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We present a general protocol for the cross-coupling reaction of Grignard reagents and organic tellurides. Aryl Grignard reagents react stereospecifically with vinyl tellurides in the presence of a catalytic amount of manganese (II) chloride and copper (I) iodide to produce good yields of the corresponding cross-coupling products.

The total synthesis of (−)-Blastmycinolactol, (+)-Blastmycinone, (−)-NFX-2, and (+)-Antimycinone was accomplished in few steps in high yields and ee, starting from enantiomerically enriched ( S )- Z -vinylic hydroxytellurides.

The components of the pheromone blend of Mayetiola destructor, Drosophila mulleri, and Contarinia pisi were synthesized in high enantiomeric excess (99% ee) from a common enantiopure dianion prepared from an enantiopure hydroxytelluride.

The vinylic telluride (2a) and phenyl magnesium chloride (1a) were employed as model compounds to determine the best reaction conditions. The use of MnCl2 (20 mol %) or CuI (20 mol %) alone promotes the cross-coupling reaction in low yield (10 % and 30 % respectively). When a mixture of MnCl2/CuI (20/20 or 10/10 mol %) was used, the homo-coupling reaction of the Grignard reagent (1a) was observed. This side reaction was suppressed by using 5 mol % of each metal salt (MnCl2/CuI). Under this conditions the product (3a) was obtained in 78 % yield. As can be observed in Scheme 2 an inversion of the olefin configuration was observed. The above conditions were employed to promote the cross-coupling of others Grignard reagents 1 and vinylic tellurides 2 giving the products in 50-79 % yields as can be observed in Scheme 3.

We present a general protocol for the cross-coupling reaction of Grignard reagents and organic tellurides. Aryl Grignard reagents react stereospecifically with vinyl tellurides in the presence of a catalytic amount of manganese (II) chloride and copper (I) iodide to produce good yields of the corresponding cross-coupling products.

The naturally occurring butanolides (−)-blastmycinolactol, (+)-blastmycinone, (−)-NFX-2, (+)-antimycinone as well as the four stereoisomers of the butenolide Acaterin were prepared in high enantiomeric purity using hydroxy-vinyl tellurides as starting materials.

Starting from (Z)-vinylic hydroxytellurides (I), a straightforward synthesis of the title compounds is carried out.