2-Methyl-6-methylene-2,7-octadien

Scolytidae. The worldwide ranges of bark beetles have made them ideal candidates for research directed toward the isolation and identification of pheromones that can be used for population monitoring and regulation. A decade ago, the aggregative pheromone liberated by males of Ips paraconfusus (=confusus) was identified as a mixture of (-)-2-methyl-6-methylene-7-octen-4-ol (ipsenol) (XVI), (+)-cis-verbenol (XVII), and (+)-2-methyl-6-methylene-2,7-octadien-4-ol (ipsdienol) (XVIII)... 

The major aggregation pheromone components of T. typographies are e-is-verbenol and 2-methyl-3-buten-ol (1). Cis-verbenol is common to several Ips species (2). Only the Ts)-(-) enantiomer evokes response in field experiments (3). Methylbutenol is specific to I. typographies. A different isomer is part of the pheromone of the related species Ips oembrae, which lives on larch in Europe C4). Ipsdienol (2-methyl-6-methylene-2, 7-octadiene-4-ol), which... 

Shiso Perilla frutescens var. crispa (S)-Perillaldehyde (142), 2-methyl-6-methylene-2,7-octadienal (143), trans-shisool (144) 165... 

Lippia dauensis (Chiov.) Chiov. L. dauensis oil was obtained from plants collected in the north-eastern arid region of the country. The semi-dried leaves and flowering tops of the plant produced 2.4% oil contaiiung p-ocimene (24.7%), 2-methyl-6-methylene-7-octen-4-one (15.7%), myrcene (12.9%), cis-tagetone (11.0%), and 2-methyl-6-methylene-2,7-octadien-4-ol (9.4%). The... 

A.45) 1,6-Octadiene, 7-methyl-3-methylene-, 7-methyl-3-methyleneoeta-l,6-diene, 2-methyl-6-methylene-2,7-octadiene, (3-myrcene [123-35-3] FEMA 2762... 

METHYL-6-METHYLENE-2,7-OCTADIENE (123-35-3) Forms explosive mixture with air (flash point 103°F/40°C). Violent reaction with strong oxidizers, bromine, perchlorates, perchromates, pyridinium perchlorate, peroxyacetic acid, peroxybenzoic acid. Attacks some plastics, rubber, and coatings. Flow or agitation of substance may generate electrostatic charges due to low conductivity. 

Methyl-6-methylene-2,7-octadiene 7-Methyl-3-methylene-1,6-octadiene 7-Methyl-3-methylene-octa-1,6-diene. See Myrcene... 

The direct reaction of 2-trimethylsilylmethyl-1,3-butadiene with isovaleraldehyde gives ( )-ipsenol (2-methyl-6-methylene-7-octen-4-ol) in rather low yield (30%) (eq 5). However, ipsenol is obtained in 62% overall yield by the reaction of 2-trimethylsilylmethyl-1,3-butadiene with isovaleryl chloride, followed by reduction with diisobutylaluminum hydride (eq 7). Similarly, ( )-ipsdienol (2-methyl-6-methylene-2,7-octadien-4-ol) is obtained by reduction of myrcenone, prepared by the reaction of 2-trimethylsilylmethyl-1,3-butadiene with 3,3-dimethylacryloyl chloride, in 75% overall yield (eq 8). 

Further experiments of this type by Renwick et al. (396) established that D. brevicomis and D. frontalis oxidize camphene (619) to 6-hydroxy-camphene (camphenol, 620). Both sexes of D. brevicomis transformed myrcene into 2-methyl-6-methylene-2,7-octadien-l-ol (myrcenol, 621), whereas ipsdienol was a major product in males only. 

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