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Organochalcogen molecules have extensive applications in various fields. They serve as pharmaceuticals, ligands, organocatalysts, agrochemicals, and other functional materials. Difunctionalization of olefins, which belong to a class of multicomponent reactions, is a successful technique for introducing two functional moieties in a single‐step reaction, both in terms of atom economy and step economy. The difunctionalization of olefins with diorganyl dichalcogenides may effectively increase the molecular complexity, which has achieved significant advancements in recent decades. This article describes recent advancements in the difunctionalization of olefins with diorganyl diselenides and diorganyl disulfides. [ABSTRACT FROM AUTHOR]

The axially chiral monophosphine 2-(diphenylphosphino)-2'-methoxy-1,1'-binaphthyl (MeO-MOP) is a versatile ligand. We report a shorter (four steps from chiral BINOL), more atom-economical synthetic route to MeO-MOP. (R)-BINOL is transformed into its monomethyl ether by the Mitsunobu reaction, and the latter is reacted with triflic anhydride to give its triflate. The C-P coupling of the triflate and diphenylphosphine oxide catalyzed by palladium give a phosphine oxide, the precursor of (R)-MeO-MOP, which is reduced with trichlorosilane to furnish (R)-MeO-MOP. [image omitted] [ABSTRACT FROM AUTHOR]

H8-MonoPhos, a new stable and easily prepared monodentate phosphoramidite ligand, has been synthesized from H8-BINOL. The ligand showed extremely highly enantioselectivity of higher than 99.9% e.e. in the asymmetric Rh-catalyzed hydrogenation of α-dehydroamino acids. Our study further supports the new concept that there is no gap in efficiency and enantioselectivity between monodentate and chelating ligands for asymmetric catalysis. [Copyright &y& Elsevier]

Abstract: A catalyst based on a new biarylphosphine ligand (3) for the Pd-catalyzed cross-coupling reactions of amides and aryl chlorides is described. This system shows the highest turnover frequencies reported to date for these reactions, especially for aryl chloride substrates bearing an ortho substituent. An array of amides and aryl chlorides were successfully reacted in good to excellent yields. [Copyright &y& Elsevier]

Abstract: Many synthetic methods of racemic N-aryl (including N-(2-haloaryl)) α-amino acid amides have been reported, but there are only a few for eutomers and none for inactivated halo(hetero)arenes. Selective C–N coupling of aliphatic amino group of α-amino acid amides is a direct and valuable method, but still unresolved. Here we disclose a simple and cheap ligand-free CuI-catalyzed selective synthesis of chiral N-(2-halo(hetero)aryl) amino acid amides without obvious racemization. A rational mechanism is proposed. [Copyright &y& Elsevier]

The reaction proceeds without obvious racemization. [ABSTRACT FROM AUTHOR]

Generally the reactivity of aryl-/heteroaryl-/styryl-halides is I < Br < Cl. [ABSTRACT FROM AUTHOR]