Ring-Opening / Fragmentation of Dihydropyrones for the Synthesis of Homopropargyl Alcohols

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Ring-pening / Fragmentation of Dihydropyrones for the Synthesis of Homopropargyl Alcohols Jumreang Tummatorn, and Gregory B. Dudley, * Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306 4390. Department of Chemistry, Faculty of Science, Chulalongkorn University, Phyathai Road, Bangkok 10330, Thailand Supporting Information CNTENTS: General information General experimental procedures Synthesis of DHP triflates 1 o Typical procedure for the synthesis of pyran-2,4-diones o Typical procedure for the preparation of DHP triflates S2 S2 S2 S3 Synthesis of HPAs 2 S3 o General procedure for the carbanion-triggered fragmentation of DHP triflates S3 Characterization (analytical) data Analytical data of DHP triflates (1a-1n) Analytical data of homopropargyl alcohols (2a-2n) Copies of 1 H and 13 C- NMR spectra for compound 1 H and 13 C- NMR spectra of (1a-1n) 1 H and 13 C- NMR spectra of (2a-2n) S4-S8 S8-S12 S13-S40 S41-S68 S1

General information 1 H-NMR and 13 C-NMR spectra were recorded on a 300 MHz spectrometer using CDCl 3 as the deuterated solvent. The chemical shifts (δ) are reported in parts per million (ppm) relative to the residual CHCl 3 peak (7.26 ppm for 1 H-NMR and 77.0 ppm for 13 C-NMR). The coupling constants (J) are reported in Hertz (Hz). IR spectra were recorded on an FTIR spectrometer on NaCl discs. Mass spectra were recorded using electrospray ionization (ESI) or chemical ionization (CI). Yields refer to isolated material judged to be 95% pure by 1 H NMR spectroscopy following silica gel chromatography. All the chemicals were used as received unless otherwise stated. The purifications were performed by flash chromatography using silica gel F-254 (230-499 mesh particle size). General experimental procedures 1) Synthesis of DHP triflates 1 R 2 1) NaH, THF, 0 C 2) BuLi, 0 C R 2 Tf 2, NEt 3 R 2 CH 3 R 1 R 4 3) CH 2 Cl 2, -78 C R 4 R 3 R 4 R 3 Tf R 1 R 3 R 1 5 4) aq. NaH 6 1 pyran-2,4 dione DHP triflate 42-93 % 73-98 % 1.1) Typical procedure for the synthesis of pyran-2,4-diones 1 To a solution of NaH (60% in paraffin oil; 1.28 g, 32 mmol) in THF (80 ml) at 0 ºC was added ethyl acetoacetate (5, R 1 =R 2 =H, 1.72 ml, 16.0 mmol) dropwise under argon. The mixture was stirred for 30 min and then n-buli (1.5 M in hexane, 21.3 ml, 32.0 mmol) was added dropwise. After stirring for 15 min, benzaldehyde (1.63 ml, 16.0 mmol) was added dropwise at 0 ºC and stirring continued for 30 min. The reaction mixture was then poured into 2 M NaH (50 ml) and stirred at room temperature for 5 h. The reaction mixture was partitioned between Et 2 and water, and the aqueous phase was extracted with two additional portions of Et 2. The 1 Adapted from: de Souza, L. C.; dos Santos, A. F.; Goulart Sant A. E.; de liveira Imbroisi, D. Bioorg. Med. Chem. 2004, 12, 865 869. S2

