Lobesia botrana pheromone

An excellent, general procedure for the stereoselective synthesis of conjugated 13,13 dienes utilizes 1-halo-l-alkynes and thexylborane (36). We prepared the compound XXXX (which is the 13,13 isomer of the Lobesia botrana pheromone XXIX) in >98% stereochemical purity by this procedure (Figure 19). 

Analysis of the sex pheromone glands of the female grapevine moths Lobesia botrana Denis and Schiffermuller (Lepidoptera Tortricidae),... 

The preparation of conjugated dienes from pyridines is exemplified by the transformation of 2-picoline into the sex pheromone (669) of Lobesia botrana, a major pest of vineyards (Scheme 154) (80TL67). Thus, the lithio salt of 2-picoline was alkylated by 2-(5-chloropentyl-oxy)tetrahydropyran, the resulting pyridine (665) N-methylated, and the pyridinium salt reduced by sodium borohydride. Quaternization of the 1,2,3,6-tetrahydropyridine (666) and Hofmann elimination gave the (7 , 9Z)-undecadien-l-ol (667) as the sole isomer. Protection of the alcohol and treatment of the corresponding ammonium salt (668) of the amine with lithium dimethylcuprate gave pure (669) after hydrolysis, acetylation and HPLC purification. 

Hydroboration/protonolysis of ( )-enynes completes a route to (E, Z)-dienes. For example, the ( )-enyne generated in Figure B4.6 was converted into (IE, 9Z)-7,9-dodecadien-l-yl acetate (a natural sex pheromone of the European grape vine moth Lobesia botrana) by hydroboration with Sia2BH followed by acetic acid protonolysis (Equation B4.7). 

Many insect pheromones have conjugated cis, trans-diene system l52, l53). The versatility of these reactions is exemplified in the synthesis of many natural products l53-154, 55 In Eq. 99, the four step synthesis of a natural sex pheromone of the European grape vine moth (Lobesia botrana), (7E, 9Z)-7,9-dodecadien-l-yl acetate, is illustrated 155). 

Recently, Rossi et al. have applied the cross-coupling of 1-alkenylboranes with 1-alkynyl halides for the synthesis of natural products. Thus, (7 , 9Z)-7,9-dodecadien-1-yl acetate (32), the sex pheromone of Lobesia botrana, has been synthesized by the following sequence involving ... 

This method is very useful for synthesis of such compounds on a moderate scale. We have applied it to the preparation of a number of (Z E) - and (E,Z) -1, 3-dienes including the pheromone of Lobesia botrana, (XXIX). 

El-Sayed AM, Godde J, Witzgall P, Arn H (1999) Characterization of pheromone blend for grapevine moth, Lobesia botrana by using flight track recording. J Chem Ecol 25 389-400... 

The most effective application technique for lepidopteran species is to permeate the atmosphere with synthetic pheromone, and to thereby prevent olfactory communication and mate finding. The mating disruption technique has been successfully applied in Europe to three lepidopteran insects from horticultural crops codling moth Cydia pomonella, and the grape berry moths Eupoecilia ambiguella and Lobesia botrana [132, 133]. 

Protonolysis of alkenylboranes generates an alkene and this reaction is faster than the analogous protonolysis of alkylboranes.57 Once again, protonolysis proceeds stereospecifically with retention of configuration. In Negishi s synthesis of the sex pheromone of Lobesia botrana (65), hydroboration of 64 was followed by protonolysis with acetic acid at 0°C to give 65, for a net conversion of an alkyne to an alkene.58 As with alkylboranes, protonolysis of vinylboranes with deuteroacetic acid allows the synthesis of deuterated alkenes. 

Negishi and Abramovitch have described an extremely elegant use of two generations of Brown chemistry in the four-step synthesis of the insect sex pheromone of the European grape vine moth Lobesia botrana, (7E,9Z)-dodeca-7,9-dien-l-yl acetate (101). The now familiar acetylene zipper reaction converts (102) into (103), the terminal acetylene (103) produced being then coupled via the borane (104) to give the ( )-dodec-7-en-9-yn-l-yl acetate (105) in >99% isomeric purity and in 70% yield. Hydroboration then leads to the desired product (Scheme 26). 

The pheromones of the vine moths (Eupoecilia ambiguella and Lobesia botrana) are typical for the sex attractants used by the large families of tortrix moths (Tortricidae) and owlet moths (Noctuidae) (Fig. 8.78). 

Ac [55774-32-8]. Isol. from the abdomen of Lobesia botrana females. Pheromone for various moths, particularly L. botrana. Bpo.2 86-86.5 . 

A number of conjugated dienes have been identified as sex pheromones. Among these are (8 ,10 )-8,10-dodecadien-l-ol (475, Scheme 84) from the codling moth (Laspeyresia pomonella), (7 , 9Z)-7,9-dodecadien-1-yl acetate (490, Scheme 86) from the European grapevine moth (Lobesia botrana), ( )- and (Z)-9,ll-dodecadien-l-yl acetates (518a and 518b, respectively, see Scheme 90) from the red bollworm moth (Diparopsis castanea), and (10 , 12Z)-10,12-hexadecadien-l-ol (498, Scheme 87) from the silkworm moth (Bombyx mori). 

Negishi, E. L, and A. Abramovitch A highly efficient chemoselective, regio-selective, and stereoselective synthesis of (7 ,9Z)-dodecadien-l-yl acetate, a sex pheromone of Lobesia botrana, via a functionalized organoborate. Tetrahedron Lett. 1977, 411—414. 

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