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The enantioselective de novo synthesis of pharmacologically important 14-hydroxy-6-oxomorphinans is described. 4,5-Desoxynaltrexone and 4,5-desoxynaloxone were prepared using this route and their biological activities against the opioid receptors were measured. [ABSTRACT FROM AUTHOR]

Enantioselective nickel-catalyzed reactions of (hetero)arylboronic acids or alkenylboronic acids with substrates containing an alkyne tethered to various acyclic electron-deficient alkenes are described. [ABSTRACT FROM AUTHOR]

A novel multicomponent coupling reaction involving the iridium-catalyzed 1,5-difunctionalization of 1,3-enynes with arylboronic acids and triazinanes is described. A key step in this 1,5-(aryl)aminomethylation reaction is the alkenyl-to-allyl 1,4-iridium(i) migration. [ABSTRACT FROM AUTHOR]

Nickel-catalyzed, highly diastereoselective annulations between activated allenes and 2-acetylarylboronic acid or 2-formylarylboronic acids are reported. No ligand for nickel is required, and the reactions proceed efficiently at room temperature to give a broad range of substituted 3-methyleneindan-1-ols. Preliminary results of an enantioselective variant are also described. [ABSTRACT FROM AUTHOR]

The synthesis of multisubstituted pyrroles by the nickel-catalyzed reaction of N-tosyl alkynamides with arylboronic acids is reported. These reactions are triggered by alkyne arylnickelation, followed by cyclization of the resulting alkenylnickel species onto the amide. The reversible E/Z isomerization of the alkenylnickel species is critical for cyclization. This method was applied to the synthesis of pyrroles that are precursors to BODIPY derivatives and a biologically active compound. [ABSTRACT FROM AUTHOR]

The enantioselective nickel-catalyzed desymmetrization of allenyl cyclohexa-2,5-dienones by reaction with arylboronic acids is described. Nickel-catalyzed arylation of the allene gives allylnickel species, which undergo cyclization by 1,4-allylation to produce hexahydroindol-5-ones and hexahydrobenzofuran-5-ones with three contiguous stereocenters in high diastereo- and enantioselectivities. [ABSTRACT FROM AUTHOR]

The synthesis of spiroindanes by the palladium-catalyzed oxidative annulation of non- or weakly activated 1,3-dienes with 2-aryl cyclic 1,3-dicarbonyl compounds is described. Examples of the dearomatizing oxidative annulation of 1,3-dienes with 1-aryl-2-naphthols are also presented. [ABSTRACT FROM AUTHOR]

Cu-catalyzed three-component couplings of vinylazaarenes, B2(pin)2, and N-Boc imines are described. Oxidation of the initially formed boronate gives azaarene-containing, Boc-protected amino alcohols with reasonable to good diastereoselectivities. [ABSTRACT FROM AUTHOR]

In the presence of substoichiometric Pd(OAc)(2), carboxylic acids undergo highly regio- and stereoselective additions to ynamides to provide α-acyloxyenamides., (This journal is © The Royal Society of Chemistry 2012)

A variety of cyclopropenes undergo direct silylation using (trifluoromethyl)trimethylsilane in the presence of a copper-bisphosphine catalyst; under these conditions, cyclopropenes that might otherwise undergo ring-opening are silylated efficiently.

Using cobalt catalysis, diethylzinc promotes the conjugate reduction of 4-acryloylmorpholine to produce the corresponding ethylzinc enolate, which reacts with N-tosyl aldimines to afford beta-aminoamides.