Synthesis of Longhorn Beetle Pheromone Components by Proline-Mediated α-Hydroxylation of Alkyl Ketones

Abstract

The stereoselective synthesis of several components of the aggregation pheromones of numerous longhorn beetle species is described. These attractants consist in 3-hydroxy-2-alkylketones and 2,3-alkyldiols with chain lengths varying from six to ten carbons. The 3R- and 3S-series are generated by organocatalytic α-hydroxylation of alkylketones with nitrosobenzene in the presence of L- or D-proline, respectively, to obtain the hydroxyketones in high enantiomeric excess. Further reduction and chromatographic separation leads to the enantiomerically pure diols that complete the library

Recent advances in the synthesis of insect pheromones: an overview from 2013 to 2022

“…Fig. 4 includes the pheromones of Formica polyctena (Hym., Formicidae) 23 , 42 longhorn beetles (Col., Cerambycidae): 24–26 , 43 Haplodiplosis marginata (Dip., Cecidomyiidae): ( R )- 27 , ( R )- 28 , and ( R )- 29 , 44 Bactrocera oleae (Dip., Tephritidae): 30–39 , 45 Cnaphalocrocis medinalis (Lep., Pyralidae): 40 and 41 , 46 moth (Lep. ): 42 , 47 Plutella xylostella (Lep., Plutellidae): 43 , 48 Trichoplusia ni (Lep., Noctuidae): 44 , 49 Tortrix viridana (Lep., Tortricidae): 45 , 50 Grapholita molesta , G. funebrana , and Hedya nubiferana (Lep., Tortricidae): ( E )- and ( Z )- 46 , 51 Plutella xylostella (Lep., Plutellidae): 47 , 52 moth (Lep.)…”