methyl 4-cyclohexyl-3-oxobutanoate

Conditions: temp:25.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A 250 ml flask was charged with 15.0 g of methyl 4-cyclohexyl-3-oxobutanoate (96% GC, 1 molar equivalent) and 9.8 g of methallyl chloride (1.5 molar equivalent). The mixture was heated to 70° C. and over the course of 90 minutes 13 g of a 30% solution of sodium methylate in methanol (1 molar equivalent) was added. Stirring was continued for 30 minutes and then 50 g of toluene was added. Within 1 hour 19.3 g of a 30% aqueous sodium hydroxide solution was added and stirring continued for 1 hour. After cooling to 25° C., 28.4 g of a 50% aqueous sulfuric acid solution was added over the course of 1 hour. To the slurry 70 g toluene and 40 g water were added and after decantation, the aqueous phase was drained. After concentration the crude product was fractionated leading to 8.9 g of 1-cyclohexyl-5-methylhex-5-en-2-one (95% GC, 60% yield). was added stirring continued for 1 hour After concentration the crude product

Conditions: temp:25.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A 500 ml flask was charged with 120 g xylene, 33.8 g of solid potassium methylate (3.2 molar equivalent) and 34.0 g of dimethylcarbonate (2.5 molar equivalent). The slurry was heated to 50° C. and over the course of 4 hours 24.2 g of 1-cyclohexylpropan-2-one (87% GC, 1 molar equivalent) was added. Stirring was continued for 2 hours and then the reaction mixture was cooled to 25° C. 95 g of an acetic acid/water mixture (1:2) was then added carefully. After decantation the aqueous phase was drained and the organic phase concentrated. The crude product was distilled leading to 24.9 g of methyl 4-cyclohexyl-3-oxobutanoate (81% GC, 68% yield). was added the organic phase concentrated The crude product was distilled

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

Procedure: Under the same conditions as in Example 1, 116 g (1.0 mol) of methyl acetoacetate in a mixture of 520 ml of methylene chloride and 30 ml of methyl ethyl ketone were reacted with 77.8 g (1.05 mol) of calcium hydroxide and 176.7 g (1.1 mol) of cyclohexylacetyl chloride. The subsequent reaction time after the ammonia had been metered in was 6 hours at a pH of 9.5. This gave 196 g (GC purity 75.0%) of methyl 4-cyclohexylacetoacetate (yield 74.5%).