16-methyloctadecanoic acid

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a four-necked 50 mL of flask equipped with a refluxing condenser tube, a 10 mL of dropping funnel, a magnetic stirrer and a temperature sensor, 15-bromopentadecanoic acid of 1.01 g (3.14 mmol) and 18-crown-6 of 823.3 mg (1.0 eq) were added and dried under reduced pressure. Under argon atmosphere, copper bromide (I) of 13.3 mg (0.03 eq) and anhydrous tetrahydrofuran of 6 mL were added to dissolve the materials. At room temperature, sec-butyl magnesium bromide of 7.85 mL (2.5 eq, 1.0M tetrahydrofuran solution) was added dropwise thereto over thirty minutes. After stirring for one hour, 5 mL of 6N aqueous sulfuric acid solution was added and the extraction was carried out by using 10 mL of hexane. After washing twice with 10 mL ion exchange water, the mixture was dried over magnesium sulfate. After the filtration, the crude product (0.84 g) was obtained by concentration under reduced pressure. To a four-necked 50 mL of flask equipped with a refluxing condenser tube dried under reduced pressure Under argon atmosphere, copper bromide (I) of 13.3 mg (0.03 eq) and anhydrous tetrahydrofuran of 6 mL were added to dissolve the materials over thirty minutes the extraction After washing twice with 10 mL ion exchange water the mixture was dried over magnesium sulfate After the filtration

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 16-Methyloctadecanoic acid was synthesized by the same operation, except that in the step (a) of the synthesis process for 14-methylhexadecanoic acid described above, 12-dodecanolide was changed to 15-pentadodecanolide, and in the step (b), 2-methylbutylmagnesium bromide was changed to sec-butylmagnesium bromide. Thus, 16-methyloctadecanoic add was obtained from 15-pentadodecanolide at a total yield of 84%. The purity was 95%. Thus, 16-methyloctadecanoic add