aqueous phase was cooled with ice and acidified to ph 6 with 6 M HCl. The resulting mixture was extracted with EtAc (3x50 ml). The combined extracts were washed with water (2x100 ml) and brine (2x50 ml), dried over MgS 4, and concentrated under reduced pressure. Recrystallization from CHCl 3 provided 6-phenyldihydropyran-2,4-dione (6, R 1 =R 2 =R 4 =H, R 3 =Ph) (3.00 g, 58% yield). 1.2) Typical procedure for the preparation of DHP triflates To a CH 2 Cl 2 solution (20 ml) of 6-phenylpyran-2,4-dione (6, R 1 =R 2 =R 4 =H, R 3 =Ph) (761 mg, 4.0 mmol) and triethylamine (0.60 ml, 4.3 mmol) was added Tf 2 (0.740 ml, 4.4 mmol) at 78 ºC under Argon. The reaction mixture was stirred for 30 min at 78 ºC and then quenched with water and extracted with CH 2 Cl 2. The combined organic layers were dried over MgS 4 and concentrated under reduced pressure. The crude product was purified by chromatography on a silica gel (elution with 20% EtAc in hexanes) to yield trifluoromethanesulfonic acid 6-oxo-2-phenyl-3,6- dihydro-2h-pyran-4-yl ester (1a, R 1 =R 2 =R 4 =H, R 3 =Ph) (1.24 g, 96%). 2) Synthesis of HPAs 2 R 1 Tf Tf M Tf M R 1 MeMgBr (2.0 equiv) R 1 R 4 R 1 R 4 R 4 toluene, 78 to 60 C R 2 R3 M R 2 R3 R 2 R3 R R 1 R 2 R 2 H R 4 R 3 2.1) General procedure for the carbanion-triggered fragmentation of DHP triflates (1 2, Tables 2 and 3). Methylmagnesium bromide (2 equiv) is added dropwise over 10 min to a solution of DHP triflate 1 (1.0 equiv) in toluene (10 ml/mmol) at 78 ºC. The reaction mixture is warmed to room temperature and stirred for 1 h while monitoring conversion of the reaction from DHP triflate 1 to an intermediate and then to HPA 2 by TLC analysis. If formation of 2 is incomplete after 1 h at room temperature, then the mixture is heated at 60 ºC to achieve full conversion. The reaction mixture is allowed to cool, quenched with saturated aqueous NH 4 Cl, and extracted with ether. The combined organic layers are washed with water and brine, dried over MgS 4, filtered, concentrated under vacuum, and purified on silica gel to yield homopropagyl alcohol 2. S3

Analytical (characterization) data Analytical data of DHP triflates (1a-1n) Ph Tf Trifluoro-methanesulfonic acid 6-oxo-2-phenyl-3,6-dihydro-2Hpyran-4-yl ester (1a) white solid, 1.24 g (96% from 6; 56% overall yield from 5); 1 H-NMR (300 MHz, CDCl 3 ) δ 7.42 (m, 5H), 6.18 (d, 1H, J = 2.3 Hz), 5.55 (dd, 1H, J = 11.7, 4.1 Hz), 3.10 (ddd, 1H, J = 18.0, 11.7, 2.3 Hz), 2.86 (dd, 1H, J = 18.0, 4.1 Hz); 13 C-NMR (300 MHz, CDCl 3 ) δ 162.6, 161.4, 136.3, 129.2, 128.9, 125.9, 118.3 (q, 1 J CF = 321 Hz, C-F), 110.0, 77.7, 34.4. IR (neat) 1732, 1660, 1497, 1433, 1220, 1137, 901 cm -1 ; HRMS (CI+) m/z: (M+H) + Calcd for C 12 H 10 F 3 5 S: 323.0201, found: 323.0196. Tf Br Trifluoro-methanesulfonic acid 2-(4-bromo-phenyl)-6-oxo- 3,6-dihydro-2H-pyran-4-yl ester (1b) white solid, 430 mg (98% from 6; 60% overall yield from 5); 1 H NMR (300 MHz, CDCl 3 ) δ ppm 7.56 (d, 2H, J = 7.6 Hz), 7.29 (d, 2H, J = 7.6 Hz), 6.16 (d, 1H, J = 2.3 Hz), 5.51 (dd, 1H, J = 11.7, 4.1 Hz), 3.05 (ddd, 1H, J = 18.0, 11.7, 2.3 Hz), 2.85 (dd, 1H, J = 18.0, 4.1 Hz); 13 C-NMR (300 MHz, CDCl 3 ) δ 162.3, 161.1, 135.4, 132.2, 127.6, 123.5, 118.3 (q, 1 J CF = 321 Hz, C-F), 110.1, 77.0, 34.5. IR (neat) 1778, 1660, 1595, 1433, 1224, 1137, 902 cm -1 ; HRMS (CI+) m/z: (M+H) + Calcd for C 12 H 9 BrF 3 5 S: 400.9306, found: 400.9303. Tf H 3 C Trifluoro-methanesulfonic acid 2-(4-methoxy-phenyl)-6- oxo-3,6-dihydro-2h-pyran-4-yl ester (1c) white solid, 447 mg (90% from 6; 68% overall yield from 5); 1 H-NMR (300 MHz, CDCl 3 ) δ ppm 7.42-7.27 (m, 2H), 6.93 (m, 2H), 6.16 (d, 1H, J = 2.4 Hz,) 5.49 (dd,, 1H, J = 11.8, 4.0 Hz), 3.89-3.77 (s, 3H), 3.11 (ddd, 1H, J = 18.0, 11.8, 2.4 Hz), 2.82 (dd, 1H, J = 18.0, 4.0 Hz); 13 C-NMR (300 MHz, CDCl 3 ) δ 162.8, 161.5, 160.4, 128.3, 127.6, 118.3 (q, 1 J CF = 321 Hz, C-F), 114.3, 110.2, 77.7, 55.4, 34.5. IR (neat) 1730, 1661, 1517, 1426, 1215, 1136, 899 cm -1 ; HRMS (CI+) m/z: (M+H) + Calcd for C 13 H 12 F 3 6 S: 353.0307, found: 353.0301. S4

