Direct and indirect single electron transfer (SET)-photochemical approaches for the preparation of novel phthalimide and naphthalimide-based lariat-type crown ethers

• Dae Won Cho,
• Patrick S. Mariano and
• Ung Chan Yoon

Beilstein J. Org. Chem. 2014, 10, 514–527, doi:10.3762/bjoc.10.47

• the low oxidation potentials and known reactivity profile of cation radicals arising from α-trialkylsilyl substituted n-electron donors, it is feasible to design substrates that undergo sequential SET-desilylation processes to produce radicals or biradical intermediates in a highly regioselective and

Silica: An efficient catalyst for one-pot regioselective synthesis of dithioethers

• Samir Kundu,
• Babli Roy and
• Basudeb Basu

Beilstein J. Org. Chem. 2014, 10, 26–33, doi:10.3762/bjoc.10.5

• % yield. In both cases, a minimal amount of diphenyldisulfide (5–10%) was formed [43][44], which was easily separable from the reaction mixture by column chromatography. Since the choice of silica led to the production of highly regioselective products, we wanted to optimize both conditions to establish

The chemistry of isoindole natural products

• Klaus Speck and
• Thomas Magauer

Beilstein J. Org. Chem. 2013, 9, 2048–2078, doi:10.3762/bjoc.9.243

• diene precursor 220 could be prepared in seven steps. The following Diels–Alder reaction with chloroethynylquinone 221, which was synthesized according to a known procedure [165] proceeded in a highly regioselective manner to give antharaquinone 222. Introduction of the fused hydrofuran–hydrofuranone

Gold-catalyzed regioselective oxidation of propargylic carboxylates: a reliable access to α-carboxy-α,β-unsaturated ketones/aldehydes

• Kegong Ji,
• Jonathan Nelson and
• Liming Zhang

Beilstein J. Org. Chem. 2013, 9, 1925–1930, doi:10.3762/bjoc.9.227

• scope is much limited, and the catalyst loading is 20%. With this oxidative gold catalysis, the propargyl esters, except those derived from tertiary alcohols, can be reliably converted into α-acyloxy α,β-unsaturated ketones/aldehydes. Conclusion We have realized a gold-catalyzed, highly regioselective

Regio- and stereoselective carbometallation reactions of N-alkynylamides and sulfonamides

• Yury Minko,
• Morgane Pasco,
• Helena Chechik and
• Ilan Marek

Beilstein J. Org. Chem. 2013, 9, 526–532, doi:10.3762/bjoc.9.57

• carbocupration reactions of heterosubstituted alkynes allow the regio- and stereoselective formation of vinyl organometallic species. N-Alkynylamides (ynamides) are particularly useful substrates for the highly regioselective carbocupration reaction, as they lead to the stereodefined formation of vinylcopper

Intramolecular carbolithiation of N-allyl-ynamides: an efficient entry to 1,4-dihydropyridines and pyridines – application to a formal synthesis of sarizotan

• Wafa Gati,
• Mohamed M. Rammah,
• Mohamed B. Rammah and
• Gwilherm Evano

Beilstein J. Org. Chem. 2012, 8, 2214–2222, doi:10.3762/bjoc.8.250

• 10.3762/bjoc.8.250 Abstract We have developed a general synthesis of polysubstituted 1,4-dihydropyridines and pyridines based on a highly regioselective lithiation/6-endo-dig intramolecular carbolithiation from readily available N-allyl-ynamides. This reaction, which has been successfully applied to the

Highly stereocontrolled synthesis of trans-enediynes via carbocupration of fluoroalkylated diynes

• Tsutomu Konno,
• Misato Kishi and
• Takashi Ishihara

Beilstein J. Org. Chem. 2012, 8, 2207–2213, doi:10.3762/bjoc.8.249

• ; carbometallation; diyne; enediyne; fluorine; highly regioselective; highly stereoselective; Introduction trans-Enediynes (trans-hex-3-ene-1,5-diynes), as shown in Figure 1, are well-recognized as one of the most important building blocks because they are frequently utilized for the synthesis of π-conjugated

