Alkyne and alkene complexes of (tetramesitylporphyrinato)ruthenium(II)

Abstract

The reactions of benzene or toluene solutions of RuII(TMP), where TMP is the dianion of 5,10,15,20–tetramesitylporphyrin, with some acetylenes and alkenes are reported. Acetylene yields the isolable [Ru(TMP)]2(μ-C2H2) species; while with phenylacetylene or diphenylacetylene, 1:1 π-complexes are formed. The π-complexes Ru(TMP)(C2H4) and Ru(TMP)-(C2H4)(iPrOH)•iPrOH are isolated from reactions with ethylene, and a similar cyclohexene species is characterized insitu. The findings are relevant to O2-epoxidation of alkenes catalyzed by the trans-Ru(TMP)(O)2 complex. Keywords: ruthenium, porphyrin (tetramesityl), alkene complexes, alkyne complexes.

Acetylenes Rearranging on Ruthenium-Porphyrinogen and Leading to Vinylidene and Carbene Functionalities

“…Herein we report how we synthesized the [Ru=C=CHR] unit by acetylene rearrangements2, 6 in the reaction with 1 (see Scheme ), and how we then converted the [Ru=C=CHR] unit into a variety of carbene and metallacumulene structures 2, 6. The paper most related to our work reports the reaction of Ru–porphyrin with ethyne to produce a μ ‐biscarbene 7. Although these functionalities have various precedents in the case of cyclopentadienyl, phosphine, arene,2, 6, 8 and some amine9 ligands, they are absent in the macrocyclic ruthenium chemistry.…”

“…The characterization of 5 (RuÀC 1.80(1), CÀOMe 1.38( 1) ) and 6 is given in the Supporting Information. The reaction of 2 with H 2 O follows the pathway shown for the other protic substrates (Scheme 1, intermediates B and C), [2, 6c] except that the final compound (7) has an acyl functionality which has been formed in conjunction with the oxidation of Ru II to Ru III , as depicted in Scheme 1. The complex is paramagnetic (m eff 1.85 BM at 293 K, n Ä CO 1577 cm À1 ), and has been characterized in the solid state by X-ray analysis (RuÀC 1.91(1), CO 1.24(1) ).…”

“…[2,6] The paper most related to our work reports the reaction of Ru ± porphyrin with ethyne to produce a m-biscarbene. [7] Although these functionalities have various precedents in the case of cyclopentadienyl, phosphine, arene, [2,6,8] and some amine [9] ligands, they are absent in the macrocyclic ruthenium chemistry. The parent Ru-meso-octamethylporphyrinogen 1 [10] was prepared according to the known procedure for this class of compounds.…”

“…Acetylene and phenylacetylene react smoothly with 1 to form 2 and 3, [10] respectively. Complexes 2 and 3 have been fully characterized, including the X-ray analysis of 2 (RuC 1.738(5), CC 1.356 (7) ). [2a] Unlike in the reactions reported for the conventional Ru ± organometallic fragments, [2,6,8] the reaction discussed here, possibly, proceeds by a different pathway, which does not involve in a preliminary stage any h 2 complexation of the alkyne.…”

Complexes of Ruthenium and Osmium Containing η2–η6 Hydrocarbon Ligands: (i) Complexes not Containing Cyclobutadiene, Cyclopentadienyl or η-Arene Coligands

“…I n contrast, the 2:1 complex with ethyne is formulated as a bis(carbene), [{RU(TMP)} 2 (T|-C 2 H 2 )]. 66 The ] to the corresponding stable, blue or green, paramagnetic ruthenium(III) complexes in which the double or triple bond is still coordinated. 78 Silaethene complexes have been implicated in the selective H-D exchange of alkylsilanes with C 6 D 6 catalysed by [OsH(SiMe 2 R)(PMe 3 ) 4 ] (R = Me, Et) 79 and in the disproportionation of alkylsilanes catalysed by [RuH 3 (TMS)(PMe 3 ) 3 ].…”