Tf Trifluoro-methanesulfonic acid 2-furan-2-yl-6-oxo-3,6-dihydro- 2H-pyran-4-yl ester (1d) yellow oil, 842 mg (87% from 6; 55% overall yield 5); 1 H-NMR (300 MHz, CDCl 3 ) δ 7.45 (d, 1H, J = 1.8 Hz), 6.49 (d, 1H, J = 3.3 Hz), 6.40 (dd, 1H, J = 3.3, 1.8 Hz), 6.13 (d, 1H, J = 1.8 Hz), 5.59 (dd, 1H, J = 10.1, 4.6 Hz), 3.33 (ddd, 1H, J = 18.1, 10.1, 1.8 Hz), 2.93 (dd, 1H, J = 18.1, 4.6 Hz); 13 C-NMR (300 MHz, CDCl 3 ) δ 162.0, 161.0, 148.4, 143.7, 118.3 (q, 1 J CF = 321 Hz, C-F), 110.7, 110.1, 110.0, 71.7, 30.7. IR (neat) 1738, 1666, 1555, 1415, 1145, 929 cm -1 ; MS (CI+) m/z: (M+H) + Calcd for C 10 H 8 F 3 6 S: 313.0, found: 313.0. Tf Trifluoro-methanesulfonic acid 6-oxo-2-styryl-3,6-dihydro- 2H-pyran-4-yl ester (1e) brown solid, 515 mg (73% from 6; 69% overall yield from 5); 1 H-NMR (300 MHz, CDCl 3 ) δ ppm 7.44-7.27 (m, 5H), 6.79 (d, 1H, J = 16.0 Hz), 6.24 (dd, 1H, J = 16.0, 6.4 Hz), 6.13 (d, 1H, J = 1.8 Hz), 5.27-5.15 (m, 1H), 3.02-2.80 (m, 2H); 13 C- NMR (300 MHz, CDCl3) δ 161.5, 161.11, 135.0, 134.7, 134.7, 128.7, 126.7, 123.4, 118.3 (q, 1 J CF = 321 Hz, C-F), 110.0, 76.5, 32.7. IR (neat) 1732, 1660, 1432, 1219, 1136, 901 cm -1 ; HRMS (CI+) m/z: (M+H) + Calcd for C 14 H 12 F 3 5 S: 349.0358, found: 349.0348 Tf Trifluoro-methanesulfonic acid 6-oxo-2-phenethyl-3,6- dihydro-2h-pyran-4-yl ester (1f) colorless oil, 1.30 g (76% from 6; 32% overall yield from 5); ; 1 H-NMR (300 MHz, CDCl 3 ) δ ppm 7.36-7.17 (m, 5H), 6.06 (d, 1H, J = 2.3 Hz), 4.49 (m, 1H), 2.96-2.71 (m, 3H), 2.58 (dd, 1H, J = 17.9, 4.1 Hz), 2.26-2.14 (m, 1H), 2.07-1.92 (m, 1H); 13 C-NMR (300 MHz, CDCl 3 ) δ 162.8, 161.5, 140.0, 128.6, 128.3, 126.4, 118.3 (q, 1 J CF = 321 Hz, C-F), 109.8, 75.4, 35.9, 32.4, 31.7. IR (neat) 2932, 1734, 1662, 1613, 1517, 1430, 1217, 1137, 1085, 900 cm -1 ; HRMS (CI+) m/z: (M+H) + Calcd for C 14 H 14 F 3 5 S: 351.0514, found: 351.0509. S5

