Gypsy moth, pheromone

This is the first example of a reaction for which the presence of a chelating ligand was observed to facilitate rather than retard metal-catalysed epoxidation (Gao et al., 1987). It was found that the use of molecular sieves greatly improves this process by removing minute amounts of water present in the reaction medium. Water was found to deactivate the catalyst. All these developments led to an improved catalytic version that allows a five-fold increased substrate concentration relative to the stoichiometric method. Sensitive water-soluble, optically active glycidols can be prepared in an efficient manner by an in situ derivatisation. This epoxidation method appears to be competitive with enzyme-catalysed processes and was applied in 1981 for the commercial production of the gypsy moth pheromone, (-1-) disparlure, used for insect control (Eqn. (25)). 

The substrate-controlled addition of 18 to 19 proceeded with good enantioselec-tivity and was used to prepare the epoxide (+)-dispalure, a gypsy moth pheromone.184... 

Show how organoborane intermediates can be used to synthesize the gypsy moth pheromone E, Z-CH3C02(CH2)4CH=CH(CH2)2CH=CH(CH2)3CH3 from hept-6-ynyl acetate, allyl bromide, and 1-hexyne. 

Commercial synthesis of the gypsy moth pheromone (7R,SS)-d sparlure by J. T. Baker ... 

This catalytic epoxidation method has been applied to the synthesis of a variety of natural products, particularly polyhydioxylated compounds, including carbohydrates (54) and macrolides. In addition, this reaction has been used for commercial synthesis of disparlure, a gypsy moth pheromone [J. T. Baker Co. (55) and the Shanghai Institute for Organic Chemistry (56)], and more importantly, glycidol, a versatile intermediate for synthesis of /3-blockers and other functionalized chiral molecules (Arco Co.) (Scheme 23) (57). 

In a demonstration of the synthetic utility of chiral y-alkoxy stannane reagents, Marshall and co-workers applied this methodology to the synthesis of the gypsy moth pheromones (+)- and (-)-disparlure [287]. The synthesis required the production of the [y-(alkoxy)allyl]stannane reagent 440 (Scheme 11-32). 

Figure 4.26 Structure of the gypsy moth pheromone. Modified by permission ofShokabo Publishing CoLtd...

Both the naturally occurring (7R, 8S) isomer of the gypsy moth pheromone disparlure (31) (sugar chain numbering) and its enantiomer... 

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