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1752785 
Journal Article 
[RuCl2(eta(6)-p-cymene)(P*)] and [RuCl2(kappa-P*-eta(6)-arene)] Complexes Containing P-Stereogenic Phosphines. Activity in Transfer Hydrogenation and Interactions with DNA 
Aznar, R; Grabulosa, A; Mannu, A; Muller, G; Sainz, D; Moreno, V; Font-Bardia, M; Calvet, T; Lorenzo, J 
2013 
1 
Organometallics
ISSN: 0276-7333
EISSN: 1520-6041 
32 
8 
2344-2362 
WOS:000318060400009 
The preparation of a series of half-sandwich ruthenium
complexes, [RuCl2(eta(6)-p-cymene)-(P*)] (P* = S-PMeRR') and [RuCl2(kappa-P*-eta(6)-arene)],
containing P-stereogenic phosphines is reported. The borane-protected P-stereogenic phosphines
have been obtained by addition of the (H3B)PMe2R (R = t-Bu (1), Cy (2), Pc (3))/sec-BuLi/(-)-
sparteine adduct to benzyl halides, carbonyl functions, and epoxides with yields between 40 and
90% and ee values in the 70-99% range. Those containing an aryl secondary function have been used
in the preparation of [RuCl2(eta(6)-p-cymene)-(P*)] complexes. Borane deprotection has been
performed using HBF4, except for (H3B)PRMe(CH2SiMe2Ph) phosphines, where DABCO was used to avoid
partial cleavage of the CH2-Si bond. In the case of (H3B)P(t-Bu)Me(CH2C(OH)Ph-2) (11) the
dehydrated phosphine was obtained. The tethered complexes were obtained by p-cymene substitution
in chlorobenzene at 120 degrees C, except for ferrocenyl-containing complexes, which decomposed
upon heating. The presence of substituents in the aryl arm of some of the phosphines introduces
new chiral elements in the tethered [RuCl2(x-P*-eta(6)-arene)] compounds. Full characterization
of all compounds both in solution and in the solid state has been carried out. Crystal structure
determinations of four phosphine borane molecules confirm the S configuration at the phosphorus
atom (1a,e,1 and 2d). Moreover, the crystal structure of one p-cymene complex (Si) and four
tethered complexes reveal the strain of the compounds with two atoms in the tether (7c,g,l and
8i). Tethering has a marked effect on the catalytic performance transfer hydrogenation of
acetophenone and on the nature of hydridic species originating during the activation period. The
chiral induction attains 58% ee with complexes with the bulkiest substituents in the pendant arm
of the phosphine. Three of the prepared complexes can interact with DNA and present a reasonable
cytotoxicity toward cancer cells. Intercalation of the free aromatic pendant arm of the
phosphines seems to be fundamental for such interactions.