hz, JP-P = 42.12 Hz), 49.95 (dd, JRh-P = 173.34 Hz, JP-P = 42.12 Hz); 11B{1H} NMR (128.39 MHz, CD2Cl2): δ -6.79 (s); 19F{1H} NMR (376.46 MHz, CD2Cl2): δ -62.80 (s). HRMS (ESI, m/z): [M-BArF]+ calcd for C118H92BF24N2P4Rh2S2, 2397.3472; found, 2397.2661; [M-2BArF]2+ calcd for C86H80N2P4Rh2S2, 767.1412; found, 767.1442. Semi-open complex forms after the addition of stoichiometric amount of acetonitrile-d3 or tetrabutylammonium chloride to a CD2Cl2 solution of complex S5.

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This was confirmed by 31P{1H} NMR spectroscopy, which exhibits resonances and splitting patterns that are nearly identical to those observed for complex S4.

Figure S3. Synthesis of ligand S10.

5-(4-Methylthiophenyl)-2-hydroxybenzaldehyde (S8). 4-(Methylthio)phenylboronic acid S6 (5.05 g, 30.06 mmol), 5-bromo-2-hydroxybenzaldehyde S7 (5.5 g, 27.33 mmol), Pd(dppf)Cl2 (1.0 g, 1.367 mmol, dppf = 1,1'-bis(diphenylphosphino)ferrocene), Na2CO3 (8.7 g, 81.99 mmol) and 1,2-dimethoxyethane/H2O (250 mL, v/v, 3:1) were refluxed under N2 atmosphere for 16 h. The reaction mixture was cooled to room temperature before removing the organic solvent in vacuo. After addition of excess conc. HCl, the generated dark brown solid was isolated and washed thoroughly with Et2O. The filtrate was concentrated and purified by silica-gel column chromatography using CH2Cl2/hexanes (v/v, 1:1) as an eluent to afford product S8 as a yellow solid in 79% yield. 1H NMR (400.13 MHz, CD2Cl2): δ 11.01 (s, 1H, OH), 9.87 (s, 1H, CHO), 7.70 – 7.67 (m, 2H, ArH), 7.43 (d, J = 8.4 Hz, 2H, ArH), 7.28 (d, J = 8.4 Hz, 2H, ArH), 7.01 (d, J = 8.4 Hz, 1H, ArH), 2.49 (s, 3H, SCH3); 13C{1H} NMR (100.62 MHz, CD2Cl2): δ 197.23, 161.18, 138.44, 136.15, 135.51, 132.75, 131.83, 127.17, 127.15, 121.11, 118.38, 15.83; HRMS (EI, m/z): [M]+ calcd for C14H12O2S, 244.0553; found, 244.0548.

5-[4-(2-Diphenylphosphanylethylsulfanyl)phenyl]-2-hydroxybenzaldehyde (S9). Caution! Sodium 2-methyl-2-propanethiolate emits a strong odor at low concentrations. This reaction should be carried out with proper attire in a well-ventilated laboratory. 5-(4-Methylthiophenyl)-2-hydroxybenzaldehyde S8 (2.805 g, 11.48 mmol), sodium 2-methyl-2-propanethiolate (3.86 g, 34.45 mmol) and DMF were refluxed under N2 atmosphere for 6 h. After being cooled to 0 oC using an ice bath, the reaction solution was acidified with conc. HCl. The acidic solution was extracted with Et2O and H2O, and the organic layer was washed with H2O until the DMF was completely removed. After being dried over Mg2SO4, the reaction solution was concentrated in vacuo and dried under vacuum. The crude thiol product was used for the next synthetic step

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without further purification. (2-chloroethyl)diphenylphosphine (2.28 g, 9.185 mmol) and Cs2CO3 (2.99 g, 9.185 mmol) were added to a MeCN (100 mL) solution of the crude thiol product, and the resulting mixture was refluxed under N2 atmosphere overnight. After being cooled to room temperature, the organic solvent was removed in vacuo and purified by silica-gel column chromatography using CH2Cl2/hexanes (v/v, 7:4) as an eluent to afford product S9 as a yellow oil in 65% yield. 1H NMR (400.13 MHz, CD2Cl2): δ 11.00 (s, 1H, OH), 9.98 (s, 1H, CHO), 7.78 – 7.76 (m, 2H, ArH), 7.55 – 7.26 (m, 14H, ArH), 7.07 (d, J = 8.8 Hz, 1H, ArH), 3.04 – 2.99 (m, 2H, SCH2), 2.43 – 2.39 (m, 2H, PCH2); 13C{1H} NMR (100.62 MHz, CD2Cl2): δ 197.37, 161.51, 138.50 (d, JC-P = 14.1 Hz), 137.54, 136.03, 135.84, 133.27 (d, JC-P = 19.1 Hz), 132.95, 132.17, 130.12, 129.39, 129.13 (d, JC-P = 7.0 Hz), 127.51, 121.40, 118.58, 30.71 (d, JC-P = 23.1 Hz), 28.70 (d, JC-P = 15.1 Hz). 31P{1H} NMR (161.98 MHz, CD2Cl2): δ -16.33 (s); HRMS (EI, m/z): [M]+ calcd for C27H23O2PS, 442.1151; found, 442.1145.

