A solution of lithium diisopropylamide (1.8 M in tetrahydrofuran/heptane/ethylbenzene, 0.25 ml, 0.45 mmol) was added drop wise to a solution of 2-[3-(4-chloro-phenyl)-5-methyl-pyrazol-1-yl]-3-methoxy-cyclopent-2-enone (124 mg, 0.41 mmol) in anhydrous tetrahydrofuran (1 ml) at −78° C., under nitrogen, and allowed to stir at this temperature for 30 minutes. Tetrahydropyranyl-4-carbaldehyde (51.5 mg, 0.45 mmol) was added drop wise and the reaction stirred at −78° C. for a further 30 minutes. The reaction was allowed to warm to room temperature over 30 mins and quenched by the addition of 1 M hydrochloric acid (5 ml) and extracted with dichlormethane (3×10 ml) to give 223.5 mg of crude material. The crude material was dissolved in acetone (2 ml) and 2 M hydrochloric acid (2 ml) added. This solution was heated in the microwave (using “normal” absorbtion) for 1 h at 120° C. This solution was extracted with dichloromethane (2×10 ml) and the organics dried over magnesium sulfate and reduced in vacuo. The crude material was purified by reverse phase preparative HPLC (eluting with acetonitrile/water) to give 2-[3-(4-chloro-phenyl)-5-methyl-pyrazol-1-yl]-4-(tetrahydro-pyran-4-ylmethyl)-cyclopentane-1,3-dione (32.2 mg).
