70639-20-2

Upstream product

• 29117-58-6 (2S,3S)-3-Methyl-pentane-1,2-diol 
• 98-59-9 p-toluenesulfonyl chloride 
• 488-15-3 (2S,3S)-2-Hydroxy-3-methylpentanoic acid 
• 94424-88-1 (2R,3R)-3-(ethyloxiran-2-yl)methanol 
• 6261-22-9 pent-2-yn-1-ol 
• 1576-96-1 (E)-2-penten-1-ol 

Downstream Products

• 35399-81-6 (1S,2R)-1,2-Dimethylbutylamin 
• 88196-67-2 (1R,2R)-1,2-Dimethylbutylamin 
• 73153-83-0 (1S,2S)-1,2-Dimethylbutylamin 
• 73153-92-1 (1R,2S)-1,2-Dimethylbutylamin 
• 73153-89-6 Toluene-4-sulfonic acid (2S,3S)-3-methyl-2-(tetrahydro-pyran-2-yloxy)-pentyl ester 

Relevant academic research and scientific papers

PHEROMONE CHIRALITY OF AFRICAN PALM WEEVIL, Rhynchophorus phoenicis (F.) AND PALMETTO WEEVIL, Rhynchophorus cruentatus (F.) (COLEOPTERA: CURCULIONIDAE)

There are four stereoisomers of both 3-methyl-octan-4-ol, the aggregation pheromone of the African palm weevil, Rhynchophorus phoenicis (F.) and 5-methyl-octan-4-ol, the aggregation pheromone of the palmetto weevil, Rhynchophorus cruentatus (F.). Synthetic stereoisomers of 3-methyl-octan-3-ol and 5-methyl-octan-4-ol were baseline-separated on a Cyclodex-B fused silica column. Use of this column in gas chromatographic-electroantennographic detection (GC-EAD) and GC-mass spectrometric (GC-MS) analyses revealed that only one stereoisomer, (3S,4S)-3-methyl-octan-4-ol and (4S,5S)-5-methyl-octan-4-ol, is produced by male R. phoenicis and male R. cruentatus, respectively, and elicits good antennal responses by conspecific male and female weevils. In field trapping experiments, with R. phoenicis in Cote d'Ivoire and R. cruentatus in Florida, (3S,4S)-3-methyl-octan-4-ol and (4S,5S)-5-methyl-octan-4-ol strongly enhanced attraction of fresh palm tissue, whereas other stereoisomers were behaviorally benign. Stereoisomeric 3-methyl-octan-4-ol and 5-methyl-octan-4-ol may be utilized to monitor and/or manage populations of these two palm weevils. - Keywords: Coleoptera, Curculionidae, Rhynchophorus phoenicis, Rhynchophorus cruentatus, aggregation pheromone, pheromone chirality, (3S,4S)-3-methyl-octan-4-ol, (3R,4R)-3-methyl-octan-4-ol, (3S,4R)-3-methyl-octan-4-ol, (3R,4S)-3-methyl-octan-4-ol, (4S,5S)-5-methyl-octan-4-ol, (4R,5R)-5-methyl-octan-4-ol, (4S,5R)-5-methyl-octan-4-ol, (4R,5S)-5-methyl-octan-4-ol

Stereochemistry of Aliphatic Carbocations, 12. Alkyl Shifts between Secondary Carbon Atoms

Several optically active, β-branched alkylamines have been synthesized from amino acids.The corresponding amines were obtained from isobutyraldehyde and 2-methylbutanal (37), respectively.The stereochemistry at the terminus of 1,2-methyl shifts has been elucidated in the nitrous acid deaminations of 4 and 21.Predominant, although incomplete inversion at the migration terminus is consistent with conformational control rather than neighboring group participation.The deamination of 31 involves a degenerate 1,2-ethyl shift and a nondegenerate 1,2-methyl shift, the reverse holds for 44.Complete inversion at the origin of the methyl migrations and the absence of subsequent retrogressive H shifts strongly support the intermediacy of methyl-bridged carbocations.Partial racemization at the origin of the ethyl migrations has been traced to proton shifts within ethyl-bridged intermediates.Rearranged open cations contribute significantly to the overall reaction if micelles are produced by self-aggregation of the alkylammonium ions.