N,N’-Bis-{5-[4-(2-diphenylphosphanylethylsulfanyl)phenyl]}salicylidene-diaminoethane (S10). Compound S9 (1.719 g, 3.885 mmol), 1,2-diaminoethane (116.7 mg, 1.942 mmol) and EtOH/CH2Cl2 (100 mL, v/v, 1:3) were refluxed for 21 h before the sidearm of the flask was opened under N2 pressure to allow CH2Cl2 to escape until a precipitate was observed. The resulting suspension was placed in a freezer for 18 h, and then filtered in air yielding product S10 as a yellow powder in 84% yield. 1H NMR (400.13 MHz, CD2Cl2): δ 13.27 (s, 1H, OH), 8.47 (s, 2H, N=CH), 7.54 – 7.26 (m, 32H, ArH), 6.98 (d, J = 8.4 Hz, 2H, ArH), 3.99 (s, 4H, N-CH2), 3.01 – 2.96 (m, 4H, SCH2), 2.41 – 2.36 (m, 4H, PCH2); 13C{1H} NMR (100.62 MHz, CD2Cl2): δ 167.08, 161.25, 138.57 (d, JC-P = 3.0 Hz), 138.41, 135.03, 133.25 (d, JC-P = 19.1 Hz), 131.52, 131.29, 130.26, 130.15, 129.36, 129.09 (d, JC-P = 6.0 Hz), 127.43, 119.45, 117.90, 30.81 (d, JC-P = 22.1 Hz), 28.68 (d, JC-P = 15.1 Hz); 31P{1H} NMR(161.98 MHz, CD2Cl2): δ -16.76 (s); HRMS (ESI, m/z): [M+H]+ calcd for C56H50N2O2P2S2, 908.2862; found, 908.2876.

Figure S4. Synthesis of blocking ligand S14.

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N,N-Bis[4-(4-methoxy-3,5-dimethylphenyl)phenyl]amine (S12). N,N-Bis(4-bromophenyl)-amine S11 (3.0 g, 9.712 mmol), 4-methoxy-3,5-dimethylphenylboronic acid (3.47 g, 19.26 mmol), Pd(PPh3)4 (1.06 g, 0.9172 mmol), Na2CO3 (3.89 g, 36.69 mmol) and a mixture of solvents (toluene/EtOH/H2O, v/v/v, 6:1:2, 200 mL) were refluxed under N2 (g) atmosphere overnight. After being cooled to room temperature, the reaction solution was concentrated in vacuo, extracted with CH2Cl2 and H2O, dried over Na2SO4, and purified by silica-gel column chromatography using CH2Cl2/hexanes (v/v, 1:1) as an eluent to afford product S12 as a light yellow solid in 82% yield. 1H NMR (400.13 MHz, CD2Cl2): δ 7.50 (d, J = 7.2 Hz, 4H,ArH), 7.25 (s, 4H, ArH), 7.16 (d, J = 6.8 Hz, 4H, ArH), 6.02 (br, 1H, NH), 3.75 (s, 6H, OCH3), 2.35 (s, 12H, CH3); 13C{1H} NMR (100.62 MHz, CD2Cl2): δ 156.80, 136.67, 134.47, 134.12, 131.64, 128.17, 127.34, 118.45, 60.19, 16.57; HRMS (ESI, m/z): [M+H]+ calcd for C30H32NO2, 438.2428; found, 438.2437.

N,N-Bis[4-(4-methoxy-3,5-dimethylphenyl)phenyl]-N-(2-chloroethyl)amine (S13). NaBH4 (493 mg, 13.03 mmol) was added to a toluene (100 mL) solution of chloroacetic acid (1.62 g, 17.19 mmol), and the resulting mixture was stirred for 2 h at room temperature. A toluene (50 mL) solution of compound S12 (1.14g, 2.605 mmol) was added to the mixture, and the reaction mixture was refluxed for 3 h under N2 atmosphere. After addition of excess amount of aq. NaOH, the organic layer was separated, washed with H2O, dried over Na2SO4, concentrated in vacuo, and purified by silica-gel column chromatography using CH2Cl2/hexanes (v/v, 1:1) as an eluent to afford product S13 in 73%. 1H NMR (400.13 MHz, CD2Cl2): δ 7.50 (d, J = 8.8 Hz, 4H, ArH), 7.23 (s, 4H, ArH), 7.09 (d, J = 8.8 Hz, 4H, ArH), 4.12 (t, J = 7.6 Hz, 2H, NCH2), 3.76 (t, J = 7.6 Hz, 2H, ClCH2); 13C{1H} NMR (100.62 MHz, CD2Cl2): δ 156.98, 146.67, 136.50, 135.12, 131.70, 128.30, 127.48, 121.73, 60.20, 54.20, 41.19, 16.56; HRMS (ESI, m/z): [M-CH2+H]+ calcd for C31H33ClNO2, 486.2194; found, 486.2194.

