反应详情

To the above solution of 3,3-dibutyl-2,4-dioxa-3-stannaspiro[5.5]undec-8-ene 2 was added 5,5-diethyl-1,3-dioxane-2-thione 1 (10.39 g, 59.6 mmol) in several small portions at room temperature over a period of 20 min. The resulting mixture was allowed to stir at room temperature for 24 hours. The reaction was monitored by TLC (silica gel, 25% ether/hexanes). The reaction mixture was then concentrated under reduced pressure and the residue taken up with ethyl ether (white suspension formed upon standing). The ether solution was filtered and concentrated under reduced pressure to give light yellowish oil. The crude material was purified by column chromatography (silica gel, 10-15% ethyl ether/hexanes). The desired 3,3-diethyl-1,5,7,16-tetraoxadispiro[5.2.5.2]hexadec-11-ene (DECH 3) was obtained as colorless oil in 94% yield. 1H-NMR (CDCl3, 300 MHz) δ5.68-5.58 (m, 2H), 3.74-3.68 (4s, 8H), 2.08-1.94 (m, 4H), 1.63-1.56 t, 2H, J=6.6 Hz), 1.46-1.37 (q, 4H, J=7.5 Hz), 0.84-0.76 (t, 6H, J=7.5 Hz); —C-NMR (CDCl3, 75 MHz) δ126.03, 124.16, 114.68, 70.03, 69.32, 34.27, 30.50, 26.44, 23.14, 21.30, 13.92, 7.01; IR (neat) (cm−1) 3020, 2960, 2880, 1640, 1450, 1360, 1250, 1220, 1200, 1185, 1160, 1105, 1020, 995, 920, 730, 655; Anal. Calcd for C16H26O4: C, 68.06%; H, 9.28%; Found: C, 68.20%; H, 9.59%.

1. concentrationThe reaction mixture was then concentrated under reduced pressure
2. filtrationThe ether solution was filtered
3. concentrationconcentrated under reduced pressure
4. customto give light yellowish oil
5. customThe crude material was purified by column chromatography (silica gel, 10-15% ethyl ether/hexanes)