We have found the first reaction of direct cupration of fluoroform, the most attractive CF(3) source for the introduction of the trifluoromethyl group into organic molecules. Treatment of CuX (X = Cl, Br, I) with 2 equiv of MOR (M = K, Na) in DMF or NMP produces novel alkoxycuprates that readily react with CF(3)H at room temperature and atmospheric pressure to give CuCF(3) derivatives. The CuCl and t-BuOK (1:2) combination provides best results, furnishing the CuCF(3) product within seconds in nearly quantitative yield. As demonstrated, neither CF(3)(-) nor CF(2) mediate the Cu-CF(3) bond formation, which accounts for its remarkably high selectivity. The fluoroform-derived CuCF(3) solutions can be efficiently stabilized with TREAT HF to produce CuCF(3) reagents that readily trifluoromethylate organic and inorganic electrophiles in the absence of additional ligands such as phenanthroline. A series of novel Cu(I) complexes have been structurally characterized, including K(DMF)[Cu(OBu-t)(2)] (1), Na(DMF)(2)[Cu(OBu-t)(2)] (2), [K(8)Cu(6)(OBu-t)(12)(DMF)(8)(I)](+) I(-) (3), and [Cu(4)(CF(3))(2)(C(OBu-t)(2))(2)(μ(3)-OBu-t)(2)] (7).

The reaction of 1,2,4-trimethyltriazolium tetrafluoroborate ([LH 2 ](BF 4 ) 2 ) with several metal precursors provides a series of homo-and heterodimetallic compounds of Rh and Ir. The reaction of [LH 2 ](BF 4 ) 2 with [Cp*IrCl 2 ] 2 in the presence of NaH in MeOH yields the monocarbene complex [Cp*Ir(LH)Cl 2 ](BF 4 ), which is a very convenient synthon to the preparation of heterodimetallic species through the deprotonation of the remaining NCHN group. Three crystal structures of dimetallic compounds of di-iridium(III), iridium(III)/iridium(I), and iridium(III)/rhodium(I) are described. The complexes obtained have been tested in a tandem catalytic reaction implying the consecutive oxidative cyclization of 2-aminophenyl ethyl alcohol and the alkylation of the resulting imidazole with a series of primary alcohols. The new catalysts show high activity in the overall reaction process, and the selectivity in the production of the bisindolylmethane or monoalkylated indole is tuned by changing the indole/alcohol molar ratio.⊥ This article is dedicated to Prof. Robert H. Crabtree on the occasion of his 60th birthday.

The ligand 1,2,4-trimethyl-triazolyl-diylidene has been used for the preparation of a series of three iridium/palladium heterometallic complexes that have been fully characterized. The presence of the two different metals allows tandem processes to be designed by combining reactions that are typically catalyzed by Ir and Pd. Three tandem reactions have been studied: dehalogenation/transfer hydrogenation of haloacetophenones, Suzuki-coupling/transfer hydrogenation of p-bromoacetophenone, and Suzuki-coupling/alpha-alkylation of p-bromoacetophenone. All three reactions yielded excellent outcomes to the corresponding final products, with the relevant feature that the heterodimetallic complexes are more active than the sum of the corresponding homodimetallic species. All three catalytic reactions reported here constitute unprecedented examples of tandem approaches to complex organic molecules.

The trinuclear cationic zinc hydride cluster [(IMes)3Zn3H4(THF)](BPh4)2 (1) was obtained either by protonation of the neutral zinc dihydride [(IMes)ZnH2]2 with a Brønsted acid or by addition of the putative zinc dication [(IMes)Zn(THF)](2+). A triply bridged thiophenolato complex 2 was formed upon oxidation of 1 with PhS-SPh. Protonolysis of 1 by methanol or water gave the corresponding trinuclear dicationic derivatives. At ambient temperature, 1 catalyzed the hydrosilylation of aldehydes, ketones, and nitriles. Carbon dioxide was also hydrosilylated under forcing conditions when using (EtO)3SiH, giving silylformate as the main product.

Triphenylborane (BPh3 ) in highly polar, aprotic solvents catalyzes hydrosilylation of CO2 effectively under mild conditions to provide silyl formates with high chemoselectivity (>95 %) and without over-reduction. This system also promotes reductive hydrosilylation of tertiary amides as well as dehydrogenative coupling of silane with alcohols.

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A set of three different NHC-Pd-pyridine complexes (NHC=1,2,4-trimethyltriazolyldiylidene, 1,3-dimethylimidazolylidene, and 1,4-dimethyltriazolylidene) have been prepared and fully characterized. The X-ray molecular structures of two of the complexes are reported. The three complexes have been tested in a series of reactions between o-hydroxyaryl halides and phenylacetylene to afford benzofurans, in a tandem process that comprises a Sonogashira coupling followed by a cyclic hydroalkoxylation. All three catalysts afforded excellent yields of the final products when the corresponding iodoarenes were used.

Our recently described 1,2,4-trimethyltriazolyldiylidene ligand (ditz) has been coordinated to two different palladium sources, namely, Pd(OAc)2 and Pd(acac)2, affording two different complexes that have been fully characterized. Remarkably, the product from the reaction with Pd(acac)2 shows activation of the C−H bonds of two terminal methyl groups of the acac ligands of Pd(acac)2, affording a 12-membered metallacycle with three palladium centers. The reaction product from the reaction with Pd(AcO)2 was shown to be an efficient catalyst in C−C coupling reactions, such as the Heck reaction and the acylation of aryl halides with aldehydes.