N,N-Bis[4-(4-methoxy-3,5-dimethylphenyl)phenyl]-N-(2-diphenylphosphanylethyl)amine (S14). A THF solution of KPPh2 (0.5 M, 3.6 mL, 1.808 mmol) was added dropwise to a THF (50 mL) solution of compound S13 (904 mg, 1.808 mmol) under N2 atmosphere at room temperature. The reaction solution was stirred for 1 hr before the solvent was removed in vacuo. The crude product was purified via silica-gel column chromatography using CH2Cl2/hexanes (v/v, 1:1) as an eluent to afford product S14 in 82% yield. 1H NMR (400.13 MHz, CD2Cl2): δ 7.47 – 7.42 (m, 14H, ArH), 7.21 (s, 4H, ArH), 6.97 (d, J = 8.4 Hz, 4H, ArH), 3.88 – 3.86 (m, 2H, NCH2), 3.74 (s, 6H, OCH3), 2.51 – 2.47 (m, 2H, PCH2), 2.33 (s, 12H, ArCH3); 13C{1H} NMR (100.62 MHz, CD2Cl2): δ 156.87, 146.71, 138.64 (d, JC-P = 12.1 Hz), 136.58, 134.61, 133.33 (d, JC-P = 19.1 Hz), 131.65, 129.39, 129.10 (d, JC-P = 7.0 Hz), 128.09, 127.40, 121.66, 60.19, 49.86 (d, JC-P = 26.2 Hz), 26.54 (d, JC-P = 14.1 Hz), 16.56; 31P{1H} NMR (161.98 MHz, CD2Cl2): δ -21.12 (s); HRMS (ESI, m/z): [M+H]+ calcd for C44H45NO2P, 650.3189; found, 650.3220.

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Figure S5. Synthesis of functional triple-layer complex S17.

Semi-open complex-H2 (S15). Under N2 atmosphere, a dry THF (20 mL) solution of [Rh(coe)2Cl]2 (31.6 mg, 0.04400 mmol, coe = cyclooctene) was added dropwise for 1 hr into a vigorously stirred dry THF (20 mL) solution of compound S10 (40.0 mg, 0.04400 mmol) and compound S14 (57.2 mg, 0.08800 mmol) at room temperature. The resulting solution was stirred overnight before the volatiles were removed in vacuo. The crude product was recrystallized with THF and hexanes. After being filtered and isolated, the solid was washed thoroughly with hexanes and dried under vacuum to afford product S15 as a yellow powder in 92% yield. 1H NMR (400.13 MHz, CD2Cl2): δ 13.30 (s, 2H, OH), 8.29 (s, 2H, N=CH), 8.23 (d, J = 8.4 Hz, 4H, ArH), 7.59 – 6.90 (m, 74H, ArH), 4.19 – 4.18 (m, 4H, NCH2CH2P), 3.90 (s, 4H, NCH2CH2N), 3.72 (s, 12H, OCH3), 2.56 – 2.45 (m, 8H, SCH2CH2P & NCH2CH2P), 2.34 – 2.24 (m, 28H, ArCH3 & SCH2CH2P); 31P{1H} NMR (161.98 MHz, CD2Cl2): δ 71.87 (dd, JRh-P = 184.68 Hz, JP-

P = 42.12 Hz), 26.36 (dd, JRh-P = 166.86 Hz, JP-P = 40.50 Hz); HRMS (ESI, m/z): [M-2Cl]2+ calcd for C144H138N4O6P4Rh2S2, 1206.3554; found, 1206.3548.

Semi-open complex-Al(III)OEt (S16). Before synthesis, compound S15 was dried under vacuum at 60 oC for 4 days. Al{(µ-OEt)2AlMe}3 (0.07619 M in dry toluene, 17.6 μL, 1.341 μmol) was added to a toluene-d8 (1.5 mL) solution of compound S15 (10 mg, 4.023 μmol) at 0