Tf Trifluoro-methanesulfonic acid 2-cyclohexyl-6-oxo-3,6-dihydro- 2H-pyran-4-yl ester (1g) yellow solid, 1.05 g (89% from compound 6; 49% overall yield from 5); 1 H-NMR (300 MHz, CDCl 3 ) δ ppm 6.04 (d, 1H, J = 2.30 Hz), 4.40-4.19 (m, 1H), 2.81 (ddd, 1H, J = 17.8, 12.2, 1.2 Hz,), 2.53 (dd, 1H, J = 17.8, 3.9 Hz), 1.96 (m, 1H), 1.82-1.69 (m, 5H), 1.31-1.05 (m, 5H); 13 C-NMR (300 MHz, CDCl 3 ) δ 163.1, 162.1, 120.4, 109.8, 80.6, 41.2, 29.9, 28.0, 27.9, 26.0, 25.6, 25.5. IR (neat) 2930, 2856, 1731, 1665, 1427, 1220, 1137, 901 cm -1 ; HRMS (CI+) m/z: (M+H) + Calcd for C 12 H 16 F 3 5 S: 329.0671, found: 329.0668. Tf Trifluoro-methanesulfonic acid 2-tert-butyl-6-oxo-3,6-dihydro-2Hpyran-4-yl ester (1h) colorless oil, 1.41 g (80% from 6; 53% overall yield from 5); 1 H-NMR (300 MHz, CDCl 3 ) δ ppm 6.04 (d, 1H, J = 2.5 Hz,), 4.23-4.08 (m, 1H), 2.89-2.67 (m, 1H), 2.51-2.48 (m, 1H), 1.01 (s, 9H); 13 C- NMR (300 MHz, CDCl 3 ) δ 163.2, 162.4, 118.3 (q, 1 J CF = 321 Hz, C-F), 109.6, 83.9, 33.9, 28.2, 25.2 IR (neat) 2967, 1731, 1664, 1481, 1433, 1217, 1138, 901 cm -1 ; HRMS (CI+) m/z: (M+H) + Calcd for C 10 H 14 F 3 5 S: 303.0514, found: 303.0506. Tf Trifluoro-methanesulfonic acid 2-methyl-6-oxo-2- phenethyl-3,6-dihydro-2h-pyran-4-yl ester (1i) colorless oil, 332 mg (84% from 6; 63% overall yield from 5); 1 H-NMR (300 MHz, CDCl 3 ) δ ppm 7.31-7.24 (m, 2H), 7.23-7.11 (m, 3H), 6.08 (s, 1H), 2.87 (dd, 1H, J = 18.1, 1.7 Hz), 2.81-2.68 (m, 2H), 2.61 (d, 1H, J = 18.1 Hz), 2.13-2.00 (m, 2H), 1.54 (s, 3H); 13 C-NMR (300 MHz, CDCl 3 ) δ 162.2, 161.6, 140.4, 128.5, 128.1, 126.2, 118.2 (q, 1 J CF = 321 Hz, C-F), 109.7, 81.4, 42.2, 36.8, 29.7, 24.8. IR (neat) 1718, 1433, 1220, 1136, 1074, 907 cm -1 ; HRMS (CI+) m/z: (M+H) + Calcd for C 15 H 16 F 3 5 S: 365.0670, found: 365.0673. CH 3 Tf Trifluoro-methanesulfonic acid 5-methyl-6-oxo-2-phenyl-3,6- dihydro-2h-pyran-4-yl ester (1j) yellow solid, 311 mg (94% from 6; 67% overall yield from 5); 1 H-NMR (300 MHz, CDCl 3 ) δ ppm 7.41 (bs, 5H), 5.50 (dd, 1H, J = 11.9, 3.9 Hz), 3.15 (m, 1H), 2.90 (dd, 1H, J = 17.6, 3.0 Hz), 2.06 (s, 3H); 13 C-NMR (300 MHz, CDCl 3 ) δ 164.4, 155.2, 136.6, 129.2, S6

