Design and synthesis of fused polycycles via Diels–Alder reaction and ring-rearrangement metathesis as key steps

• Sambasivarao Kotha and
• Ongolu Ravikumar

Beilstein J. Org. Chem. 2015, 11, 1259–1264, doi:10.3762/bjoc.11.140

• ; HRMS (Q–ToF) m/z: [M + Na]+ calcd for C25H32NaO2, 387.2295; found, 387.2292. Commercially available ruthenium catalysts used in RRM metathesis. Crystal structure of 5 with thermal ellipsoids drawn at 50% probability level. Synthesis of hexacyclic compound 6a by using an RRM approach. Synthesis of

Recent advances in transition metal-catalyzed Csp²-monofluoro-, difluoro-, perfluoromethylation and trifluoromethylthiolation

• Grégory Landelle,
• Armen Panossian,
• Sergiy Pazenok,
• Jean-Pierre Vors and
• Frédéric R. Leroux

Beilstein J. Org. Chem. 2013, 9, 2476–2536, doi:10.3762/bjoc.9.287

• . Kamigata et al. in the case of ruthenium catalysts, where isomeric mixtures of α- and β-functionalized pyrroles were produced [101][104]. In 2001, Q.-Y. Chen and coworkers also reported a nickel-catalyzed methodology, with perfluoroalkyl chlorides as perfluoroalkylating reagents and in the presence of

Gold-catalyzed propargylic substitutions: Scope and synthetic developments

• Olivier Debleds,
• Eric Gayon,
• Emmanuel Vrancken and
• Jean-Marc Campagne

Beilstein J. Org. Chem. 2011, 7, 866–877, doi:10.3762/bjoc.7.99

• ruthenium catalysts for asymmetric propargylic substitutions were next developed using acetone, hydrides and electron rich aromatics as nucleophiles [16][17][18]. In 2003, oxo-rhenium catalysts were introduced by Toste [19][20][21]. Substitution products were obtained in high yields with alcohols

Ene–yne cross-metathesis with ruthenium carbene catalysts

• Cédric Fischmeister and
• Christian Bruneau

Beilstein J. Org. Chem. 2011, 7, 156–166, doi:10.3762/bjoc.7.22

• with ruthenium catalysts was initiated in 1997 when Mori [39] and Blechert [40] reported the first examples with ethylene and higher olefins, respectively. EYCM with ethylene The EYCM with ethylene is one of the simplest methods to generate conjugated dienes with two terminal methylene groups from

• transformations in the presence of ruthenium catalysts, which are able to perform regioselective allylic substitution by O-, N- and C-nucleophiles (Scheme 8a) [55] and elimination to provide a new access to dendralenes (Scheme 8b) [56]. Higher olefin–alkyne cross-metathesis This cross-metathesis reaction was

• The positive influence of ethylene in metathesis in the presence of ruthenium catalysts was first evidenced by Mori during the intramolecular ring closing metathesis of enynes [83]. The excess of ethylene would favor the formation of ruthenium methylidene intermediates, and thus prevent catalyst

Olefin metathesis in nano-sized systems

• Didier Astruc,
• Abdou K. Diallo,
• Sylvain Gatard,
• Liyuan Liang,
• Cátia Ornelas,
• Victor Martinez,
• Denise Méry and
• Jaime Ruiz

Beilstein J. Org. Chem. 2011, 7, 94–103, doi:10.3762/bjoc.7.13

• , in water instead of organic solvents is an obvious challenge that has been actively pursued [54][55][56][57] with water-soluble ruthenium catalysts [54], surfactants [58] and sonochemistry [59][60][61][62]. Using a low amount (0.083 mol %) of dendrimer, we have induced efficient olefin metathesis

The cross-metathesis of methyl oleate with cis-2-butene-1,4-diyl diacetate and the influence of protecting groups

• Arno Behr and
• Jessica Pérez Gomes

Beilstein J. Org. Chem. 2011, 7, 1–8, doi:10.3762/bjoc.7.1

• ) starting from renewable resources and quite inexpensive base chemicals. Results: This cross-metathesis reaction was carried out with several phosphine and N-heterocyclic carbene ruthenium catalysts. The reaction conditions were optimised for high conversions in combination with high cross-metathesis

• conversions in combination with high cross-metathesis selectivities. Additionally, several phosphine and N-heterocyclic carbene ruthenium catalysts were studied. The optimised reaction conditions were subsequently investigated in the cross-metathesis reaction of oleic acid (7) with the unprotected cis-2

• bearing N-heterocyclic carbene ligands (Table 1, entries 2 and 4–8) [29]. Up to 48% of methyl oleate (1) was converted and the yields of the cross-metathesis products 3 and 4 of ca. 28% were achievable with ruthenium catalysts [Ru]-2 and [Ru]-4 (Table 1, entries 2 and 4). Here, the self-metathesis