Stereoselective Allylation of Chiral Monoperoxyacetals.

Abstract

For Abstract see ChemInform Abstract in Full Text.

Enantioselective synthesis and sensory properties of 3‐methylthiodecanal

“…1 H NMR (300 MHz, CDCl 3 ) δ 0.88 (t, J = 7.2 Hz, 3 H, H‐C11), 1.20–1.62 (m, 12 H, H‐C5‐C10), 2.33 (m, 2H, H‐C3), 3.44 (m, 1 H, H‐C4), 4.49 (d, J = 11.7 Hz, 1 H, CH 2 (benzyl)), 4.57 (d, J = 11.7 Hz, 1 H, CH 2 (benzyl)), 5.02–5.15 (m, 2 H, H‐C1), 5.86 (m, 1 H, H‐C2), 7.26–7.42 (m, 5 H, phenyl); 13 C NMR (75 MHz, CDCl 3 ) δ 14.1 (C11), 22.7 (C10), 25.4 (C6), 29.3 (C8), 29.7 (C7), 31.9 (C9), 33.8 (C5), 38.3 (C3), 70.9 (CH 2 (benzyl)), 78.6 (C4), 116.8 (C1), 127.4 (C4 (phenyl)), 127.7 (C3 and C5 (phenyl)), 128.3 (C2 and C6 (phenyl)), 135.2 (C2), 139.0 (C1 (phenyl)). The NMR data were consistent with the literature data …”

Cobalt-Catalyzed Intramolecular Silylperoxidation of Unsaturated Diisopropylsilyl Ethers

“…All 1 H and 13 C NMR spectra were recorded at ambient temperature at 400, 500, and 600 MHz or 100, 125, and 150 MHz, respectively. The data were reported as follows: chemical shifts reported in parts per million from residual solvent peaks ( 1 H NMR CDCl 3 δ 7.26, C 6 D 6 δ 7.16; 13 C NMR CDCl 3 δ 77.23, C 6 D 6 δ 128.4) on the δ scale, multiplicity (s, singlet; br, broad; d, doublet; t, triplet; q, quartet; quint, quintet; dd, doublet of doublets; m, multiplet), coupling constant (hertz), and integration. The multiplicities of carbon peaks were determined using HSQC or DEPT experiments.…”

“…The combined organic layers were dried over MgSO 4 and concentrated in vacuo. Purification by flash chromatography (hexanes/EtOAc = 90:10) afforded 2-(4-methoxyphenyl)-3,3-dimethylpent-4-en-2-ol (0.324 g, 74%) as a colorless oil: 1 H NMR (400 MHz, CDCl 3 ) δ 7.33 (d, J = 8.8, 2H), 6.84 (d, J = 8.8, 2H), 5.96 (dd, J = 17.6, 10.9, 1H), 5.13−5.00 (m, 2H), 3.81 (s, 3H), 1.88 (s, 1H), 1.56 (s, 3H), 1.00 (s, 3H), 0.98 (s, 3H); 13 2-(4-Methoxyphenyl)-4-methylpent-4-en-2-ol. To a solution of ketone 11 (0.300 g, 2.00 mmol) in THF (6.0 mL) at 0 °C was added a solution of 2-methylallylmagnesium chloride in THF (0.5 M, 4.4 mL, 2.2 mmol) dropwise.…”

“…The reaction time was 35 min. Purification by flash chromatography (hexanes/EtOAc = 95:5) afforded diisopropylsilyl ether 12 (0.525 g, 64%) as a colorless oil: 1 ((2-Cyclohexylpent-4-en-2-yl)oxy)diisopropylsilane (13). Diisopropylsilyl ether 13 was prepared using the representative procedure for the silylation of alcohols using 2-cyclohexylpent-4-en-2-ol (0.389 g, 2.31 mmol), 1H-imidazole (0.314 g, 4.62 mmol), and diisopropylchlorosilane (0.434 mL, 2.54 mmol) in THF (7.0 mL).…”

“…3,12 In this Article, we report that unsaturated diisopropylsilyl ethers can undergo an intramolecular silylperoxidation reaction to form 3sila-1,2,4-trioxepanes (Scheme 1, eq 3). 13 Upon reduction of the peroxide unit using triphenylphosphine, the corresponding silylene-protected 1,3-diol was formed.…”