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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.

Acaterin 1 (1) is an inhibitor of Acylcoenzyme A cholesterol acyl transferase (ACAT). It was first isolated from a culture of Pseudomonas sp. This type of inhibitor has a promising role in the treatment of atherosclerosis. The butenolide skeleton with an α-alkyl chain, can be obtained from γ-butyl-telluro-allylic alcohols by Te/Li exchange reaction and capture with CO2 according to a methodology recently established in our group. 2

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.

A homoenolate generated by tellurium/lithium exchange reaction was employed in a straightforward enantioselective synthesis of (+)-endo-brevicomin in 70% yield and 84.4% e.e. Um homoenolato gerado pela reação de troca telúrio/lítio foi aplicado na síntese enantioseletiva do (+)-endo-brevicomin com 70% de rendimento isolado e 84,4% de e.e.