Selective Reduction of Carboxylic acids to Aldehydes Catalyzed by B(C 6 F 5 ) 3

S1 Selective Reduction of Carboxylic acids to Aldehydes Catalyzed by B(C 6 F 5 ) 3 David Bézier, Sehoon Park and Maurice Brookhart* Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-32 E-mail: mbrookhart@unc.edu Supporting Information 1. General remarks S1-S2 2. General procedures for the selective reduction of carboxylic acids to aldehydes catalyzed by B(C 6 F 5 ) 3 S2-S3 3. Characterization data of acetals 2a and 2q S3 4. Characterization data of aldehydes S4-S9 5. 1 H NMR and 13 C{ 1 H} NMR spectra of acetals 2a and 2q S-S11 6. 1 H NMR and 13 C{ 1 H} NMR spectra of aldehydes S12-S32 General remarks All manipulations were carried out using standard Schlenk, high-vacuum, and glovebox techniques. Argon was purified by passing through columns of BASF R3-11 catalyst (Chemalog) and 4 Å molecular sieves. Benzene-d 6, toluene-d 8 and CD 2 Cl 2 (Cambridge Isotope Laboratories) were used without purification. All silanes were purchased from Aldrich and Gelest and stored under argon over 4 Å molecular sieves. All carboxylic acid substrates were purchased from commercial sources and usually used without further purification except for -decanoic acid, 9- undecynoic acid and 2-thiopheneacetic acid which were sublimed. Technical grade petroleum

S2 ether (- C bp.), ethyl acetate and dichloromethane were used for chromatography. B(C 6 F 5 ) 3 was purchased from Acros and Gelest and dried by mixing with Me 2 Si(Cl)H for 1 h followed by evaporation under vacuum. NMR spectra were recorded on Bruker spectrometers (DRX-, AVANCE- and AVANCE-). 1 H and 13 C NMR spectra were referenced to residual solvent peaks. General procedures for the selective reduction of carboxylic acids to aldehydes catalyzed by B(C 6 F 5 ) 3 From aliphatic carboxylic acids (procedure A): To a J. Young NMR tube was added RCO 2 H (.5 mmol), C 6 D 6 (.3 ml), and R' 3 SiH (1.15 mmol, 2.3 equiv) in a glovebox. A stock solution of B(C 6 F 5 ) 3 was previously prepared by dissolving 26 g (5 mmol) of B(C 6 F 5 ) 3 in 3 ml of C 6 D 6. From 15 µl (5 mol %) to µl (1 mol %) was added to the reaction mixture. (When 2 mol % of B(C 6 F 5 ) 3 was used, the powder was first added into the J. Young NMR tube). The reaction was initiated at 23 C and followed by 1 H NMR spectroscopy. At the end of the reaction, the crude reaction mixture was transferred from the NMR tube to a Schlenk flask and all volatiles (solvent + excess of silane) were removed under vacuum. A1: For substrates 1a, 1b, 1h, 1j, 1k, 1m, 1n: Following the above procedure, 2 ml of THF was added, followed by 2 ml of 1 M HCl(aq) with vigorous stirring. The reaction mixture was further stirred for 3 h at room temperature and was extracted with diethyl ether (3 ml). The combined organic layers were dried over anhydrous MgSO 4, filtered and concentrated under vacuum. The residue was then purified by silica gel column chromatography using an ethyl acetate/petroleum ether mixture (1/) to afford the desired product. A2: For substrates 1c, 1d, 1e, 1f, 1g, 1i, 1l, 1o (volatile or sensitive aldehydes) : Following the above procedure, the reaction mixture was diluted with 2.5 ml EtOH, and to the mixture was added under vigorous stirring Brady s reagent [.15 g of 2,4-dinitrophenylhydrazine (% H 2 O),.5 ml of concentrated H 2 SO 4,.75 ml of H 2 O, and 2.5 ml of EtOH]. 1 A yellow or orange precipitate was formed immediately. The solid was collected through filtration using a glass frits and washed with H 2 O. Pure product was obtained by recrystallization from EtOH. From aromatic carboxylic acids (procedure B, substrates 1q, 1r, 1t, 1u, 1v, 1w): To a J. Young NMR tube was added B(C 6 F 5 ) 3 (2 mol %, 52 g), RCO 2 H (.5 mmol), and Ph 3 SiH (1.25 1 M. Behforouz, J. L. Bolan, M. S. Flynt, J. Org. Chem. 1985,, 1186-1189.

