(2S)-2-[[tert-butyl(dimethyl)silyl]oxymethyl]-2H-furan-5-one

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution containing 228 mg (0.998 mmol) compound (2a) and 18.0 mg (0.998 mmol) benzophenone in 200 mL [1,3]-dioxolane was irradiated at 20° C. for 5 hours according to the general procedure. Column chromatography (silica gel 35 g, ethyl acetate in hexanes 30%) gave compound (3a) (285 mg, 94%) as a colorless solid, Rf=0.35, [α]25D 18.3°, c 1.3, CHCl3, IR (neat) 2953, 2857, 1778, 1125 cm−1; 1H-NMR (300 MHz, CDCl3) δ: 0.05 (s, 6H), 0.87 (s, 9H), 2.45 (dd, 1H, J=4.2 Hz, J=17.7 Hz), 2.68 (d, 1H, J=17.7 Hz), 2.72-2.79 (m, 1H), 3.65 (dd, 1H, J=2.7 Hz, J=11.4 Hz), 3.86-3.91 (m, 3H), 3.97-4.01 (m, 2H), 4.50 (mc, 1H), 4.88 (d, 1H, J=3.6 Hz). 13C-NMR (75.4 MHz, CDCl3, Dept) δ: 5.52 (+), 18.18 (quat), 25.77 (+), 30.12 (−), 39.67 (+), 64.71 (−), 65.36 (−), 65.47 (−), 80.24 (+), 103.94 (+), 176.55 (quat). C14H26O5Si; Exact Mass: 302.15; Mol. Wt.: 302.44; C, 55.60, H, 8.67, O, 26.45, Si, 9.29. was irradiated at 20° C. for 5 hours

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution containing 228 mg (0.998 mmol) compound (2a) and 18.0 mg (0.998 mmol) benzophenone in 200 mL [1,3]-dioxolane was irradiated at 20° C. for 5 hours according to the general procedure. Column chromatography (silica gel 35 g, ethyl acetate in hexanes 30%) gave compound (3a) (285 mg, 94%) as a colorless solid, Rf=0.35, [α]25D 18.3°, c 1.3, CHCl3, IR (neat) 2953, 2857, 1778, 1125 cm−1; 1H-NMR (300 MHz, CDCl3) δ: 0.05 (s, 6H), 0.87 (s, 9H), 2.45 (dd, 1H, J=4.2 Hz, J=17.7 Hz), 2.68 (d, 1H, J=17.7 Hz), 2.72-2.79 (m, 1H), 3.65 (dd, 1H, J=2.7 Hz, J=11.4 Hz), 3.86-3.91 (m, 3H), 3.97-4.01 (m, 2H), 4.50 (mc, 1H), 4.88 (d, 1H, J=3.6 Hz). 13C-NMR (75.4 MHz, CDCl3, Dept) δ: 5.52 (+), 18.18 (quat), 25.77 (+), 30.12 (−), 39.67 (+), 64.71 (−), 65.36 (−), 65.47 (−), 80.24 (+), 103.94 (+), 176.55 (quat). C14H26O5Si; Exact Mass: 302.15; Mol. Wt.: 302.44; C, 55.60, H, 8.67, O, 26.45, Si, 9.29. was irradiated at 20° C. for 5 hours