The 2-chloro-4,4,6,6-tetramethylcyclohexene aldehyde (II), prepared by a Vilsmeier reaction on commercially available 3,3,5,5-tetramethylcyclohexanone (I), underwent a copper catalyzed 1,4 addition of the Grignard reagent derived from 5-bromo-2-fluorotoluene(III) to yield the 2-aryl substituted 4,4,6,6-tetramethylcyclohexene aldehyde (IV). Treatment of the aldehyde (IV) with the anion of ethylidenecyclohexylamine (V), followed by hydrolysis of the intermediate beta-hydroxyimine by silica gel chromatography, gave the extended aldehyde (VI). Addition of the dianion of methyl acetoacetate (VII) to aldehyde (VI) and stereospecific reduction of the resulting delta-hydroxy-beta-ketoester (VIII) with triethylborane and sodium borohydride yielded the erythro 3,5-dihydroxy methyl ester (IX). Hydrolysis of the methyl ester, followed by lactonization with triethylamine and methyl chloroformate produced dalvastatin).

The 2-chloro-4,4,6,6-tetramethylcyclohexene aldehyde (II), prepared by a Vilsmeier reaction on commercially available 3,3,5,5-tetramethylcyclohexanone (I), underwent a copper catalyzed 1,4 addition of the Grignard reagent derived from 5-bromo-2-fluorotoluene(III) to yield the 2-aryl substituted 4,4,6,6-tetramethylcyclohexene aldehyde (IV). Treatment of the aldehyde (IV) with the anion of ethylidenecyclohexylamine (V), followed by hydrolysis of the intermediate beta-hydroxyimine by silica gel chromatography, gave the extended aldehyde (VI). Addition of the dianion of methyl acetoacetate (VII) to aldehyde (VI) and stereospecific reduction of the resulting delta-hydroxy-beta-ketoester (VIII) with triethylborane and sodium borohydride yielded the erythro 3,5-dihydroxy methyl ester (IX). Hydrolysis of the methyl ester, followed by lactonization with triethylamine and methyl chloroformate produced dalvastatin).