methyl 4-chloro-2-methylbutanoate

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

Procedure: (2S,4R)-N-(4-Chloro-phenyl)-N-[1-(4-hydroxy-benzoyl)-2-methyl-1,2,3,4-tetrahydro-quinolin-4-yl]-acetamide (230 mg, 0.531 mmol) was dissolved in DMF (5 mL) at room temperature. Cs2CO3 (433 mg, 1.33 mmol) was added followed by 4-chloro-2-methyl-butyric acid methyl ester (120 mg, 0.796 mmol) and the reaction was allowed to stir overnight. The mixture was partitioned between methylene chloride and water; the organic layer was dried over Na2SO4, filtered and concentrated. The crude residue was purified by silica gel chromatography (1/1 hexanes/ethyl acetate—ethyl acetate gradient) to afford the product. The mixture was partitioned between methylene chloride and water the organic layer was dried over Na2SO4 filtered concentrated The crude residue was purified by silica gel chromatography (1/1 hexanes/ethyl acetate—ethyl acetate gradient) to afford the product

Conditions: temp:150.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: contacting the xylene solution of methyl 4-chloro-2-methylbutyrate from step (3) with an sodium methoxide and heating at temperatures of about 100 to 200° C. which causes vaporization of (i) methanol as it is formed and (ii) methyl 1-methylcyclopropanecarboxylate as it is formed from methyl 4-chloro-2-methylbutyrate. is formed