Indium-Mediated, Highly Efficient and Diastereoselective Addition of Cyclic Secondary Allylic Bromides to Carbonyl Compounds

Iron-mediated highly diastereoselective allylation of carbonyl compounds with cyclic allylic halides

An efficient iron-mediated highly diastereoselective allylation reaction of carbonyl compounds with cyclic allylic halides using a catalytic amount of bismuth(iii) chloride is reported.

Cyclopent-2-enylaluminium as allylzinc precursor for the diastereoselective allylmetallation of non-racemic imines: applications to the synthesis of enantiomerically enriched heterocycles

The generation of cyclopent-2-enylzinc from cyclopentadiene based on a titanium-catalyzed hydroalumination/transmetallation sequence is described. Applied to the allylmetallation of phenylglycinol-derived imines, this sequence leads to homoallylic amines with moderate to good stereoselectivities. The synthesis of disubstituted azetidines and piperidines illustrates the potential of the method.

Investigation of the aqueous transmetalation of π-allylpalladium with indium salt: the use of the Pd(OAc)2–TPPTS catalyst

pi-Allylpalladium complexes could be generated in water by the palladium(0) water soluble catalyst prepared in situ from palladium acetate and TPPTS. These complexes were transmetalated with indium to react with benzaldehyde. The aqueous solution of Pd(0)(TPPTS)(n) could be reused without deterioration of the catalyst in the first and second recycling. The system proved to be efficient with primary and secondary allylic substrates. The stereochemical outcome of the allylation through umpolung of allylpalladium, was also studied using models with a restraint conformation.

A Rapid and Stereoselective Route to the trans-Hydrindane Ring System

A short and stereoselective route to the trans-hydrindane derivative, a potential building block for the synthesis of steroidal and related molecules, was achieved by the operation of indium, tin, and ruthenium based reagents, starting from a tetrabromo norbornyl derivative.

Regio- and diastereoselective reduction of nonenolizable alpha-diketones to acyloins mediated by indium metal

[reaction: see text] Alpha-diketones are efficiently reduced with indium metal in methanol-water in the presence of NH(4)Cl, LiCl, or NaCl to give regio- and diastereoselectively the corresponding acyloins in good to excellent yield. The cleavage of the acyloins under Pb(OAc)(4)/MeOH-PhH condition provides a convenient and regioselective access to highly functionalized cyclopentane carboxaldehydes, potential building blocks in organic syntheses.

Indium metal as a reducing agent. Selective reduction of the carbon-carbon double bond in highly activated conjugated alkenes

[reaction: see text] Indium metal in aqueous ethanolic ammonium chloride reduces the C=C bond in highly activated conjugated alkenes such as alpha,alpha-dicyano olefins, beta-arylenones, and enone esters.