TERPENES IN ORGANIC SYNTHESIS. 13. SYNTHESIS OF S-(+)-METHOPRENE FROM (+)-&β-CITRONELLENE

Article abstract of DOI:10.1007/BF00958564

S-(+)-Methoprene (I) was synthesized from (+)-β-citronellene (III) with an optical purity of about 50percent.The optical purity of the key intermediate, S-(-)-7-methoxy-3,7-dimethyl-1-octanol (IV), can be increased by fractional crystallization of the optical active acid phthalate salt (VI) followed by hydrolytic crystallization of the alcohol (IV).The yield of (I) at the final synthetic stage can be increased by use of interphase catalysis.S-(+)-Methoprene has a higher morphogenetic activity than the racemic form.