The chemistry of the carbon-transition metal double and triple bond: Annual survey covering the year 2008

Cationic abnormal N-heterocyclic carbene ruthenium complexes as suitable precursors for the synthesis of heterobimetallic compounds

Heterobimetallic dicarbene compounds are easily prepared from cationic imidazolyl-based abnormal N-heterocyclic carbene ruthenium complexes which allow facile metallation.

Rhodafuran from a methoxy(alkenyl)carbene by the rhoda-1,3,5-hexatriene route

A methoxy(alkenyl)carbenerhodium complex [RhCp*Cl{[double bond, length as m-dash]C(OMe)CH[double bond, length as m-dash]CPh2}(PMe3)]PF6 (2) has been synthesized and used as the starting material for the study of the effect of the metal center (Rh vs. Ir) in the formation of new rhodacycle complexes. While η3 and η5 indenylrhodium complexes have been achieved by the C-H bond activation of a phenyl ring, insertion of terminal alkynes into the rhodium-carbene bond led to the first example of the synthesis of rhodafuran complexes through rhoda-1,3,5-hexatriene intermediates. This new method represents an efficient process to obtain metallafuran complexes.

Synthesis of C14–C21 acid fragments of cytochalasin Z8via anti-selective aldol condensation and B-alkyl Suzuki–Miyaura cross-coupling

An efficient synthesis of the C14–C21 acid fragment of cytochalasin Z₈ was accomplished in 10 steps with 14% overall yield.

Cyclic bent allene hydrido-carbonyl complexes of ruthenium: highly active catalysts for hydrogenation of olefins

A new family of ruthenium complexes bearing the carbodicarbene-type ligand "cyclic bent allene" (CBA) have been synthesized from the common precursor RuHCl(CO)(PPh3)3. Complexes were evaluated for catalytic activity in the room-temperature hydrogenation of unactivated olefins and were found to be significantly more active than known ruthenium hydrido-carbonyl phosphine or NHC complexes. In particular, RuH(OSO2CF3)(CO)(SIMes)(CBA) was found to be among the most active hydrogenation catalysts, achieving comparable activity to Crabtree's catalyst in the hydrogenation of unactivated trisubstituted olefins and superior activity in the hydrogenation of styrene derivatives in side-by-side catalytic runs. RuH(OSO2CF3)(CO)(SIMes)(CBA) was also found to be highly active in olefin selective hydrogenation in the presence of a variety of unsaturated functional groups, and can achieve exceptional diastereoselectivity in functional-group-directed hydrogenations at very low catalyst loadings.

Ru–Ag and Ru–Au dicarbene complexes from an abnormal carbene ruthenium system

The first complexes containing an anionic dicarbene connected to two different d-block elements are reported. The synthetic pathway entails metalation and transmetalation reactions, starting from a cationic abnormal Ru-NHC complex.

Preparation of pyranylidene complexes of ruthenium

Dimerization of alkylpropiolate on the half-sandwich fragment [Ru(η⁵-C₅H₅)(PPh₃){P(OMe)₃}]⁺ affords pyranylidene derivatives.