128.9, 126.0, 120.6, 118.2 (q, 1 J CF = 320 Hz, C-F), 77.2, 34.8, 10.8. IR (neat) 1716, 1687, 1410, 1230, 1138, 1060, 902 cm -1 ; HRMS (CI+) m/z: (M+H) + Calcd for C 13 H 12 F 3 5 S: 337.0358, found: 337.0354. Bn Tf Trifluoro-methanesulfonic acid 5-benzyl-6-oxo-2-phenyl-3,6- dihydro-2h-pyran-4-yl ester (1k) white solid, 346 mg (95% from 6; 56% overall yield from 5); 1 H-NMR (300 MHz, CDCl 3 ) δ ppm 7.32 (m, 10H), 5.46 (dd, 1H, J = 11.6, 4.0 Hz), 3.85 (s, 2H), 3.21 (dd, 1H, J = 17.8, 11.6 Hz,), 2.97 (dd, 1H, J = 17.8, 4.0 Hz); 13 C- NMR (300 MHz, CDCl 3 ) δ 163.8, 155.2, 136.8, 136.5, 129.2, 128.9, 128.8, 128.7, 127.0, 126.0, 123.8, 118.3 (q, 1 J CF = 321 Hz, C-F), 78.0, 34.7, 30.6. IR (neat) 1732, 1677, 1603, 1495, 1427, 1135, 911, 872, 792 cm -1 ; HRMS (CI+) m/z: (M+H) + Calcd for C 19 H 16 F 3 5 S: 413.0671, found: 413.0675. Tf CH 3 syn-trifluoro-methanesulfonic acid 2-cyclohexyl-3-methyl-6- oxo-3,6-dihydro-2h-pyran-4-yl ester (1l) colorless crystal, 653 mg (73% from 6; 25% overall yield 2 from 5); 1 H-NMR (300 MHz, CDCl 3 ) δ ppm 6.03 (s, 1H), 4.09 (dd, 1H, J = 10.3, 3.0 Hz,), 2.60 (dq, 1H, J = 7.0, 3.0 Hz), 2.32-2.18 (m, 1H), 1.86-1.50 (m, 5H), 1.39-1.09 (m, 6H), 1.09-0.85 (m, 2H); 13 C- NMR (300 MHz, CDCl 3 ) δ 168.0, 163.2, 118.3 (q, 1 J CF = 321 Hz, C-F), 108.1, 83.2, 37.4, 34.4, 29.3, 27.6, 26.1, 25.4, 25.1, 9.9. IR (neat) 2933, 1734, 1654, 1430, 1244, 1138, 912 cm -1 ; HRMS (CI+) m/z: (M+H) + Calcd for C 13 H 18 F 3 5 S: 343.0827, found: 343.0829. Tf CH 3 anti-trifluoro-methanesulfonic acid 2-cyclohexyl-3-methyl-6- oxo-3,6-dihydro-2h-pyran-4-yl ester (1m) colorless crystal, 797 mg (76% from 6; 21% overall yield 2 from 5); 1 H-NMR (300 MHz, CDCl 3 ) δ ppm 6.01 (s, 1H), 4.00 (t, 1H, J = 5.8 Hz), 2.94-2.79 (m, 1H), 1.85-1.53 (m, 6H), 1.37-1.07 (m, 8H); 13 C- NMR (300 MHz, CDCl 3 ) δ 165.3, 162.4, 118.3 (q, 1 J CF = 321 Hz, C-F), 108.8, 86.5, 39.4, 33.3, 29.7, 26.9, 25.9, 25.6, 14.7. IR (neat) 2 xanedione 5 prepared as a mixture of cis- and trans-diastereomers, which were separated by chromatography prior to formation of the DHP triflates 1l and 1m. S7

2931, 1738, 1655, 1430, 1218, 1138, 912 cm -1 ; HRMS (CI+) m/z: (M+H) + Calcd for C 13 H 18 F 3 5 S: 343.0827, found: 343.0826. Tf Trifluoro-methanesulfonic acid 3-benzyl-6-oxo-2-phenyl-3,6- dihydro-2h-pyran-4-yl ester (1n) white solid, 429 mg (81% from 6; 19% overall yield from 5, anti/syn 19:1); 1 H-NMR (300 MHz, CDCl 3 ) δ ppm 7.42-7.17 (m, 8H), 7.09-7.01 (m, 2H), 6.09 (s, 1H), 5.42 (d, 1H, J = 1.4 Hz), 3.22-3.12 (m, 2H), 2.95 (dd, 1H, J= 15.0, 10.8 Hz); 13 C- NMR (300 MHz, CDCl 3 ) δ 163.2, 162.4, 137.2, 136.1, 129.4, 129.3, 129.1, 129.0, 127.9, 125.6, 118.1 (q, 1 J CF = 321 Hz, C-F), 109.2, 78.9, 45.5, 36.8. IR (neat) 1738, 1654, 1497, 1432, 1221, 1136, 902 cm -1 ; HRMS (CI+) m/z: (M+H) + Calcd for C 19 H 16 F 3 5 S: 413.0670, found: 413.0676. S8