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oC under N2 atmosphere, and the resulting solution was stirred for 2 h at 0 oC under N2 atmosphere. The reaction solution was slowly warmed to room temperature, stirred for 6 h at room temperature, and for 30 min at 80 oC under N2 atmosphere. After being cooled down to room temperature, the reaction solution was filtered to remove insoluble impurities, concentrated under reduced pressure, washed with dry hexanes, and dried under vacuum condition to afford product S16 in 88% yield. As an alternative synthetic method, AlEt3 (16.1 μL, 16.10 μmol, 1.0 M in hexane) was added to a dry toluene-d8 (5 mL) solution of compound S15 (40 mg, 16.10 μmol) at 0 oC, and the resulting solution was stirred for 2 h at 0 oC, for 6 h at room temperature, and for 30 min at 80 oC (Formation of the resulting Al(III)Et-complex was confirmed by mass spectrometry. HRMS (ESI, m/z): [M-2Cl]2+ calcd for C146H141AlN4O6P4Rh2S2, 1233.3579; found, 1233.3574.) To the reaction solution was added pure EtOH (1.01 eq, EtOH was distilled and dried over molecular sieve to remove moisture prior to use.) at room temperature, and the resulting solution was stirred for additional 6 h at room temperature and for 30 min at 80 oC. The reaction solution was recrystallized with dry hexanes to afford product S16 in 89% yield. 1H NMR (400.13 MHz, CD2Cl2): δ 8.22 (br s, 2H, N=CH), 8.05 – 6.72 (m, 78H, ArH), 4.30 – 3.85 (br m, 6H, NCH2CH2P & NCH2CH2N), 3.73 (s, 12H, ArOCH3), 3.64 (q, J = 6.8 Hz, 4H, AlOCH2CH3 & NCH2CH2N), 2.68 – 2.42 (br m, 8H, SCH2CH2P & NCH2CH2P), 2.31 – 2.10 (s, 28H, ArCH3 & SCH2CH2P), 1.15 (t, J = 6.8 Hz, 3H, AlOCH2CH3); 31P{1H} NMR (161.98 MHz, CD2Cl2): δ 73.16 (dd, JRh-P = 186.28 Hz, JP-P = 42.11 Hz), 27.69 (dd, JRh-P = 166.84 Hz, JP-P = 40.50 Hz); 1H NMR (400.13 MHz, toluene-d8): δ 8.25 (s, br, 2H, N=CH), 8.13 – 6.81 (m, 102H, ArH), 3.69 – 3.14 (m, br, 22H, NCH2CH2P, NCH2CH2N, AlOCH2CH3 & ArOCH3), 2.35 – 1.91 (m, 36H, NCH2CH2P, SCH2CH2P, & ArCH3), 0.90 (m, br, 3H, AlOCH2CH3); 31P{1H} NMR (161.98 MHz, toluene-d8): δ 72.33 (dd, JRh-P = 187.92 Hz, JP-P = 38.88 Hz), 26.83 (dd, JRh-P = 166.86 Hz, JP-P = 42.12 Hz); HRMS (ESI, m/z): [M-2Cl-OEt]3+ calcd for C144H136AlN4O6P4Rh2S2, 812.5587; found, 812.5590; [M-2Cl]2+ calcd for C146H141AlN4O7P4Rh2S2, 1241.3553; found, 1241.3344.

Closed complex (S17). Under N2 atmosphere, NaBArF (0.01281 M in CD2Cl2 or toluene-d8, 0.63 mL, 8.046 μmol) was added to a toluene-d8 (2.05 mL) solution of semi-open complex S16 (10.3 mg, 4.023 μmol) at room temperature (alternatively, LiB(C6F5)4·Et2O can be used instead of NaBArF. High purity (>98%), anhydrous NaBArF is completely soluble in toluene. Sonication may be useful.). After being stirred for 20 min, the resulting mixture was filtered, and the filtrate was left under reduced pressure to afford a toluene-d8 solution of a product S17 in quantitative yield. 1H NMR (400.13 MHz, CD2Cl2): δ 8.23 (s, 2H, N=CH), 7.90 – 6.95 (m, 100H, ArH), 6.66 (d, J = 2.0 Hz, 2H, ArH), 4.23 – 4.10 (m, 2H, NCH2), 3.93 – 3.56 (m, 20H, NCH2, NCH2CH2P, OCH3 & AlOCH2CH3) 2.63 – 2.09 (m, 36H, NCH2CH2P, SCH2CH2P, & ArCH3), 1.17 (br, m, 3H, AlOCH2CH3); 1H NMR (400.13 MHz, toluene-d8): δ 8.25 (s, br, 2H, N=CH), 8.13 – 6.81 (m, 102H, ArH), 3.69 – 3.14 (m, br, 22H, NCH2CH2P, NCH2CH2N, AlOCH2CH3 & ArOCH3), 2.35 – 1.91 (m, 36H, NCH2CH2P, SCH2CH2P, & ArCH3), 0.90 (m, br, 3H, AlOCH2CH3); 31P{1H} NMR (161.98 MHz, CD2Cl2): δ 66.86 (dd, JRh-P = 179.80 Hz, JP-P = 42.11 Hz), 50.07 (dd, JRh-P = 171.70 Hz, JP-P = 42.11 Hz); 31P{1H} NMR (161.98 MHz, toluene-

  10

d8): δ 66.03 (dd, JRh-P = 178.20 Hz, JP-P = 42.12 Hz), 49.09 (dd, JRh-P = 171.72 Hz, JP-P = 42.12 Hz); 11B{1H} NMR (128.39 MHz, CD2Cl2): δ -6.80 (s); 19F{1H} NMR (376.46 MHz, CD2Cl2): δ -62.77 (s); HRMS (ESI, m/z): [M-2BArF-OEt]3+ calcd for C144H136AlN4O6P4Rh2S2, 812.5587; found, 812.5610; [M-2{B(C6F5)4}]2+ calcd for C146H141AlN4O7P4Rh2S2, 1241.3553; found, 1241.3425. (For LiB(C6F5)4·Et2O, [M-2{B(C6F5)4}-OEt]3+ calcd for C144H136AlN4O6P4Rh2S2, 812.5592; found, 812.5585; [M-2{B(C6F5)4}]2+ calcd for C146H141AlN4O7P4Rh2S2, 1241.3559; found, 1241.3344). Semi-open complexes could form by adding a stoichiometric amount of acetonitrile-d3 or tetrabutylammonium chloride to a toluene-d8 or CD2Cl2 solution of complex S17, which was confirmed by 1H and 31P{1H} NMR spectroscopy and comparison with NMR data for complex S16. ESI-MS studies are also consistent with the proposed structures.