S3 mmol, 2.5 equiv,.326 g), followed by CD 2 Cl 2 (.6 ml) in a glove box. The hydrosilylation reaction was conducted at 23 C and monitored by 1 H NMR spectroscopy. At the end of the reaction, the crude reaction mixture was filtered through a plug of silica gel with CH 2 Cl 2 as an eluent in order to remove B(C 6 F 5 ) 3 and the filtrate was evaporated. Then 2.5 ml of Et 2 O was added followed by.5 ml of trifluoroacetic acid (99%) with vigorous stirring. The reaction mixture was stirred for 1.5 hour at room temperature and 2.5 ml of Et 2 O was added. The reaction was stirred for another 1.5 h followed by addition of 4 ml of H 2 O and extracted with diethyl ether (3 ml). The combined organic layers were dried over anhydrous MgSO 4, filtered and concentrated under vacuum. The yield of the aldehyde was first determined by 1 H NMR of the crude mixture using EtOAc (.5 mmol, 49 µl) as an internal standard in CD 2 Cl 2. For the substrates 1r, 1t, 1u, the residue was then purified by silica gel column chromatography using a CH 2 Cl 2 / petroleum ether mixture (4/) to afford the desired product. For the substrate 1s: the procedure A1 was followed. (2a) Characterization data of acetals 2a and 2q From crude reaction mixture, before quenching: 1 H NMR ( MHz, C 6 D 6 ): δ 7.27-7.25 (m, 4H), 7.18-7.15 (m, 1H), 5.35 (t, J = 4.9, 1H), 2.89-2.85 (m, 2H), 5- (m, 2H), 1.12 (t, J =, 18H),.76 (q, J =, 12H). 13 C{ 1 H} NMR (1 MHz, CDCl 3 ): δ 142.47, 128.77, 128.73, 126.12, 93.19, 46, 31.39, 7.24 (6C), 5.91 (6C). (2q) From crude reaction mixture, before quenching: 1 H NMR ( MHz, CD 2 Cl 2 ): δ 7.64-7.62 (m, 12H), 7.59-7.55 (m, 6H), 7.47-7. (m, 17H), 6.47 (s, 1H). 13 C{ 1 H} NMR (1 MHz, CDCl 3 ): δ 143.49, 138 (6C), 134.49 (3C),.48 (4C), 128.93 (2C), 128.28 (6C), 126.53 (2C), 95.34.

