Syntheses and Structures of Ruthenium Complexes Containing a Ru-H-Tl Three-Center-Two-Electron Bond.

Treatment of CpRuH(PP) (PP=dppm, dppe) with TlPF6 produced [CpRu(H)(Tl)(PP)]PF6 . X-ray diffraction and computational studies suggest that the complexes contain a Ru-H-Tl 3c-2e bond and can be viewed as the first σ-complexes of period 6 main-group hydrides [CpRu{η2 -(H-Tl)}(PP)]PF6 or [Tl{η2 -H-RuCp(PP)}]PF6 . The complexes can be stored as a solid at room temperature for days without appreciable decomposition, but are unstable in solution and evolved to the trimetallic complexes [{CpRu(PP)}2 (µ-Tl)]PF6 .

RuH2(CO)(PPh3)3 catalyzed selective formation of 1,4-disubstituted triazoles from cycloaddition of alkynes and organic azides.

The ruthenium hydride complex RuH(2)(CO)(PPh(3))(3) was found to be an effective catalyst for the cycloaddition reactions of terminal alkynes and azides. In the presence of RuH(2)(CO)(PPh(3))(3), various azides reacted with a range of terminal alkynes to produce 1,4-disubstituted 1,2,3-triazoles with 100% selectivity and moderate to excellent yields.

Ruthenium-catalyzed regioselective deuteration of alcohols at the ß-carbon position with deuterium oxide.

A convenient method for regioselective H/D exchange between D(2)O and alcohols at the ß-carbon position using the catalytic system [(p-cymene)RuCl(2)]/ethanolamine/KOH is described. This method is applicable for deuteration of both primary and secondary alcohols. The H/D exchange reactions proceed through an oxidation/modification/reduction reaction sequence. Alcohols are first temporarily oxidized to carbonyl compounds by the hydrogen transfer catalyst. The carbonyl compounds then undergo deuteration at the carbon adjacent to the carbonyl group by keto-enol tautomerization in the presence of D(2)O and a catalytic amount of base. The deuterated carbonyl compounds are then reduced to produce deuterated alcohols. In support of the reaction mechanism, a well-defined bimetallic ruthenium complex was isolated from the reaction of [{(p-cymene)RuCl(2)}(2)] with ethanolamine. The activity of this complex is similar to that of [{(p-cymene)RuCl(2)}(2)]/ethanolamine.