Analytical data of homopropargyl alcohols (2a-2n) H 1-Phenyl-but-3-yn-1-ol (2a) colorless oil, 46 mg (quantitative); 1 H- NMR (300 MHz, CDCl 3 ) δ 7.43-7.27 (m, 5H), 4.87 (dt, 1H, J = 6.3, 3.4 Hz), 2.65 (dd, 2H, J = 6.3, 2.6 Hz), 2.48 (d, 1H, J = 3.4 Hz), 2.08 (t, 1H, J = 2.6 Hz); 13 C-NMR (300 MHz, CDCl 3 ) δ 142.4, 128.4, 128.0, 125.7, 80.6, 72.3, 70.9, 29.4. IR (neat) 3370, 3296, 2911, 2119, 1453, 1214, 1055 cm -1 ; MS (CI+) m/z: (M H) + Calcd for C 10 H 9 : 129.1, found: 129.1. (Previous report and characterization data: Lee, A.S.; Chu, S.; Chang, Y.; Wang, S. Tetrahedron Lett. 2004, 45, 1551-1533). H Br 1-(4-Bromo-phenyl)-but-3-yn-1-ol (2b) colorless oil, 77 mg (99%); 1 H-NMR (300 MHz, CDCl 3 ) δ 7.41 (d, 2H, J = 8.4 Hz), 7.19 (d, 2H, J = 8.4 Hz), 4.75 (m, 1H), 2.59-2.49 (m, 2H), 2.43 (d, 1H, J = 3.6 Hz), 2.00 (t, 1H, J = 2.6 Hz); 13 C-NMR (300 MHz, CDCl 3 ) δ 141.3, 131.5, 127.5, 121.8, 80.1, 71.6, 71.3, 29.4. IR (neat) 3372, 3295, 2910, 2118, 1486 cm -1 ; MS (CI+) m/z: (M+H) + Calcd for C 10 H 10 Br: 225.0, found: 225.0. (Previous report and characterization data: Banerjee, M.; Roy, S. rg. Lett. 2004, 6, 2137-2140). H H 3 C 1-(4-Methoxy-phenyl)-but-3-yn-1-ol (2c) colorless oil, 61 mg (95%); 1 H-NMR (300 MHz, CDCl 3 ) δ 7.30 (m, 2H), 6.88 (m, 2H), 4.82 (m, 1H), 3.80 (s, 3H), 2.65-2.57 (m, 2H), 2.42 (d, 1H, J = 3.2 Hz), 2.06 (t, 1H, J = 2.6 Hz); 13 C-NMR (300 MHz, CDCl 3 ) δ 159.2, 134.6, 127.0, 113.8, 80.7, 71.9, 70.8, 55.2, 29.3. IR (neat) 3468, 3289, 2910, 2118, 1610, 1512, 1247, 1031 cm -1 ; MS (CI+) m/z: (M+H) + Calcd for C 11 H 13 2 : 177.1, found: 177.1. (Previous report and characterization data: Lee, A.S.; Chu, S.; Chang, Y.; Wang, S. Tetrahedron Lett. 2004, 45, 1551-1533). H 1-Furan-2-yl-but-3-yn-1-ol (2d) yellow oil, 50 mg (92%); 1 H-NMR (300 MHz, CDCl 3 ) δ 7.39 (t, 1H, J = 1.2 Hz), 6.35 (m, 2H), 4.88 (m, 1H), 2.77 (dd, 2H, J = 6.3, 2.6 Hz), 2.46 (d, 1H, J = 5.4 Hz,), 2.07 (t, 1H, J = 2.6 Hz); 13 C-NMR (300 MHz, CDCl 3 ) δ 154.5, 142.3, 110.2, 106.6, 79.8, 71.1, 66.0, 26.0. IR (neat) 3290, 2917, 2119, 1015, 637 cm -1 ; MS (CI+) m/z: (M+H) + Calcd for S9

C 8 H 9 2 : 137.1, found: 137.1. (Previous report and characterization data: Lee, A.S.; Chu, S.; Chang, Y.; Wang, S. Tetrahedron Lett. 2004, 45, 1551-1533). H 1-Phenyl-hex-1-en-5-yn-3-ol (2e) colorless oil, 42 mg (84%); 1 H- NMR (300 MHz, CDCl 3 ) δ 7.32-7.09 (m, 5H), 6.54 (d, 1H, J = 15.9 Hz), 6.16 (dd, 1H, J = 15.9 Hz), 4.43-4.28 (m, 1H), 2.54-2.33 (m, 2H), 2.03 (m, 1H), 1.97 (t, 1H, J = 2.62 Hz); 13 C-NMR (300 MHz, CDCl 3 ) δ 136.3, 131.3, 129.9, 128.6, 127.9, 126.6, 80.2, 71.1, 71.7, 27.7. IR (neat) 3320, 3292, 2110, 1040, 749 cm - 1 ; MS (CI+) m/z: (M H) + Calcd for C 12 H 12 : 155.1, found: 155.1. (Previous report and characterization data: Banerjee, M.; Roy, S. rg. Lett. 2004, 6, 2137-2140). H 1-Phenyl-hex-5-yn-3-ol (2f) colorless oil, 56 mg (quantitative); 1 H-NMR (300 MHz, CDCl 3 ) δ 7.38-7.19 (m, 5H), 3.89-3.74 (m, 1H), 2.92-2.67 (m, 3H), 2.54-2.32 (m, 2H), 2.10 (t, 1H, J = 2.6 Hz), 1.96-1.85 (m, 2H); 13 C-NMR (300 MHz, CDCl 3 ) δ 141.6, 128.4, 125.9, 80.6, 71.0, 69.0, 37.7, 31.8, 27.4. IR (neat) 3345, 3296, 2934, 2117, 1453, 1052, 636 cm -1 ; MS (CI+) m/z: (M+H) + Calcd for C 12 H 15 : 175.1, found: 175.1. (Previous report and characterization data: Konishi, S.; Hanawa, H.; Maruoka, K. Tetrahedron: Asymmetry 2003, 14, 1603-1605.) H 1-Cyclohexyl-but-3-yn-1-ol (2g) colorless oil, 97 mg (85%); 1 H- NMR (300 MHz, CDCl 3 ) δ 3.56-3.43 (m, 1H), 2.51-2.26 (m, 2H), 2.04 (t, 1H, J = 2.6 Hz), 1.96 (d, 1H, J = 4.9 Hz,), 1.89 (d, 1H, J = 12.7 Hz), 1.82-1.70 (m, 2H), 1.70-1.58 (m, 2H), 1.46 (m, 1H), 1.34-0.92 (m, 5H); 13 C-NMR (300 MHz, CDCl 3 ) δ 81.3, 74.0, 70.6, 42.4, 29.0, 28.1, 26.3, 26.1, 25.9, 24.6. IR (neat) 3382, 3308, 2924, 2115, 1449, 1036 cm -1 ; MS (CI+) m/z: (M+H) + Calcd for C 10 H 17 : 153.1280, found: 153.1290. (Previous report and characterization data: Schneider, U.; Sugiura, M.; Kobayashi, S. Tetrahedron 2006, 62, 496-502.) H 2,2-Dimethyl-hex-5-yn-3-ol (2h) colorless oil, 91 mg (91%); 1 H-NMR (300 MHz, CDCl 3 ) δ 3.44 (td, 1H, J = 10.0, 3.2 Hz,), 2.42 (td, 1H, J = 16.6, 2.6 Hz), 2.23 (ddd, 1H, J = 16.6, 10.0, 2.6 Hz,), 2.10 (d, 1H, J = 3.2 Hz,), 2.04 (t, 1H, J = 2.6 Hz), 0.90 (s, 9H) ; 13 C-NMR (300 MHz, CDCl 3 ) δ 82.4, 77.4, 70.4, S10