Closed complex-H2 (S18). Under N2 atmosphere, a CH2Cl2 (10 mL) solution of NaBArF (14.5 mg, 0.01642 mmol) was added dropwise for 10 min into a CH2Cl2 (10 mL) solution of compound S15 (20.4 mg, 8.208 µmol) at room temperature. The resulting solution was stirred for 3 h before the volatiles were removed in vacuo. The crude product was dissolved in a minimal amount of CH2Cl2 and filtered off to remove insoluble solid. The resulting filtrate was recrystallized with CH2Cl2 and hexanes and dried under vacuum to afford product S18 in 96% yield. 1H NMR (400.13 MHz, CD2Cl2): δ 13.47 (br, s, 2H, OH), 8.37 (s, 2H, N=CH), 7.88 – 6.43 (m, 102H, ArH), 4.07 (s, 4H, NCH2CH2N), 3.83 – 3.49 (m, 16H, NCH2CH2P & OCH3), 2.63 – 2.14 (m, 36H, SCH2CH2P & NCH2CH2P & ArCH3); 31P{1H} NMR (161.98 MHz, CD2Cl2): δ 67.09 (dd, JRh-P = 178.18 Hz, JP-P = 42.11 Hz), 50.29 (dd, JRh-P = 173.32 Hz, JP-P = 42.11 Hz); 11B{1H} NMR (128.39 MHz, CD2Cl2): δ -6.80 (s); 19F{1H} NMR (376.46 MHz, CD2Cl2): δ -62.79 (s); HRMS (ESI, m/z): [M-2BArF]2+ calcd for C144H138N4O6P4Rh2S2, 1206.3554; found, 1206.3536. The corresponding semi-open complex forms by adding a stoichiometric amount of acetonitrile-d3 or tetrabutylammonium chloride to a toluene-d8 or CD2Cl2 solution of complex S18, which was confirmed by 1H and 31P{1H} NMR spectroscopy. ESI-MS studies are also consistent with the proposed structures.

3. Catalytic Methods.

In a typical experiment, polymerization was monitored by 1H NMR spectroscopy. The conversions (%) were determined by the ratio of the integrations of resonances for the monomer and a polymer in the 1H NMR spectra. All catalytic reactions were run under highly anhydrous and O2-free conditions. Each catalyst was freshly synthesized in situ and transferred to a reaction vessel for polymerization. Each catalyst (2.09 mM), ε-caprolactone (ε-CL) (331 mM or 541 mM) and toluene-d8 (total volume: 1.5 mL) was transferred into an air-free NMR tube, and the resulting reaction solution was heated at 70 ± 3 oC or 90 ± 3 oC. (It was observed that a catalyst decomposed under very small amount of oxygen or moisture.) For GPC samples, the polymer (~5 mg) with a dark yellow color was dissolved in HPLC-grade THF (~2 mL) in a 20 mL vial,

  11

followed by the addition of hexanes (10 mL). The resulting mixture was centrifuged (Eppendorf centrifuge 5804R, 15 amp version, 3000 rpm for 15 minutes) to remove free catalyst and any impurities from the polymer. After decanting the mother liquor, the precipitated solids were rinsed with hexanes and dried under vacuum to give a light yellow solid. In experiments for reversibility, similar experimental conditions were employed with the catalytic methods mentioned above. Under N2 atmosphere, semi-open complex (2.09 mM), ε-caprolactone (105 mM) and toluene-d8 (total volume: 30 mL) was transferred into a dry Schlenk flask, and the solution was heated at 70 ± 2 oC. At various times, a 2 mL aliquot was taken from the solution and characterized by 1H NMR spectroscopy and GPC. For analysis of 31P{1H} NMR spectroscopy, 4 mL aliquot was taken from the solution, quickly concentrated up to ~ 0.5 mL under reduced pressure, and mixed with CD2Cl2 (~ 2 mL) for NMR analysis. Polymer was purified and analyzed by the same procedures with ones mentioned above. NMR spectroscopic data of ε-caprolactone produced by a triple-layer catalyst:(S6) 1H NMR (400.13 MHz, toluene-d8): δ 3.97 (br, m, [O(C=O)CH2CH2CH2CH2CH2]n), 3.56 (br, m, CH2OCO of end group), 2.12 (br, m, [O(C=O)CH2CH2CH2CH2CH2]n), 1.62 – 1.08 (br, m, [O(C=O)CH2CH2CH2CH2CH2]n); 13C{1H} NMR (100.62 MHz, toluene-d8): δ 172.56, 64.02, 34.11, 28.80, 25.85, 24.92.

