تفاعل #2659

معادلة التفاعل

trityl chloride

1,8-diazabicyclo[5.4.0]undec-7-ene

4-hydroxy-2-cyclopentenone

→

title compound

المردود 37.0%

4-trityloxy-2-cyclopentenone

المردود 37.0%

المذيبات

methylene chloride

ظروف التفاعل

المعالجة

1. 1
   workup.ADDITIONpoured onto ice (approximately 25 mL)
2. 2
   أخرىThe phases are separated
3. 3
   غسيلthe organic phase is washed with water (25 mL)
4. 4
   تجفيفThe organic phase is dried over anhydrous magnesium sulfate
5. 5
   ترشيحfiltered
6. 6
   تركيزconcentrated under vacuum
7. 7
   أخرىThe residue is purified by column chromatography (silica gel, 10-20% ethyl acetate/hexane)

الإجراء التجريبي

A solution of trityl chloride (3.44 g, 12.3 mmol) in methylene chloride (20 mL) is treated sequentially with 1,8-diazabicyclo[5.4.0]undec-7-ene (2.2 mL, 14.7 mmol, DBU) and 4-hydroxy-2-cyclopentenone (1.01 g, 10.0 mmol, in 5 mL of methylene chloride, prepared in example 1). The reaction is stirred for 3 days at room temperature and then poured onto ice (approximately 25 mL). The phases are separated and the organic phase is washed with water (25 mL). The organic phase is dried over anhydrous magnesium sulfate, filtered and concentrated under vacuum. The residue is purified by column chromatography (silica gel, 10-20% ethyl acetate/hexane) to provide the title compound (1.26 g, 36%) as a pale yellow oil; 1H NMR (CDCl3) δ7.5 (m, 6H), 7.3 (m, 9H), 6.85 (dd, 1H), 6.05 (d, 1H), 4.8 (m, 1H), 2.1 (m, 2H); 13C NMR (CDCl3) δ206.6, 162.9, 144.3, 135.2, 128.8, 128.4, 127.7, 88.2, 73.1, 43.4; IR (KBr) νmax 3061, 1719, 1491, 1449, 1352, 1181, 1107, 1053 cm-1.

المصدر