209 



zea (Boddie); and the cabbage looper, Trichoplusia ni (HUbner); in a Georgia 

 cotton field. The data obtained reflect the physical, mathematical, biological 

 and meteorological factors which determine transport to and impingement 

 of the insecticide sprays on these insects in their widely diverse environments. 

 A total of 101,495 spray droplets was identified by size and counted on 1324 

 insects. Eight droplets were identified in the 101-120 \i range; droplets 

 less than 50 y diameter constituted 99.7% of the total. The data show that 

 the maximum diameter for efficient insecticide spray droplets is less than 

 50 p. There is no evidence that spray droplets larger than 100 y have any 

 substantial efficiency in delivery of insecticide. to these insects. 



405. Hobbs, P. D. , and Magnus, P. D. 1974. Synthesis of optically active 



grandisol. Chem. Commun. 21: 856-857. 

 This particular synthesis offers the possibility of preparing analogues via 

 Wittig reactions on the lactol (III). The unusual photochemical transforma- 

 tion (XI) -> (XII), generating the isopropenyl group and exposing the cyclo- 

 butane ring with the quaternary centre in the correct absolute configuration 

 is a novel and quite general reaction for these particular pinane derivatives. 

 All new compounds gave satisfactory spectral and microanalytical data. 



'"■'^dT" , and Magnus, P. D. 1976. Studies on terpenes. 4. Synthesis of 



optically active grandisol, the boll weevil pheromone. J. Am. Chem. 

 See. 98: 4594-4600. 

 (-)-B-Pinene was converted via the alcohol 26 into the ether 27 and, sub- 

 sequently, the lactone 28. Reduction of the lactone 28 with lithium tri- 

 ethoxy aluminum hydride gave 6,9-dimethyl-8-hydroxy-7-oxatricyclo[4.3.0.0^»"] 

 nonane (29). Treatment of the lactol 29 with triphenylmethylenephosphorane 

 gave the olefin 31 which was hydroborated using bis (3-methyl-2-butyl)borane 

 followed by alkaline hydrogen peroxide to give the diol 33. Dehydration cf 