  12

 

S16

Figure S6. (A) Representative reaction scheme of ring opening polymerization of ε-caprolactone catalyzed by semi-open Al(III)OEt complex S16. (B) A typical 1H NMR trace for the reaction. The reaction starts with (a) which corresponds to t = 0 hr (b: 1.8, c: 3.6, d: 6.8, e: 23, f: 47, g: 71, h: 138 (hours)). The conversion of monomer was determined by comparison of integrations of peaks H1 and H2. (C) Control experiment with complex S15 to confirm that Rh (I) moieties are catalytically inactive. Experimental conditions: catalyst (2.09 mM), є-caprolactone (541 mM) in toluene-d8 under O2-free atmosphere.

 

  13

 

Figure S7. GPC traces of polycaprolactones produced by the open triple-layer catalyst S16. Inset: reaction temperature/[ε-CL].

Table S1. GPC analyses of polycaprolactones produced by the triple-layer catalyst S16.

Mna Mn

b Mwb PDIb

70 oC/331 mM 16500 17800 20800 1.17

90 oC/331 mM 18100 21300 24800 1.17

90 oC/541 mM 29000 30000 35400 1.18

a = theoretical, b = experimental.

 

  14

Figure S8. Traces of Differential Scanning Calorimetry (DSC) thermograms of polymers produced by triple-layer catalyst.

 

Figure S9. Conversion of ε-caprolactone as a function of time. 31P{1H} NMR spectra indicate the corresponding structures in each region. (1) Semi-open structure, 0 h ~ before addition of NaBArF. (2) Closed structure, addition of NaBArF ~ before addition of MeCN-d3 (Small amount of NaCl precipitate was observed). (3) Semi-open structure, after addition of MeCN-d3. (Here, acetonitrile, a small molecule rather than elemental anion, was employed as an allosteric effector; this proof-of-concept demonstration suggests many small molecules and elemental anions (S7-S9) arecandidates for regulating related molecular structures.)

  15

4. X-ray Crystallographic Study. A yellow plate crystal of compound S4 having approximate dimensions of 0.36 x 0.20 x 0.04 mm was mounted using oil (Infineum V8512) on a glass fiber. All measurements were made on a CCD area detector with graphite monochromated MoK\α radiation. The data were collected at a temperature of 100(2)K with a theta range for data collection of 1.07 to 30.17º. Data were collected in 0.5º oscillations with 20 second exposures. The crystal-to-detector distance was 60.00 mm. Of the 34356 reflections which were collected, 11905 were unique (Rint = 0.0567). The data were corrected for Lorentz and polarization effects. The structure was solved by direct methods and expanded using Fourier techniques (S10). The non-hydrogen atoms were refined anisotropically. Hydrogen atoms were included in idealized positions, but not refined. The final cycle of full-matrix least-squares refinement (S11) on F2 was based on 11905 reflections and 469 variable parameters and converged (largest parameter shift was 0.001 times its esd) with unweighted and weighted agreement factors of: R1 = Σ| |Fo|-|Fc| |/Σ|Fo| = 0.0323, wR2 = {Σ[w(Fo

2-Fc2)2]/Σ[w(Fo

2)2]}1/2 = 0.0699. The weighting scheme was calc. calc w=1/[σ2(Fo

2)+(0.0359P)2 + 0.0000P] where P=(Fo2+2Fc

2)/3. The standard deviation of an observation of unit weight (S12) was 0.959. The weighting scheme was based on counting statistics and included a factor to downweight the intense reflections. Plots of Σ w (|Fo| - |Fc|)2 versus |Fo|, reflection order in data collection, sin θ/λ and various classes of indices showed no unusual trends. The maximum and minimum peaks on the final difference Fourier map corresponded to 0.744 and -0.831 e-/Å3, respectively. Neutral atom scattering factors were taken from Cromer and Waber (S13). Anomalous dispersion effects were included in Fcalc (S14); the values for Df' and Df" were those of Creagh and McAuley (S15). The values for the mass attenuation coefficients are those of Creagh and Hubbell (S16). All calculations were performed using the Bruker SHELXTL3 crystallographic software package. A yellow plate crystal of compound S5 (0.54 x 0.34 x 0.02 mm) was characterized in a manner similar to that of S4.

  16

 

 

Figure S10. ORTEP diagrams of S4 (A) packing mode with solvent (CH2Cl2) molecules; B) without solvent molecules). Thermal ellipsoids drawn to 50% probability. Hydrogen atoms have been omitted for clarity. Labeling and coloring scheme is as follows: Rh (orange); P (green); S (yellow); N (dark brown); Cl (blue); C (gray).

  17

Table S2. Crystal data and structure refinement for compound S4.