S4 Characterization data for aldehydes Hydrocinnamaldehyde (5a) O H The compound was prepared as described using the procedure A1 (m = 58 mg, 86% isolated yield). 1 H NMR ( MHz, CDCl 3 ): δ 9.83 (t, J = 1.3, 1H), 7.32-7. (m, 2H), 7.24-7.21 (m, 3H), 2.97 (t, J = 7.6, 2H), 2.79 (td, J = 7.7, 1.3, 2H). 13 C{ 1 H} NMR (151 MHz, CDCl 3 ): δ 1.64,.42, 128.68, 128.37, 126.38, 45.35, 28.. Phenylacetaldehyde (5b) O H The compound was prepared as described using the procedure A1 (m = 43 mg, 71% isolated yield). 1 H NMR ( MHz, CDCl 3 ): δ 9.76 (t, J = 2.1, 1H), 7.-7.31 (m, 3H), 7.24-7.22 (m, 2H), 3. (d, J = 2.1, 2H). 13 C{ 1 H} NMR (1 MHz, CDCl 3 ): δ 199.58, 131.96, 129.75, 129.14, 127.55,.72. 1-(Propylidene)-2-(2,4-dinitrophenyl)hydrazine (5c) The compound was prepared as described using the procedure A2 (m = 89 mg, 75% isolated yield). 1 H NMR ( MHz, CDCl 3 ): δ 12 (s, 1H), 9.12 (d, J = 2.3, 1H), 8. (dd, J = 9.6, 2.3, 1H), 7.94 (d, J = 9.6, 1H), 7.57 (t, J = 4.8, 1H), 2.47 (qd, J = 7.5, 4.8, 2H), 1.22 (t, J = 7.5, 3H). 13 C{ 1 H} NMR (1 MHz, CDCl 3 ): δ 153., 145.34, 137.89,.9, 128.92, 123.65, 116.64, 26.17,.62. 1-(Hexylidene)-2-(2,4-dinitrophenyl)hydrazine (5d) The compound was prepared as described using the procedure A2 (m = 99 mg, 71% isolated yield). 1 H NMR ( MHz, CDCl 3 ): δ 12 (s, 1H), 9.12 (d, J = 2.5, 1H), 8. (dd, J = 9.6, 2.5, 1H), 7.93 (d, J = 9.6, 1H), 7.54 (t, J = 5.4, 1H), 2.43 (dt, J = 7.5, 5.6, 2H), 1.65-1. (m, 2H),1.39-1.37 (m, 4H),.93 (t, J = 6.9, 3H). 13 C{ 1 H} NMR (151 MHz, CDCl 3 ): δ 152.92, 145.27, 137.82,.7, 128.85, 123.63, 116.64, 32.61, 31.45, 26.12, 22.54, 18.

S5 Decanal (5e) The compound was prepared as described using the procedure A1 (m = 56 mg, 72% isolated yield). 1 H NMR ( MHz, CDCl 3 ): δ 9.75 (t, J = 1.7, 1H), 2. (dt, J = 1.7, 7.4, 2H), 1.67-1.58 (m, 2H), 1.29-1.25 (m, 12H),.87 (t, J = 6.8, 3H). 13 C{ 1 H} NMR (1 MHz, CDCl 3 ): δ 2.88, 44, 31.98, 29.49, 29.36, 29., 29.13, 22.77, 22.23, 14.18. 1-(2-Methylpropylidene)-2-(2,4-dinitrophenyl)hydrazine (5f) The compound was prepared as described using the procedure A2 (m = 5 mg, 83% isolated yield). 1 H NMR ( MHz, CDCl 3 ): δ.98 (s, 1H), 9. (d, J = 2.4, 1H), 8.28 (dd, J = 9.4, 2.1, 1H), 7.92 (d, J = 9.6, 1H), 7.48 (d, J = 4.8, 1H), 2.73-2.65 (m, 1H), 1.21 (t, J =, 6H). 13 C{ 1 H} NMR (151 MHz, CDCl 3 ): δ 157.35, 145.39, 137.82,.5, 128., 123.63, 116.67, 31.95, 19.73. 1-(Cyclohexylmethylene)-2-(2,4-dinitrophenyl)hydrazine (5g) The compound was prepared as described using the procedure A2 (m = 115 mg, 79% isolated yield). 1 H NMR ( MHz, CDCl 3 ): δ.97 (s, 1H), 9. (br.s, 1H), 8.28 (d, J = 8.9, 2.1, 1H), 7.91 (d, J = 9.5, 1H), 7.44 (d, J = 4.5, 1H), 2.41 (m, 1H), 1.92-1.91 (m, 2H), 1.81-1.71 (m, 3H), 1.37-1.24 (m, 5H). 13 C{ 1 H} NMR (151 MHz, CDCl 3 ): δ 156.52, 145.37, 137.78,.4, 128.87, 123.64, 116.67, 47,.16 (2C), 25.98, 25.53 (2C). 2-Phenylpropionaldehyde (5h) The compound was prepared as described using the procedure A1 (m = 53 mg, 79% isolated yield). 1 H NMR ( MHz, CDCl 3 ): δ 9. (d, J = 1.3, 1H), 7.41-7.37 (m, 2H), 7.33-7.29 (m, 1H), 7.23-7.21 (m, 2H), 3.64 (q, J = 7.2, 1H), 1.45 (d, J = 7.1, 3H). 13 C{ 1 H} NMR (1 MHz, CDCl 3 ): δ 1., 137.83, 129.19, 128.43, 127.63, 53.12, 14.72.

