The condensation of diethyl 2-acetylglutarate (I) with 5-(1,1-dimethylheptyl)resorcinol (II) by means of POCl3 gives ethyl 7-(1,1-dimethylheptyl)-5-hydroxy-4-methyl-2-oxo-2H-1-benzopyran-3-propionate (III), which is cyclized by means of NaH in DMSO yielding 3-(1,1-dimethylheptyl)-7,10-dihydro-1-hydroxy-6H-dibenzo[b,d]pyran-6,9-(8H)-dione (IV). The ketalization of (IV) with ethylene glycol (A) and p-toluenesulfonic acid affords the ketal (V), which by a Grignard reaction with methylmagnesium iodide in refluxing ether is converted into dl-3-(1,1-dimethylheptyl)-6,6a,7,8-tetrahydro-1-hydroxy-6,6-dimethyl-9H-dibenzo[b,d]pyran-9-one (VI). Finally, this compound is reduced with Li in liquid ammonia.