Hydrochloric Acid → Acrylic acid 4,4-dimethyl-2-oxo-tetrahydro-furan-3-yl ester

Beteiligte Stoffe

Reaktionsschritte

Acrylic acid 4,4-dimethyl-2-oxo-tetrahydro-furan-3-yl ester (R) was prepared in the following manner: 3-(S)-Hydroxy-4,4-dimethyl-dihydro-furan-2-one (2.60 g, 20 mmol) and diisopropylethylamine (5.2 mL, 30 mmol) in dichloromethane (25 mL) was cooled to −10° C. and treated dropwise with acryloyl chloride (2.03 mL, 25 mmol) and stirred for 2 h. 1M HCl (20 mL) was added and the organic layer was washed with sodium bicarbonate and water. The organic layer was dried over sodium sulfate, filtered and concentrated. Flash chromatography (10-40% EtOAc, hexanes) afforded 2.09 g (57% yield) of the desired acrylic acid 4,4-dimethyl-2-oxo-tetrahydro-furan-3-yl ester (R) as a clear oil. This substrate was used to prepare the acid chloride of (1R)-4-methyl-cyclohex-3-enecarboxylic acid analogous to the procedure described in Scheme 15 and Scheme 16.

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