34.6, 25.6, 22.6. IR (neat) 3317, 3283, 2954, 1376, 1077 cm -1 ; MS (CI+) m/z: (M+H) + Calcd for C 8 H 15 : 127.1, found: 127.1. (Previous report and characterization data: Kurono, N.; Sugita, K.; Tokuda, M. Tetrahedron 2000, 56, 847-854.) H 3-Methyl-1-phenyl-hex-5-yn-3-ol (2i) colorless oil, 58 mg (82%); 1 H-NMR (300 MHz, CDCl 3 ) δ 7.39-7.17 (m, 5H), 2.84-2.66 (m, 2H), 2.47 (d, 2H, J = 2.6 Hz), 2.14 (t, 1H, J = 2.6 Hz), 2.04-1.83 (m, 3H), 1.39 (s, 3H); 13 C-NMR (300 MHz, CDCl 3 ) δ 142.1, 128.4, 128.3, 125.8, 80.6, 71.5, 71.4, 42.9, 32.5, 30.3, 26.3. IR (neat) 3414, 3295, 2932, 2116, 1454, 1100, 699 cm -1 (Previous report and characterization data: Lee, P.; Kim, H.; Lee, K. Adv. Synth. Catal. 2005, 347, 1219-1222.) H CH 3 1-Phenyl-pent-3-yn-1-ol (2j) colorless oil, 49 mg (quantitative); 1 H-NMR (300 MHz, CDCl 3 ) δ 7.29-7.14 (m, 5H), 4.70 (m, 1H), 2.51-2.40 (m, 2H), 2.38-2.30 (m, 1H), 1.69 (t, 3H, J = 8.3 Hz); 13 C-NMR (300 MHz, CDCl 3 ) δ 142.8, 128.3, 127.7, 125.7, 78.6, 75.2, 72.6, 30.0, 3.5. IR (neat) 3389, 2917, 2114, 1453, 1047, 755 cm -1 ; MS (CI+) m/z: (M H) + Calcd for C 11 H 11 : 143.1, found: 143.1. (Previous report and characterization data: Kwon, J.S.; Pae, A. N.; Choi, K.I.; Koh, H.Y.; Kim, Y., Cho, Y.S. Tetrahedron Lett. 2001, 42, 1957-1959.) H Bn 1,5-Diphenyl-pent-3-yn-1-ol (2k) yellow oil, 79 mg (92%); 1 H- NMR (300 MHz, CDCl 3 ) δ ppm 7.38-7.20 (m, 10H), 4.83 (t, 1H, J = 6.3 Hz,), 3.56 (s, 2H), 2.68-2.64 (m, 2H); 13 C-NMR (300 MHz, CDCl 3 ) δ 142.7, 136.9, 128.4, 128.3, 127.8, 126.5, 125.8, 80.7, 78.4, 72.6, 29.9, 25.1. IR (neat) 3430, 2202, 1698, 1598, 1027, 699 cm -1 ; HRMS (CI+) m/z: (M-H) + Calcd for C 17 H 15 : 219.1174, found: 219.1174. H CH 3 syn-1-cyclohexyl-2-methyl-but-3-yn-1-ol (2l) colorless crystal, 51 mg (76%); 1 H-NMR (300 MHz, CDCl 3 ) δ ppm 3.35 (m, 1H), 2.72-2.58 (m, 1H), 2.10 (d, 1H, J = 2.4 Hz), 1.93 (bd, 1H, J = 13.1 Hz), 1.83-1.48 (m, 6H), 1.36-0.93 (m, 8H); 13 C-NMR (300 MHz, CDCl 3 ) δ 87.0, 78.1, 69.9, 39.8, 29.6, 29.4, 27.6, 26.4, 26.2, 25.9, 14.9. IR (neat) 3428, 3307, 2926, 2110, 1449, 976, 634 cm -1 ; MS (CI+) m/z: (M H) + Calcd for C 11 H 17 : 149.1, found: 149.1. (Previous report and S11

