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A mild and solvent free protocol using FeCl3 supported on aerosil silica as catalyst allows the preparation of Diels—Alder cycloadducts from p-benzoquinones and simple dienes in high yields.

Treatment of metallic chalcogenolates generated in situ with aldehydes and various activated alkenes or alkynes allows an efficient and fast access to a number of γ-hydroxychalcogenides.

In this paper the preparation of reactive organometallics starting from organotellurides is reviewed. The application of the reactive organometallics prepared in this way in the synthesis of bioactive compounds is commented.

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

Current studies of oxazoline cyanocuprates addition to conjugated nitroalkenes, and their improved reactivity when compared to lithium oxazoline anions, has shown to be an efficient method for the synthesis of a variety of γ-nitrooxazolines, an interesting intermediate of γ-amino acids.

Lithium and magnesium organotellurolates were reacted with lactones producing the corresponding tellurocarboxylic acids. Treatment of the reaction mixture with lithium aluminum hydride allowed the isolation of the corresponding hydroxytellurides in a one-pot operation.

A C–O-dianionic zincate was generated by a Te/Li exchange reaction of an alkyltelluride, followed by Li/Zn transmetallation and reaction with methyllithium. The reaction between the enantiomerically pure (99% ee) (R)-dianionic zincate and benzoyl chloride led to 3-hydroxy-1-phenyl pentanone with total retention of the carbon configuration (99% ee). Similar results were obtained using the corresponding Lipshutz cyanocuprates.

n‐Butanethiol is generated in situ by sequential addition of n‐butyllithium and water to elemental sulfur. The n‐butanethiol formed was reacted with electron‐deficient olefines to give Michael‐type addition products in good yields. The method avoids the manipulation of the bad‐smelling n‐butanethiol.

1,4-C,O-dianions have been generated through concomitant acid/base and tellurium/lithium exchange reactions. The di-lithium salts were transmetallated with cerium chloride to the corresponding di-cerium salts and subsequently reacted with lactones and carboxylic acid anhydrides to yield the respective spiroketals. The di-lithium entities were also converted into the corresponding cyanocuprates that add in a 1,4-manner to 2-cyclohexen-1-one to form 1,6-dioxygenated compounds.

Reduction of (Z)-β-butyltelluro-enones gives the corresponding γ-hydroxy vinylic tellurides with retention of the double bond configuration. Reaction of γ-hydroxy vinylic tellurides with 2 equiv of n-butyllithium produces 1,4-C,O-dianions, which on reaction with carbon dioxide give the corresponding butenolides.

( Z )-β-Butyltellanyl α,β-unsaturated carbonyl compounds were stereoselectively produced by hydrotelluration of alkynones or by an addition/elimination sequence from enol tosylates. The β-butyltellanyl-enones were chemoselectively reduced with NaBH 4 /MeOH, NaBH 4 ·CeCl 3 ·7H 2 O/MeOH and DIBAL-H systems to the corresponding allylic alcohols with retention of the Z stereochemistry.

tert -Butyldimethylsilyl ethers of propargylic alcohols are hydrotellurated regioselectively to give 1,2- Z -vinylic tellurides. Enantiomerically pure propargylic alcohols give enantiomerically pure vinylic tellurides, which are coupled with alkynes under Pd catalysis to give enantiomerically pure allylic enynols.

An expeditious three-step synthesis of a mixture of stereoisomers of 5,9-dimethylpentadecane 1, the sexual pheromone of the coffee leaf miner Leucoptera coffeella, is described. The route employs an unsymmetrical double Wittig olefination to build the carbon skeleton of the molecule, as the key reaction. The bis-phosphonium salt 3, derived from 1,3-dibromopropane 2, reacted ‘one-pot’ with the ketones 2-octanone and 2-hexanone, affording the asymmetric diene 4. This was readily hydrogenated over Pd/C, furnishing pheromone 1 in 54% overall yield. Synthetic 1 showed high biological activity when tested in field experiments.

This paper describes the preparation of a series of oxazoline cuprates by reaction of an oxazoline lithium anion with copper(I) salts: CuBr.DMS, Cul and CuCN in THF solution. The oxazoline cyanocuprate showed the best reactivity using enones as electrophiles.