_________________________________________________________________________ 

Empirical formula C88H84Cl6N2P4Rh2S2

Formula weight 1776.09

Temperature 100(2) K

Wavelength 0.71073 Å

Crystal system, space group Triclinic, P-1

Unit cell dimensions a = 10.26420(10) Å α = 104.3010(10) º

b = 11.48350(10) Å β = 91.4510(10) º

c = 19.9161(3) Å γ = 115.1480(10) º

Volume 2036.28(4) Å3

Z, Calculated density 1, 1.448 Mg/m3

Absorption coefficient 0.779 mm-1

F(000) 910

Crystal size 0.36 x 0.20 x 0.04 mm

Theta range for data collection 1.07 to 30.17 º

Limiting indices -14<=h<=14, -16<=k<=16, -28<=l<=28

Reflections collected/unique 34356 / 11905 [R(int) = 0.0567]

Completeness to theta = 30.17 98.6 %

Absorption correction Numerical

Max. and min. transmission 0.9680 and 0.7658

Refinement method Full-matrix least-squares on F2

Data/restraints/parameters 11905/0/469

Goodness-of-fit on F^2 0.959

Final R indices [I>2sigma(I)] R1 = 0.0323, wR2 = 0.0699

R indices (all data) R1 = 0.0489, wR2 = 0.0818

  18

Largest diff. peak and hole 0.744 and -0.831 e-/Å3

_________________________________________________________________________ 

Figure S11. ORTEP diagrams of S5 (A) packing mode with counter anions; B) without counter anions). Thermal ellipsoids drawn to 50% probability. Hydrogen atoms and solvent molecules have been omitted for clarity. Labeling and coloring scheme is as follows: Rh (orange); P (green); S (yellow); N (dark brown); F (pink); B (purple); C (gray).

  19

Table S3. Crystal data and structure refinement for compound S5.

_________________________________________________________________________ 

Empirical formula C174H160B2F48N2P4Rh2S2

Formula weight 3606.48

Temperature 100(2) K

Wavelength 0.71073 Å

Crystal system, space group Triclinic, P-1

Unit cell dimensions a = 13.2436(3) Å α = 106.270(2) º

b = 17.5190(4) Å β = 95.613(2) º

c = 19.8005(7) Å γ = 110.155(1) º

Volume 4042.56(19) Å3

Z, Calculated density 1.48133 Mg/m3

Absorption coefficient 0.379 mm-1

F(000) 1842

Crystal size 0.54 x 0.34 x 0.02 mm

Theta range for data collection 1.10 to 30.04 º

Limiting indices -18<=h<=18, -24<=k<=23, -27<=l<=27

Reflections collected/unique 67398 / 22819 [R(int) = 0.0552]

Completeness to theta = 30.04 96.4 %

Absorption correction Numerical

Max. and min. transmission 0.9929 and 0.8743

Refinement method Full-matrix least-squares on F2

Data/restraints/parameters 22819 /0/966

Goodness-of-fit on F^2 1.014

Final R indices [I>2sigma(I)] R1 = 0.0693, wR2 = 0.1902

R indices (all data) R1 = 0.1331, wR2 = 0.2166

  20

Largest diff. peak and hole 2.186 and -1.485 e-/Å3

_________________________________________________________________________ 

5. Structure modeling study

Structure of complex 10 was optimized in the computer by using an MM+ force field with a Polak-Ribiere conjugate gradient algorithm and with a gradient convergence criterion of 0.01 kcal/mol in HyperChem (S17).

  21

Figure S12. Side (A and C) and top (B and D) views of a model of the optimized structure for closed complex 10. (A and B: ball and stick, C and D: space-filling). Labeling and coloring schemes are as follows: Rh (pink); P (green); S (yellow); N (blue); C (cyan). 

6. Diffusion NMR spectroscopic experiments

All diffusion NMR experiments were performed using a 5-mm PABBO probe on a Bruker Avance III 400 MHz FT-NMR spectrometer in CD2Cl2 at 303 K. Stimulated echo sequence with bipolar gradient pulse pair (BPPSTE) was used to measure diffusion coefficients (S18). The resonance frequency of 1H nuclei was 400.13 MHz. The separation between the leading edges of the gradient pulses, Δ, was set to 50 – 100 ms. The gradient pulse width, δ, was 1 – 2 ms. Prior to the acquisition of NMR signals, the adsorbed sample was equilibrated for at least 20 minutes at the desired temperature. The error in temperature was less than 0.1 K. In DOSY (Diffusion Ordered Spectroscopy) experiment, complex S17 showed a smaller value of diffusion coefficient (7.688 x 10-10 m2·s-1) than one of complex S5 (9.978 x 10-10 m2·s-1), indicating that compound S17 has a larger hydrodynamic radius than that of S5 based upon the Stokes-Einstein equation (S19),

  22

rkTDπη6

=

where k is the Boltzmann constant, T the temperature, η the viscosity of the solvent and r the hydrodynamic radius of the molecule. (Experimental numerical values: k = 1.38 x 10-23 J·K-1, T = 303 K, η = 0.393 mPa·s at 303 K) (S20) (Because the Stokes-Einstein equation is for spherical molecule, there could be error associated with estimating the exact hydrodynamic radii of two compounds S17 and S5. However, there is no doubt that the hydrodynamic radius of S17 is larger than that of S5.)

