The indium(III) selenolate obtained from indium(I) bromide and diphenyldiselenide promotes, alternatively, the Markovnikov hydroselenation, diselenation or hydration of terminal alkynes, depending on the experimental conditions. For many years, the interest in indium chalcogenates was related to their use as precursors of semiconductors type InE (E = chalcogene). 1 Only recently, it was demonstrated that some of these compounds can, conveniently, be used as useful reagents in organic transformations (Scheme 1). IIn(EPh) 2 (E = Se, Te) promotes the hydrochalcogenation of 2-alkyn-1-ol derivatives, in non-aqueous media, with rigorous regio-, and stereochemical control; the products correspond to Markovnikov adducts resulting of an anti addition of the chalcogenol constituents across the triple bonds. 2 IIn(SePh) 2 promotes the ring-opening reaction of epoxydes to the corresponding bhydroxy selenides with rigorous regioselectivity; the nucleophile incorporation at the less hindered carbon atom was observed for alkyl-substituted epoxides, and at the benzylic carbon atom for aryl derivatives. 3 Further, IIn(SePh) 2 was used to prepare unsymmetrical selenides from organyl halides. 4 Scheme 1 Organic reactions promoted by indium chalcogenatesContinuing our studies on the applications of indium compounds in organic synthesis, we examine here the hydroselenation of unactivated alkynes with indium(III) selenolates in aqueous media. We envisaged this reaction on observing that the compounds XIn(SePh) 2 (X = Br, I), prepared from InX and PhSeSePh in THF, MeCN or CH 2 Cl 2 and X 2 InSePh, obtained from InX and PhSeX in THF or CH 2 Cl 2 , readily decompose under moisture. Therefore, we first examined the nature of this decomposition. To a freshly prepared solution of Br 2 InSePh in THF, under N 2 atmosphere, was added an equivalent amount of 2,2¢-dipyridyl followed by a 5-fold excess of water; the resulting solution was allowed to contact with air. This treatment resulted in the slow deposition of colorless crystals of [Br 2 InOH(bipy)] 2 ·4THF (Scheme 2). 5 Benzeneselenol could not be isolated, since it was completely oxidized to diphenyldiselenide by air.Scheme 2 Decomposition of Br 2 InSePh by moisture [Br 2 InOH(bipy)] 2 ·4THF was characterized by X-ray means. 6 The compound, in the solid state, is a centrosymmetric dimer. The dimerization occurs through the hydroxylic oxygen atom, leading to a planar In 2 O 2 fourmembered ring. Two bromine and one bidentate 2,2-dipyridyl ligands complete the hexacoordination at each metal center. The geometrical arrangement around the indium centers is a distorted octahedron guarding a cis-relationship between each pair of similar ligands. The THF molecules are loosely held in the lattice and do not show any interaction with the indium complex. IIn(EPh) 2 + R-Y R-EPh CH 2 Cl 2 (E = Se; Y = Cl, Br, I, R = alkyl, benzyl, allyl, etc.) H EPh OH R 2 R 3 (E = Se, Te; R 1 , R 2 , R 3 = alkyl and aryl) i ii iii SePh In Br Br H 2 O bipy 2 O In O In Br Br Br Br H H bipy bipy 2 InBr + 2 BrSePh THF O...

The palladium-catalyzed allylation of N-tert-butanesulfinyl imines with allylic alcohols in the presence of InI as reducing reagent takes place with high diastereoselectivity in reasonable yields. The reaction with crotyl alcohol is totally regioselective, leading to the antidiastereomer as the main reaction product.The stereoselective allylation of imines using organometallic compounds is of great interest in synthetic organic chemistry because the resulting homoallylic amines are valuable building blocks. 1 For instance, the double bond of the allylic moiety can participate in a number of further synthetically useful transformations: hydroboration, hydration, epoxidation, hydroformylation, ozonolysis, olefin metathesis, etc. 2 Among the stereoselective methodologies, the catalytic enantioselective allylations 3 rely on the use of chiral Lewis acids or chiral Lewis bases. In addition, double activation could be also achieved by using chiral bifunctional catalysts 4 by the simultaneous activation of both electrophilic and nucleophilic reaction partners through a cooperative action of different functionalities of the ligand. However, and in spite of the rapid evolution of catalytic methods in recent years, the use of stoichiometric reagents (including substrates and/or allylic organometallic partners) is still the favourite choice of organic chemists in the synthesis of key intermediates of natural products. In these diastereoselective allylations, 5 the stereochemical information can be transferred by substrate control, including chiral auxiliaries, or through the use of chiral reagents (reagent control). Sometimes a double induction could also be involved in the process, a match/mismatch effect being possible. Performing the stereoselective allylation of imine derivatives with allylic halides in the presence of reducing metals under Barbier-type reaction conditions (metalation in the presence of the electrophile) is also of interest, because this strategy circumvents the need of isolating allyl metal species (the real nucleophiles), which usually are sensitive, and in many cases also toxic. The most commonly used metals in these transformations are chromium, 6 indium 7 and zinc. 8 Particularly noteworthy is the use of allylic alcohols as allylating reagents of carbonyl compounds and imines under palladium catalysis in the presence of a reducing reagent. 9 More recently, the use of the Kulinkovich reagent in the coupling of allylic alcohols with aldimines provides an alternative approach to regio-and stereodefined homoallylic amines. 10 On the other hand, in the growing field of the synthetic applications of chiral N-tert-butanesulfinyl derivatives, 11 we reported the diastereoselective allylation 12 of N-tert-butanesulfinyl aldimines 13 and ketimines 14 with in situ generated allylindium reagents, and the first one-pot a-aminoallylation of aldehydes with chiral tert-butanesulfinamide, allylic bromides, and indium, which provides homoallylic amines with high chemoand stereoselectivities. 15 The chiral auxiliar...

We present here carbon-nitrogen bond formation via a coupling reaction of 2-iodo-selenophene catalyzed by Cu(I) in the presence of a base and an inexpensive ligand, and establish the first route to obtaining 2-nitrogen-selenophene derivatives in good yields. We can anticipate that this reaction works well with oxazolidinones, lactams, and aliphatic and aromatic amides, as nitrogen sources, in the absence of any supplementary additives. In addition, the reaction proceeded cleanly under mild reaction conditions and was sensitive to the ratio of amide/2-iodo-selenophene, as well as the nature of the ligand, base, and solvent.

Indium(III) benzenechalcogenolates (chalcogen = sulfur and selenium) promote the rigorous Markovnikov hydrochalcogenation of terminal alkynes. The generality and limitations of the reaction with aminoalkynes leading to allylic amines bearing vinylic chalcogenide substituents are discussed.

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