S6 1-(2,2-dimethylmethylpropylidene)-2-(2,4-dinitrophenyl)hydrazine (5i) The compound was prepared as described using the procedure A2 (m = 1 mg, 76% isolated yield). 1 H NMR ( MHz, CDCl 3 ): δ.95 (s, 1H), 9.12 (d, J = 2.3, 1H), 8. (dd, J = 9.5, 2.1, 1H), 7.92 (d, J = 9.6, 1H), 7.44 (s, 1H), 1.21 (s, 9H). 13 C{ 1 H} NMR (1 MHz, CDCl 3 ): δ 159.97, 145.48, 137.79,.2, 128.91, 123., 116.71, 35.69, 27.46 (3C). 1-Adamantane carbaldehyde (5j) The compound was prepared as described using the procedure A1 (m = 68 mg, 83% isolated yield). 1 H NMR ( MHz, CDCl 3 ): δ 9. (s, 1H), 6 (m, 3H), 1.78-1.67 (m, 12H). 13 C{ 1 H} NMR (1 MHz, CDCl 3 ): δ 6, 44.94, 36.68 (3C), 35.96 (3C), 27.48 (3C). (Z)-9-Octadecenal (5k) The compound was prepared as described using the procedure A1 (m = 127 mg, 95% isolated yield). 1 H NMR ( MHz, CDCl 3 ): δ 9.74 (t, J = 1.7, 1H), 5.36-5.28 (m, 2H), 2.39 (dt, J = 1.7, 7.4, 2H), -1.98 (m, 4H), 1.62-1.57 (m, 2H), 1.29-1.25 (m, H),.86 (t, J = 6.8, 3H). 13 C{ 1 H} NMR (1 MHz, CDCl 3 ): δ 2.85,., 129.76,, 31, 29.86, 29.76, 29.63, 29.43 (2C), 29.36, 29.24, 29.15, 27.31, 27.24, 22.78, 22.16, 14.. 1-(Hex-3-enylidene)-2-(2,4-dinitrophenyl)hydrazine (5l) The compound was prepared as described using the procedure A2 (m = mg, 65% isolated yield, containing 83% of 5l and 17% of the isomer 1-(hex-2-enylidene)-2-(2,4- dinitrophenyl)hydrazine). 5l : 1 H NMR ( MHz, CDCl 3 ): δ 14 (s, 1H), 9.12 (d, J = 2.4, 1H), 8. (dd, J = 9.5, 2.1, 1H), 7.94 (d, J = 9.6, 1H), 7.47 (t, J = 5.5, 1H), 5.67 (dt, J = 13.7, 6.3, 1H), 5.48 (dt, J = 13.7, 6.4, 1H), 3.13 (t, J = 5.6, 2H), 8 (dq, J = 13.7, 6.9, 2H), 1 (t, J =, 3H). 13 C{ 1 H} NMR (151 MHz, CDCl 3 ): δ 152, 145.26, 137.96, 136.76,., 128.97, 123.62, 121.98, 116.68, 35., 25.78, 13.68.