6. References

S1. A. B. Pangborn, M. A. Giardello, R. H. Grubbs, R. K. Rosen, Organometallics 15, 1518 (1996).

S2. N. A. Yakelis, R. G. Bergman, Organometallics 24, 3579 (2005). S3. A. Van der Bent, A. G. S. Blommaert, C. T. M. Melman, A. P. IJzerman, I. van

Wijngaarden, W. Soudijn, J. Med. Chem. 35, 1042 (1992). S4. F. M. Dixon, A. H. Eisenberg, J. R. Farrell, C. A. Mirkin, Organometallics 39, 3432

(2000). S5. D. A. Atwood, J. A. Jeiger, S. Liu, D. Rutherford, P. Wei, R. C. Tucker, Organometallics

18, 976 (1999). S6. K. Tortosa, C. Miola, T. Hamaide, J. Appl. Polym. Sci. 65, 2357 (1997). S7. B. J. Holliday, C. A. Mirkin, Angew. Chem., Int. Ed. 40, 2022 (2001). S8. N. C. Gianneschi, M. S. Masar, C. A. Mirkin, Acc. Chem. Res. 38, 825 (2005). S9. C. G. Oliveri, P. A. Ulmann, M. J. Wiester, C. A. Mirkin, Acc. Chem. Res. 41, 1618

(2008). S10. G. M. Sheldrick, SHELXTL Version 6.14; Bruker Analytical X-ray Instruments, Inc.:

Madison, WI, 2003. S11. Full-Matrix Least-Squares refinement on F2: wR2 = {Σ[w(Fo

2-Fc2)2]/Σ[w(Fo

2)2]}1/2 S12. GooF = S = {Σ[w(Fo

2-Fc2)2]/(n-p)}1/2 n = number of reflections; p = total number of

reflections refined. S13. D. T. Cromer, J. T. Waber, International Tables for X-ray Crystallography 1974, Vol. IV,

Table 2.2 A, The Kynoch Press, Birmingham, England. S14. J. A. Ibers, W. C. Hamilton, Acta Crystal. 17, 781 (1964). S15. D. C. Creagh, W. J. McAuley, International Tables for Crystallography 1992, Vol C,

Table 4.2.6.8, 219-222 (A.J.C. Wilson, ed.), Kluwer Academic Publishers, Boston. S16. D. C. Creagh, J. H. Hubbell, International Tables for Crystallography 1992, Vol C, Table

4.2.4.3, 200-206 (A.J.C. Wilson, ed.), Kluwer Academic Publishers, Boston. S17. HyperChem(TM), Hypercube, Inc., 1115 NW 4th Street, Gainesville, Florida 32601,

USA. S18. D. Wu, A. Chen, C. S. Johnson, Jr., J. Magn, Reson. A 115, 123 (1995). S19. A. Einstein, Investigations on the theory of Brownian movement; Dover: New York, 1956 S20. CRC Handbook of Chemistry and Physics, 47th ed.

  23

1H NMR of S2

 

  24

13C{1H} NMR of S2

  25

31P{1H} NMR of S2

  26

2D 1H COSY NMR of S4 in CD2Cl2

  27

31P{1H} NMR of S4

  28

2D 31P{1H} COSY NMR of S4 in CD2Cl2

  29

2D 1H COSY NMR of S5 in CD2Cl2

  30

2D 1H COSY NMR of S5 in CD2Cl2 (Aromatic region)

  31

2D 1H NOESY NMR of S5 in CD2Cl2

  32

2D 1H NOESY NMR of S5 in CD2Cl2 at room temperature (Aromatic region)

  33

Selective 1D 1H NOESY NMR of S5 in CD2Cl2 at 303.0 K

  34

31P {1H} NMR of S5

  35

2D 31P{1H} COSY NMR of S5 in CD2Cl2

  36

1H NMR of S10

  37

13C{1H} NMR of S10

  38

31P{1H} NMR of S10

  39

1H NMR of S14

  40

13C{1H} NMR of S14

  41

31P{1H} NMR of S14

  42

2D 1H COSY NMR of S15 in CD2Cl2

  43

31P{1H} NMR of S15 in CD2Cl2

  44

2D 31P{1H} COSY NMR of S15 in CD2Cl2

  45

2D 1H COSY NMR of S16 in CD2Cl2

  46

31P{1H} NMR of S16 in CD2Cl2

  47

2D 31P{1H} COSY NMR of S16 in toluene-d8

  48

2D 1H COSY NMR of S17 in CD2Cl2

  49

Selective 1D NOESY NMR of S17 in CD2Cl2 at 303.0 K (Negative peak is H of terminal methyl of AlOCH2CH3.)

  50

31P{1H} NMR of S17 in CD2Cl2

  51

2D 31P{1H} COSY NMR of S17 in CD2Cl2

  52

2D 1H COSY NMR of S18 in CD2Cl2

  53

31P{1H} NMR of S18 in CD2Cl2