57706-88-4Relevant articles and documents
Suga et al.
, p. 1335 (1966)
SELECTIVE HYDROGENATION OF 3,7-DIMETHYLOCTAEN-6-YN-1-OL-3
Matveeva, V. G.,Sul'man, E. M.,Ankudinova, T. V.
, p. 65 - 69 (1994)
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Ruthenium nanoparticle-intercalated montmorillonite clay for solvent-free alkene hydrogenation reaction
Upadhyay, Praveenkumar,Srivastava, Vivek
, p. 740 - 745 (2015/02/05)
Well-characterized, ruthenium nanoparticle-intercalated montmorillonite clay was used as a catalyst in solvent-free alkene hydrogenation reactions and the corresponding products were obtained in good yields. The catalytic activity of ruthenium nanoparticle-intercalated montmorillonite clay was successfully tested with 16 different functionalized and non-functionalized alkenes. Apart from alkene reduction, the ruthenium nanoparticle-intercalated montmorillonite clay was also tested in Wittig-type reactions for obtaining dehydrobrittonin A, an important intermediate for the synthesis of brittonin A. Ruthenium nanoparticle-intercalated montmorillonite clay was found to be active in the synthesis of dehydrobrittonin A and brittonin A. The ability to recycle the catalyst nine times, together with low catalyst loading, high catalytic activity and catalytic selectivity were noteworthy advantages of the proposed protocol.
Regioselective oxidation of nonactivated alkyl C-H groups using highly structured non-heme iron catalysts
Gómez, Laura,Canta, Merceì,Font, David,Prat, Irene,Ribas, Xavi,Costas, Miquel
, p. 1421 - 1433 (2013/03/29)
Selective oxidation of alkyl C-H groups constitutes one of the highest challenges in organic synthesis. In this work, we show that mononuclear iron coordination complexes Λ-[Fe(CF3SO3) 2((S,S,R)-MCPP)] (Λ-1P), Δ-[Fe(CF3SO 3)2((R,R,R)-MCPP)] (Δ-1P), Λ-[Fe(CF 3SO3)2((S,S,R)-BPBPP)] (Λ-2P), and Δ-[Fe(CF3SO3)2((R,R,R)-BPBPP)] (Δ-2P) catalyze the fast, efficient, and selective oxidation of nonactivated alkyl C-H groups employing H2O2 as terminal oxidant. These complexes are based on tetradentate N-based ligands and contain iron centers embedded in highly structured coordination sites defined by two bulky 4,5-pinenopyridine donor ligands, a chiral diamine ligand backbone, and chirality at the metal (Λ or Δ). X-ray diffraction analysis shows that in Λ-1P and Λ-2P the pinene rings create cavity-like structures that isolate the iron site. The efficiency and regioselectivity in catalytic C-H oxidation reactions of these structurally rich complexes has been compared with those of Λ-[Fe(CF3SO3) 2((S,S)-MCP)] (Λ-1), Λ-[Fe(CF3SO 3)2((S,S)-BPBP)] (Λ-2), Δ-[Fe(CF 3SO3)2((R,R)-BPBP)] (Δ-2), Λ-[Fe(CH3CN)2((S,S)-BPBP)](SbF6) 2 (Λ-2SbF6), and Δ-[Fe(CH3CN) 2((R,R)-BPBP)](SbF6)2 (Δ-2SbF 6), which lack the steric bulk introduced by the pinene rings. Cavity-containing complexes Λ-1P and Λ-2P exhibit enhanced activity in comparison with Δ-1P, Δ-2P, Λ-1, Λ-2, and Λ-2SbF6. The regioselectivity exhibited by catalysts Λ-1P, Λ-2P, Δ-1P, and Δ-2P in the C-H oxidation of simple organic molecules can be predicted on the basis of the innate properties of the distinct C-H groups of the substrate. However, in specific complex organic molecules where oxidation of multiple C-H sites is competitive, the highly elaborate structure of the catalysts allows modulation of C-H regioselectivity between the oxidation of tertiary and secondary C-H groups and also among multiple methylene sites, providing oxidation products in synthetically valuable yields. These selectivities complement those accomplished with structurally simpler oxidants, including non-heme iron catalysts Λ-2 and Λ-2SbF6.
