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The new and easily prepared OTips-DalPhos ligand (L1) offers broad substrate scope at relatively low loadings in the palladium-catalyzed C-N cross-coupling/cyclization of o-alkynylhalo(hetero)arenes with primary amines, affording indoles and related heterocyclic derivatives in high yield.

The synthesis of indoles via the metal-catalyzed cross-coupling of ammonia is reported for the first time; the developed protocol also allows for the unprecedented use of methylamine or hydrazine as coupling partners. These Pd/Josiphos-catalyzed reactions proceed under relatively mild conditions for a range of 2-alkynylbromoarenes., (This journal is © The Royal Society of Chemistry 2011)

The versatile new ligand precursor 1/3-P(i)Pr(2)-2-S(t)Bu-indene has been employed in the preparation of neutral and cationic (kappa(2)-P,S)Pt(benzyl) complexes, as well as structurally related zwitterions in which the formally cationic metal fragment is counterbalanced by an uncoordinated indenide or borate fragment that is contained within the ancillary ligand backbone.

Whereas a new coordinatively unsaturated Cp*Ru(kappa(2)-P,O) complex (1a) forms adducts with two-electron donors (including sigma-H(2) and mu-N(2) ligands), double Si-H bond activation is observed upon treatment with Ph(2)SiH(2) or PhSiH(3), leading to the clean formation of products corresponding to the net insertion of a Ph(2)Si: or Ph(H)Si: fragment into the Ru-O bond of 1a.

Silver triflate, either alone or in the presence of an appropriate phosphine or NHC ligand, has been shown to catalyze the chemoselective hydrosilylation of aromatic and aliphatic aldehydes to yield silyl ethers, thus representing the first systematic application of silver species as catalysts for the hydrosilylation of unsaturated organic substrates.

Inspired by the monodentate P,N ligation strategy featured in Crabtree's catalyst [(COD)Ir(PCy3)(Py)]+PF6-([1]+PF6-), a new class of bidentate cationic ([2]+X-) and zwitterionic (3) Ir complexes have been developed, which are capable of mediating the hydrogenation of alkenes under mild conditions and in a wider range of solvents than is possible for [1]+PF6-.

A new indene-based ligand featuring pendant phosphine sulfide and amine donor fragments has been developed; Rh(I) coordinates to the neutral form of the ligand in a kappa2-[N,S] fashion, while the anionic form of the ligand binds Rh(I) and Mn(I) in kappa2-[C,S] and eta5 modes, respectively.