[O:1]([C:8]1[CH:13]=[CH:12][C:11]([OH:14])=[CH:10][CH:9]=1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[OH-].[K+].C1OCCOCCOCCOCCOCCOC1.[CH2:35]([O:37][CH:38]([O:45][CH2:46][CH3:47])[C:39]#[C:40][C:41]([O:43][CH3:44])=[O:42])[CH3:36]>C1COCC1.O>[CH2:46]([O:45][CH:38]([O:37][CH2:35][CH3:36])/[C:39](/[O:14][C:11]1[CH:10]=[CH:9][C:8]([O:1][C:2]2[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=2)=[CH:13][CH:12]=1)=[CH:40]/[C:41]([O:43][CH3:44])=[O:42])[CH3:47]To a solution of 2.79 g (15 mmol) of 4-phenoxyphenol in 40 mL of THF was added 1.14 g (20 mmol) of powdered KOH and 5.28 g (20 mmol) of 18-crown-6. The solution was heated to 50° C. for 15 minutes, whereupon 3.72 g (20 mmol) of methyl 4,4-diethoxy-2-butynoate was added. The mixture was stirred for 30 minutes, then allowed to cool to room temperature. The solution was then poured into water, and extracted 3 times with 40 mL of ethyl acetate. The organic layers were combined, dried (MgSO4) and concentrated. The crude oil was subjected to column chromatography on SiO2. Elution with 20% ethyl acetate-hexane yielded 3.02 g (55%) of an oil, used in the next step without further purification.
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