characterization data: Danheiser, R.L.; Carrie, D.J.; Kwasigroch, C.A. J. rg. Chem. 1986, 51, 3870-3878. H CH 3 anti-1-cyclohexyl-2-methyl-but-3-yn-1-ol (2m) colorless crystal, 49 mg (78%); 1 H-NMR (300 MHz, CDCl 3 ) δ ppm 3.07 (m, 1H), 2.77-2.66 (m, 1H), 2.10 (d, 1H, J = 2.4 Hz,), 2.02-1.89 (m, 1H), 1.82-1.59 (m, 5H), 1.55-1.39 (m, 1H), 1.30-0.94 (m, 8H); 13 C-NMR (300 MHz, CDCl 3 ) δ 85.1, 78.6, 70.8, 41.7, 29.7, 29.5, 28.3, 26.3, 26.2, 25.9, 18.1. IR (neat) 3432, 3307, 2925, 2110, 1449, 976, 633 cm -1 ; MS (CI+) m/z: (M H) + Calcd for C 11 H 17 : 149.1, found: 149.2. (Previous report and characterization data: Danheiser, R.L.; Carrie, D.J.; Kwasigroch, C.A. J. rg. Chem. 1986, 51, 3870-3878.) H 2-Benzyl-1-phenyl-but-3-yn-1-ol (2n) colorless oil, 53 mg (83%, anti/syn 19:1); 1 H-NMR (300 MHz, CDCl 3 ) δ ppm 7.49-7.11 (m, 10H), 4.64 (t, 1H, J = 5.3 Hz), 3.08-2.90 (m, 1H), 2.92-2.69 (m, 2H), 2.48 (d, 1H, J = 5.3 Hz), 2.18 (d, 1H, J = 2.3 Hz); 13 C-NMR (300 MHz, CDCl 3 ) δ 141.6, 138.8, 129.1, 128.4, 128.3, 127.9, 126.5, 126.4, 83.2, 74.6, 73.4, 42.9, 37.8. IR (neat) 3340, 2382, 1495, 1453, 1028, 699 cm -1 ; HRMS (EI+) m/z: (M) + Calcd for C 17 H 16 : 236.1201, found: 236.1205. S12

Tf 1a S13

Tf 1a S14

Tf Br 1b S15

Tf Br 1b S16

Tf H 3 C 1c S17

Tf H 3 C 1c S18

Tf 1d S19

Tf 1d S20

Tf 1e S21

Tf 1e S22

Tf 1f S23

Tf 1f S24

Tf 1g S25

Tf 1g S26

1h Tf S27

Tf 1h S28

Tf 1i S29

Tf 1i S30

CH 3 Tf 1j S31

CH 3 Tf 1j S32

Bn Tf 1k S33

Bn Tf 1k S34

Tf CH 3 1l S35

Tf CH 3 1l S36

Tf CH 3 1m S37

Tf CH 3 1m S38

Tf 1n S39

Tf 1n S40

H 2a S41

H 2a S42

H Br 2b S43

H Br 2b S44

H H 3 C 2c S45

H H 3 C 2c S46

H 2d S47

H 2d S48

H 2e S49

H 2e S50

H 2f S51

H 2f S52

H 2g S53

H 2g S54

H 2h S55

H 2h S56

H 2i S57

H 2i S58

H CH 3 2j S59

H CH 3 2j S60

H Bn 2k S61

H Bn 2k S62

H CH 3 2l S63

H CH 3 2l S64

H 2m CH 3 S65

H CH 3 2m S66

H 2n S67

H 2n S68