We describe a novel and straightforward route to all stereoisomers of 1,10-bisaboladien-3-ol and 10,11-epoxy-1-bisabolen-3-ol via the rhodium-catalyzed asymmetric addition of trimethylaluminum to diastereomeric mixtures of cyclohex-2-enones 1 and 2. The detailed stereoisomeric structures of many natural sesquiterpenes with the bisabolane skeleton were previously unknown because of the absence of stereoselective syntheses of individual stereoisomers. Several of the bisabolenols are pheromones of economically important pentatomid bug species. Single-crystal X-ray crystallography of underivatized triol 13 provided unequivocal proof of the relative and absolute configurations. Two of the epoxides, (3S,6S,7R,10S)-10,11-epoxy-1-bisabolen-3-ol (3) and (3R,6S,7R,10S)-10,11-epoxy-1-bisabolen-3-ol (4), were identified as the main components of a male-produced aggregation pheromone of the brown marmorated stink bug, Halyomorpha halys, using GC analyses on enantioselective columns. Both compounds attracted female, male, and nymphal H. halys in field trials. Moreover, mixtures of stereoisomers containing epoxides 3 and 4 were also attractive to H. halys, signifying that the presence of additional stereoisomers did not hinder attraction of H. halys and relatively inexpensive mixtures can be used in monitoring, as well as control strategies. H. halys is a polyphagous invasive species in the U.S. and Europe that causes severe injury to fruit, vegetables, and field crops and is also a serious nuisance pest. T he bisabolane skeleton is a recurring structural motif in the semiochemistry of stink bugs (Hemiptera: Pentatomidae). Bisabolene epoxides comprise male-specific pheromones of Nezara viridula 1,2 and Chinavia (=Acrosternum) spp. 3,4 The related zingiberene, β-sesquiphellandrene, and α-curcumene constitute part of the Thyanta pallidovirens pheromone, 5 and β-sesquiphellandrene was identified as a pheromone component of Piezodorus hybneri. 6 More recently, two stereoisomeric 1,10-bisaboladien-3-ols 7 were identified as part of the male-produced pheromone of the rice stalk stink bug, Tibraca limbativentris, 8 and 10,11-epoxy-1-bisabolen-3-ol (called "murgantiol") has been reported as an aggregation pheromone of the harlequin bug, Murgantia histrionica. 9,10 As with murgantiol, the relative and absolute configurations of the 1,10-bisaboladien-3-ols from T. limbativentris have not been determined. Reliable assignment of relative configurations across the cyclohexene ring of the murgantiol structure was problematic, and 1 H and 13 C NMR recordings of murgantiol failed to provide a conclusive answer. 9 Several related compounds were isolated from the oil of ginger, Zingiber off icinale, among them a 1,10-bisaboladien-3-ol, called "zingiberenol". 11 The latter was assigned a trans-configuration based on similarities of its IR spectrum with that of trans-p-menth-2-en-1-ol, 12 but the structure was presented as the cis-isomer 11 and the absolute configuration has not been disclosed. A sex pheromone of the rice stink bug, Oebalus poecilus, has recently been also identified as zingiberenol and, more specifically, (1R,4R,1′S)-(1′,5′-dimethylhex-4′-enyl)-1-methyl-cyclohex-2-en-1-ol. 13 The absolute configuration has been assigned based on the correlation to natural zingiberene and similarities of 13 C NMR spectra of a synthetic mixture containing the pheromone and (R,R)-quercivorol. However, the pher-omone of O. poecilus has not been synthesized in pure form and