Scolytus multistriatus 4-Methyl-3-heptanol

Sn2 Reactions with epoxides and aziridines are also synthetically useful. An example of epoxide cleavage with an organocopper reagent with sp carbon moieties is the enantioselective synthesis of (3S, 4S)-4-methyl-3-heptanol (53), an elm bark beetle (Scolytus multistriatus) pheromone [42]. The chiral epoxy oxazolidine 51 [43], prepared from (R)-phenylglycinol, reacted with a propylmagnesium bromide-derived cuprate at —70 °C to afford the oxazolidine 52 in 74% yield (Scheme 9.12). Compound 52 was converted into the target molecular 53 by conventional procedures. 

The terpenoid-exocrine theme emphasized by scolytid beetles was again evident when the chemical constitution of the secondary attractant for the smaller European elm bark beetle, Scolytus multistriatus, was elucidated. The aggregation pheromone was identified as a mixture of (-)-4-methyl-3-heptanol, 2,4-dimethyl-5-ethyl-6,8-dioxabicyclo [3.2.1]octane (multistriatin) (XXII), and (-)-a-cubebene (XXIII), a host-derived synergist (70). All three compounds are required for the maximum attraction of beetles. The inactive diastereomers of 4-methyl-3-heptanol and multistriatin did not inhibit the responses of airborne beetles. 

Such a sequence has been successfully used115 for the synthesis of 4-methyl-3-heptanol, the major constituent of the aggregation pheromone of the elm bark beetle (Scolytus multistriatus Marsham)117 and zir-butyM-methyltetrahydro-2-furanone118 known as quercus lactone or oak lactone. ... 

Recordings of olfactory receptor cells in Scolytus multistriatus and S. scolytus revealed the same degree of specialization as that found for Ips species. In males of S. multistriatus (attracted to the three-component mixture, multilure) the majority of receptor cells were keyed to either of the two compounds produced by females, (- )-a-multistriatin and (- )-threo-4-methyl-3-heptanol (Angst, 1981). 

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