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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.

1. customAcrylic acid 4,4-dimethyl-2-oxo-tetrahydro-furan-3-yl ester (R) was prepared in the following manner
2. washthe organic layer was washed with sodium bicarbonate and water
3. dry with materialThe organic layer was dried over sodium sulfate
4. filtrationfiltered
5. concentrationconcentrated