Biphenyl-1,2-diyl complexes

The dimerization of alkynes is a useful method for forming compounds such as enynes from simple alkynes [13]. The iridium-catalyzed dimerizahon of 1-alkyries was first reported by Crabtree, and afforded (Zj-head-to-head enynes using [Ir(biph)(PMe3)Cl] (biph = biphenyl-2,2 -diyl) as a catalyst [14]. Thereafter, an iridium complex generated in situ from [Ir(cod)Cl]2 and a phosphine ligand catalyzed the dimerizahon of 1-alkynes 1 to give (Tj-head-to-head enyne 2, fZj-head-to-head enyne 3, or 1,2,3-butatriene derivatives 4 in the presence of hiethylamine... 

Phosphine complexes such as IrCXt(PMe2Ph)2 are soluble in organic solvents 95 the hydrides,96 Ir(H)2Cl2(PR3)4, are photochemically reduced to Ir 1 species. Another unusual complex,97 [(Me3P)3Ir(biphBF)Cl]+, has a BF moiety inserted into the Ir—C bond of the biphenyl-2,2 -diyl group. 

Nitrilotriacetic acid, trisodium salt. See Trisodium NTA monohydrate Trisodium NTA 2,2, 2"-Nitrilotriethanol. See Triethanolamine 2,2, 2"-Nitrilotriethanol copper salt. See Copper-triethanolamine complex 2,2, 2"-Nitrilo [triethyl-tris (3,3, 5,5 -tetra-t-butyl-1,1 -biphenyl-2,2 -diyl) phosphite]... 

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