Reaktion #984009

Reaktionsgleichung

compound ( 2f )

(5S)-5-(Tetrahydropyran-2-yloxymethyl)-5H-furan-2-one

benzophenone

ethyl acetate

CHCl3

→

compound ( 3f )

(4S,5S)-4-([1,3]Dioxolan-2-yl)-5-(tetrahydropyran-2-yloxymethyl)-dihydrofuran-2-one

Lösungsmittel

[1,3]-dioxolane

—

hexanes

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigewas irradiated at 20° C. for 5.75 hours

Vorschrift

A solution containing 136 mg (0.686 mmol) compound (2f) and 18.7 mg (0.103 mmol) benzophenone in 100 mL [1,3]-dioxolane was irradiated at 20° C. for 5.75 hours according to the general procedure. Column chromatography (silica gel 40 g, ethyl acetate in hexanes 60%) gave compound (3f) as two diastereomers (170 mg, 91%) as a colorless oil, Rf=0.25, [α]25D −129°, c 0.8, CHCl3. 1H-NMR (300 MHz, CDCl3) δ: 1.38-1.82 (m, 6H), 2.40-2.46 (m, 1H), 2.60-2.75 (m, 2H), 3.39-3.48 (m, 1H), 3.61-3.70 (m, 1H), 3.75-3.81 (m, 2H), 3.84-3.87 (m, 2H), 3.93-3.98 (m, 2H), 4.53-4.63 (m, 2H), 4.86-4.89 (m, 1H). 13C-NMR (75.4 MHz, CDCl3, Dept) diastereomer A: δ: 18.72 (−), 25.20 (−), 29.98 (−), 30.02 (−), 40.08 (+), 61.52 (−), 64.68 (−), 65.33 (−), 68.33 (−), 78.98 (+), 98.21 (+), 103.64 (+), 176.51 (quat); B: δ: 19.23 (−), 25.20 (−), 30.21 (−), 30.24 (−), 40.08 (+), 62.20 (−), 65.05 (−), 65.45 (−), 68.81 (−), 79.08 (+), 99.09 (+), 103.71 (+), 176.72 (quat). C13H20O6; Exact Mass: 272.13; Mol. Wt.: 272.29; C, 57.34; H, 7.40; O, 35.25.

Quelle