Pheromones boll weevil

Ketone (27) was needed for a synthesis of the boll weevil pheromone (28), Suggest a synthesis of (27) using Birch reduct ion,... 

Nickel(0)-catalyzed dimerization of isoprene (3 2-methylbuta-l.3-diene) has been used as the key step in the synthesis of (+)-grandisol (8), a male boll weevil pheromone. It is interesting to note that the cyclobutane 4 was formed by unsymmetrical and head-to-head cyclodimerization and that cycloadduets 5-7 were also formed in this transformation.9... 

Grandisol has previously been synthesized using a number of photochemical procedures. Two recent reports demonstrate the utility of the copper catalyzed photocycloaddition (see Sch. 28) in the synthesis of the four member ring observed in the boll weevil pheromone. The first example [41] is a chiral synthesis and the second pathway [42] provides the racemic product. 

The skeleton can be synthesized from myrcene (7) (brominative cyclization was mentioned in Vol. 4, p. 534, Ref. 583), either by reaction with benzenesulfenyl chloride (giving 719), or by epoxidation (to 720) before cyclizing with SnCl4 or trifluoroacetic acid. The cyclized products 721 (R = OCOCF3 or Cl, R = OH or SPh) were converted to the boll-weevil pheromone 722 (R... 

The Norrish Type I fragmentation of the cyclic ketone (178) has been used in a synthesis of grandisol (179), a major component of the male boll weevil pheromone.125 The cleavage reaction gave the aldehyde (180) which was subsequently decarbonylated to give the desired product. 

Fig. 27.2 Pheromone structures of some groups of moth and beetle pests. The names of the chemical structures in the blend of boll weevil pheromone components (2e) are (Z)-2-(3,3, dimethyl)-cyclohexylideneethanol (grandlure II) and (Z)-(3,3-dimethyl)-cyclohexylideneacetalde-hyde (grandlure HI). The chemical name of S-rhynchophorol (2f) is 4S-( )-6-methyl-2-hepten-4-ol. From The Pherobase (http //www.pherobase.com)...

Ridgway RL, Inscoe MN, Dickerson WA (1990) Role of the boll weevil pheromone in pest management. In Ridgway RL, Silverstein RM, Inscoe MN (eds) Behavior-modifying chemicals for insect management. Marcel Dekker, New York, pp 437 172... 

Hedin, P.A. A Study of Factors that Control Biosynthesis of the Compounds which Comprise the Boll Weevil Pheromone. J. Chem. Ecol. 3, 279-289 (1977). 

Levoglucosenone 1 has provided a starting point for the synthesis of cyclobutane 3 which constitutes a formal total synthesis of the boll weevil pheromone, (+)-grandisoL Methylatirai of 1 to give 2 was achieved as shown in Scheme 1 and the cyclobutane unit was established via intramolecular enolate alkylation. 

Hedin 458) has recently summarized factors that influence the biosynthesis of the boll weevil pheromone complex. Total synthesis was at a maximum during the summer and a minimum during the winter. In this study Hedin 458) did two types of experiments. The first series exposed 10-day-old adult weevils to a saturated atmosphere of a number of terpene hydrocarbons. It was found that only myrcene and limonene produced detectable amounts of oxygenated substances and that males produced more than females. No compounds isolated suggested that the weevils are capable of cyclizing alicyclic terpenes or their pyrophosphates. 

Zurfluh, R., L. L. Dunham, V. L. Spain, and J. B. Siddall Synthetic studies on insect hormones. IX. Stereoselective total synthesis of a racemic boll weevil pheromone. J. Amer. Chem. Soc. 92,425- 27 (1970). 

Bedoukian, R. H., and J. Wolinsky Biogenetic type synthesis of cyclohexyl constituents of the boll weevil pheromone. J. Org. Chem. 40, 2154— 2156 (1975). 

Hedin, P. A. A study of factors that control biosynthesis of the compounds which comprise the boll weevil pheromone. J. Chem. Ecol. 3,279—289 (1977). 

Hedin, P. a., R. C. Gueldner, and A. C. Thompson Utilization of the boll weevil pheromone for insect control. In M. Beroza, Ed., Pest Management with Insect Sex Attractants and other behavior-controlling chemicals. ACS Symposium Series N. 23. American Chemical Society, Washington, D. C. 1976. 

Mori, K. Synthesis of the both enantiomers of grandisol, the boll weevil pheromone. Tetrahedron 34,915—920 (1978). 

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