S7 9-Undecynal (5m) The compound was prepared as described using the procedure A1 (m = 76 mg, 91% isolated yield). 1 H NMR ( MHz, CDCl 3 ): δ 9.76 (t, J = 1.8, 1H), 2.42 (dt, J = 1.7, 7.4, 2H), 2.13-8 (m, 2H), 1.77 (t, J = 2.5, 3H), 1.66-1.59 (m, 2H), 1.-1.43 (m, 2H), 1.39-1. (m, 6H). 13 C{ 1 H} NMR (1 MHz, CDCl 3 ): δ 2., 79.28, 75.49, 43.95, 29.12, 23, 28.96, 28.69, 29, 18.75, 3.52. -Bromodecanal (5n) The compound was prepared as described using the procedure A1 (m = 5 mg, 89% isolated yield). 1 H NMR ( MHz, CDCl 3 ): δ 9.76 (t, J = 1.7, 1H), 3. (t, J = 6.8, 2H), 2.42 (dt, J = 1.7, 7.4, 2H), 1.88-1.81 (m, 2H), 1.64-1.61 (m, 2H), 1.44-1. (m, 2H), 1.-1.28 (m, 8H). 13 C{ 1 H} NMR (1 MHz, CDCl 3 ): δ 2.91, 43.95, 37, 32.85, 29., 29.27, 29.16, 28.73, 28.18, 22.11. 1-(2-Thiophen-2-yl)ethylidene)-2-(2,4-dinitrophenyl)hydrazine (5o) The compound was prepared as described using the procedure A2 due to light sensitivity of the pure aldehyde (m = 7 mg, % isolated yield). 1 H NMR ( MHz, CDCl 3 ): δ 18 (s, 1H), 9.12 (s, 1H), 8.33 (d, J =, 1H), 7.98 (d, J = 9.3, 1H), 7.61 (t, J = 4.6, 1H), 7.26 (s, 1H), 1-6.94 (m, 2H), 3.97 (d, J = 4.4, 2H). 13 C{ 1 H} NMR (1 MHz, CDCl 3 ): δ 148.95, 145.14, 138.14, 137.34,.7, 129.16, 127.44, 126., 125.25, 123.45, 116., 33.18. Benzaldehyde (5q) The compound was prepared as described using the procedure B. The yield was determined by 1 H NMR of the crude mixture using EtOAc as an internal standard (yield = 72%). 1 H NMR ( MHz, CD 2 Cl 2 ): δ 9.98 (s, 1H), 7.87 (d, J = 7.3, 2H), 7.61-7.57 (m, 3H).

S8 p-tolualdehyde (5r) The compound was prepared as described using the procedure B (m = 41 mg, 68% isolated yield). 1 H NMR ( MHz, CDCl 3 ): δ 9.93 (s, 1H), 7.74 (d, J = 8.1, 2H), 7.29 (d, J =, 2H), 2. (s, 3H). 13 C{ 1 H} NMR (1 MHz, CDCl 3 ): δ 191.97, 145.55, 134.23, 129.84, 129.72, 21.86. o-tolualdehyde (5s) The compound was prepared as described using the procedure A1 (m = 42 mg, 69% isolated yield). 1 H NMR ( MHz, CDCl 3 ): δ.27 (s, 1H), 7. (dd, J = 7.6, 1.3, 1H), 7.48 (dt, J = 7.5, 1.4, 1H), 7.36 (t, J = 7.5, 1H), 7.26 (d, J = 7.5, 1H), 2.68 (s, 3H). 13 C{ 1 H} NMR (1 MHz, CDCl 3 ): δ 192.91,.75, 134.33, 133.76, 132.18, 131.91, 126.46, 19.. Biphenyl-4-carboxaldehyde (5t) The compound was prepared as described using the procedure B (m = 68 mg, 75% isolated yield). 1 H NMR ( MHz, CDCl 3 ): δ 6 (s, 1H), 7.96 (d, J = 8.3, 2H), 7.76 (d, J = 8.2, 2H), 7.65-7.64 (m, 2H), 7.49 (t, J = 7.6, 2H), 7.43 (t, J = 7.4, 1H). 13 C{ 1 H} NMR (151 MHz, CDCl 3 ): δ 197, 147.32, 139.83, 135.31,., 129.14, 128., 127.81, 127.49. 4-Bromobenzaldehyde (5u) The compound was prepared as described using the procedure B (m = 66 mg, 72% isolated yield). 1 H NMR ( MHz, CDCl 3 ): δ 9.96 (s, 1H), 7.73 (d, J = 8.2, 2H), 7.67 (d, J = 8.2, 2H). 13 C{ 1 H} NMR (1 MHz, CDCl 3 ): δ 191.16, 135.18, 132.54, 137, 129.87. 4-Chlorobenzaldehyde (5v) The compound was prepared as described using the procedure B. The yield was determined by

1 H NMR of the crude mixture using EtOAc as an internal standard (yield = 87%). 1 H NMR ( MHz, CD 2 Cl 2 ): δ 9.94 (s, 1H), 7.86 (d, J = 7.3, 2H), 7.57 (d, J = 7.3, 2H). 4-(Trifluoromethyl)benzaldehyde (5w) S9 The compound was prepared as described using the procedure B. The yield was determined by 1 H NMR of the crude mixture using EtOAc as an internal standard (yield = 68%). 1 H NMR ( MHz, CD 2 Cl 2 ): δ 7 (s, 1H), 5 (d, J = 7.8, 2H), 7.87 (d, J = 7.8, 2H).

S 7.2 7.264 7.259 7.2 7.181 7.172 7.167 7.163 7.159 7.154 7. 7.145 5.365 5.353 5.341 2.892 2.873 2.867 2.852 52 39 32 26 13 1.141 1.122 1.2.788.768.748.728 1 * * * 1 1 1 142.465 128.772 128.727 126.122 93.187 464 31.385 7.244 5.914 * *

S11 7.643 7.627 7.623 7.589 7.585 7.584 7.567 7.552 7.549 7.545 7.472 7.468 7.463 7.454 7.435 7.423 7.416 7.415 7.399 7.395 6.472 1 4 * * * 143.487 1383 134.489.477 128.935 128.276 126.533 95.339 * * *

S12 1 H NMR and 13 C{ 1 H} NMR spectra of aldehydes 9.827 9.825 9.823 7.324 7.311 7.298 7.237 7.224 7.216 7.212 7.5 2.984 2.971 2.959 2.4 2.2 2.791 2.789 2.779 2.777 3 1 1.643.422 128.681 128.371 126.379 45.346 28.196 2 ppm (f1) 1 1 1 1 -

S13 ppm (f1) 1 9.762 9.757 9.751 7.398 7.3 7.362 7.3 7.312 7.237 7.219 3.698 3.693 1 2 ppm (f1) - 1 1 1 1 2 199.5 131.962 129.746 129.138 127.552.723

S14 1 118 9.126 9. 8.314 8.9 8.2 8.285 7.9 7.926 7.579 7.567 7.555 2.4 2.486 2.473 2.467 2.455 2.436 1.235 1.217 1.198 1 1 1 1 153.4 145.3 137.892.89 128.922 123.652 116.644 26.165.623

S15 1 9.125 9. 8.7 8.3 8.291 8.287 7.937 7.921 7.544 7.535 7.526 2.446 2.437 2.434 2.425 2.421 2.412 1.646 1.633 1.6 1.621 1.9 1.597 1.391 1.385 1.3 1.374 1.368.939.928.917 1 1 1 1 152.919 145.269 137.819.66 128.845 123.634 116.639 32.6 31.448 26.117 22.537 179

S16 1 9.751 9.747 9.743 2.422 2.417 2.3 2.399 2.385 2.381 1.666 1.648 1.631 1.613 1.595 1.577 1.286 1.254.881.865.847 12. ppm (f1) - 1 1 1 1 2 2.883 437 31.975 29.493 29.356 29.2 29.126 22.774 22.234 14.1

S17 1 1.975 9.3 99 8.293 8.2 8.277 8.274 7.928 7.912 7.486 7.478 2.728 2.717 2.6 2.695 2.686 2.675 2.664 2.653 1.211 1.199 6.19 1 1 1 1 157.348 145.3 137.817.54 128.896 123.6 116.672 31.952 19.733

S18 1 1.968 9.1 8.283 8.269 7.917 7.1 7.446 7.439 7.2 2.5 1.922 1.9 1.8 1.729 1.9 1.374 1.358 1.344 1.255 1.238 ppm (f1) 1 1 1 1 156.515 145.365 137.779.35 128.867 123.646 116.666 4.157 25.978 25.531

S19 ppm (f1) 1 1 9.697 9.694 7.8 7.4 7.391 7.371 7.332 7.329 7.315 7.311 7.5 7.295 7.292 7.234 7.2 7.225 7.213 3.6 3.653 3.635 3.617 1.463 1.446 1.12 1 ppm (f1) - 1 1 1 1 2 1.196 137.829 129.1 128.429 127.633 53.124 14.721

S 1 1.947 9.123 9.117 8.313 8.7 8.289 8.284 7.936 7.912 7.441 1.214 1 1 1 1 159.965 145.482 137.788.24 128.912 123.1 116.712 35.686 27.461

S21 1 9.1 57 1.784 1.754 1.712 1.6 1.666 12.19 2 ppm (f1) - 1 1 1 1 2 66 44.944 36.682 35.962 27.475

S22 1 1 9.7 9.736 9.732 5.363 5.349 5.336 5.326 5.321 5.318 5.313 5.4 5.291 5.276 2.414 2.4 2.396 2.392 2.377 2.373 1.997 1.983 1.624 1.6 1.588 1.5 1.288 1.247.875.859.841 1 4 4.29 1.35 2-1 1 1 1 2 2.8.2 129.763 43.995 313 29.864 29.763 29.631 29.427 29.3 29.238 29. 27.311 27.238 22.784 22.164 14.197

S23 1 1 137 9.125 9.121 8.314 8.311 8.298 8.295 7.947 7.931 7.4 7.471 7.462 5.697 5.687 5.674 5.672 5.661 5.651 5. 5.4 5.478 5.476 5.464 5.453 3. 3. 3.121 2.6 95 83 72 26 14 1 * * * * * H2O 1 1 1519 145.264 137.958 136.761.96 128.968 123.622 121.982 116.678 35.3 25.782 13.677 * * * * * *

S24 1 9.764 9.7 9.755 2.438 2.433 2.419 2.415 2.1 2.397 2. 2.124 2.119 2.113 2.7 2.1 96 89 83 1.779 1.772 1.766 1.663 1.645 1.628 1.6 1.591 1.495 1.4 1.461 1.443 1.426 1.4 1.386 1.372 1.363 1.351 1.335 1.326 1.318 1.311 8 1 1 6.13-1 1 1 1 2 2. 79.279 75.4 43.948 29.116 227 28.957 28.6 293 18.746 3.515

S25 9.767 9.762 9.758 3.419 3.2 3.385 2.4 2.436 2.422 2.417 2.3 2.399 1.882 1.865 1.847 1.828 1.811 1.642 1.624 1.6 1.435 1.418 1.1 1. 2 2 3 8.24-1 1 1 1 2 2.911 43.954 372 32.851 29.295 29.266 29.162 28.733 28.179 22.5

S26 1 1 178 9.118 8.337 8.315 7.983 7.9 7.5 7.2 7 6.941 3.973 3.962 1 1 1 1 148.945 145.143 138.135 137.335.73 129.161 127.441 126.395 125.248 123.453 116.699 33.184

S27 9.976 7.9 7.932 Et2O + EtOAc EtOAc Ph3SiOSiPh3 Et2O EtOAc Ph3SiH 4.18 2.81 2

S28 1 1 9.928 7.752 7.732 7.3 7.283 2.1 1 1 1 1 191.971 145.549 134.231 129.844 129.724 21.862

S29 1.274 7.9 7.5 7.789 7.786 7.497 7.494 7.478 7.475 7.4 7.456 7.379 7.361 7.342 7.271 7.252 2.675-1 1 1 1 2 192.8.747 134.328 133.763 132.1 131.9 126.461 19.699

S 1 63 7.966 7.952 7.767 7.753 7.652 7.6 7.638 7.2 7.489 7.476 7.437 7.425 7.413 1 1 1 1 19 147.318 139.8 135.5.1 129.144 128. 127.813 127.492

S31 9.961 7.743 7.722 7.677 7.657 191.156 135.179 132.5 1371 129.873 1 1 1 1

S32 9.935 7.868 7.848 7.577 7.558 Ph3SiOSiPh3 EtOAc Et2O + EtOAc EtOAC Et2O Ph3SiH 3.29 2.19 1.98 4 1 68 62 43 7.875 7.856 Et2O Et2O + EtOAc TFA Ph3SiOSiPh3 EtOAc EtOAc 4.42 2.96 1 1