Copper-catalyzed CuAAC/intramolecular C–H arylation sequence: Synthesis of annulated 1,2,3-triazoles

• Rajkumar Jeyachandran,
• Harish Kumar Potukuchi and
• Lutz Ackermann

Beilstein J. Org. Chem. 2012, 8, 1771–1777, doi:10.3762/bjoc.8.202

• only accomplished with more expensive palladium [55][56][57][58][59][60][61][62] or ruthenium [63][64][65][66] catalysts. Notably, this strategy allowed for the atom-economical synthesis of fully substituted 1,2,3-triazoles in a highly regioselective fashion [54][67]. While the research groups of

Regioselective synthesis of 7,8-dihydroimidazo[5,1-c][1,2,4]triazine-3,6(2H,4H)-dione derivatives: A new drug-like heterocyclic scaffold

• Nikolay T. Tzvetkov,
• Harald Euler and
• Christa E. Müller

Beilstein J. Org. Chem. 2012, 8, 1584–1593, doi:10.3762/bjoc.8.181

• dioxane under reflux [21] (Scheme 4). The products were purified chromatographically and the preferred regioselectivity (C5 versus C2) was confirmed by NMR spectroscopy. The formation of C2-thiocarbonyl by-products was not observed under these reaction conditions. The highly regioselective formation of

Biocatalytic hydroxylation of n-butane with in situ cofactor regeneration at low temperature and under normal pressure

• Svenja Staudt,
• Christina A. Müller,
• Jan Marienhagen,
• Christian Böing,
• Stefan Buchholz,
• Ulrich Schwaneberg and
• Harald Gröger

Beilstein J. Org. Chem. 2012, 8, 186–191, doi:10.3762/bjoc.8.20

• . In addition, a biocatalytic oxidation of n-butane, as a representative example for a “liquid gas”, was carried out with enzymatic in situ cofactor regeneration and without the need for high-pressure conditions, in a highly regioselective fashion. This process, running at an initial reaction

Gold-catalyzed regioselective oxidation of terminal allenes: formation of α-methanesulfonyloxy methyl ketones

• Yingdong Luo,
• Guozhu Zhang,
• Erik S. Hwang,
• Thomas A. Wilcoxon and
• Liming Zhang

Beilstein J. Org. Chem. 2011, 7, 596–600, doi:10.3762/bjoc.7.69

• , whilst the latter suffers from low regioselectivities. This gold-catalyzed approach offers an attractive alternative that is highly regioselective, catalytic on gold and takes place under relatively mild reaction conditions. The mechanism of this highly regioselective gold-catalyzed oxidation of allenes

An efficient and practical entry to 2-amido-dienes and 3-amido-trienes from allenamides through stereoselective 1,3-hydrogen shifts

• Ryuji Hayashi,
• John B. Feltenberger,
• Andrew G. Lohse,
• Mary C. Walton and
• Richard P. Hsung

Beilstein J. Org. Chem. 2011, 7, 410–420, doi:10.3762/bjoc.7.53

• -hydrogen shifts from allenamides are described. These 1,3-hydrogen shifts could be achieved thermally or they could be promoted by the use of Brønsted acids. Under either condition, these processes are highly regioselective in favour of the α-position, and highly stereoselective in favour of the E

• preparation of de novo acyclic 2-amido-dienes and 3-amido-trienes through 1,3-hydrogen shifts from allenamides. These 1,3-hydrogen shifts could be achieved under thermal conditions or they could be promoted with Brønsted acids. Under either condition, these processes are highly regioselective in favour of the

Gold film- catalysed benzannulation by Microwave- Assisted, Continuous Flow Organic Synthesis (MACOS)

• Gjergji Shore,
• Michael Tsimerman and
• Michael G. Organ

Beilstein J. Org. Chem. 2009, 5, No. 35, doi:10.3762/bjoc.5.35

• of catalysing benzannulation reactions. The cycloaddition precursors are flowed through these capillaries while the metal film is being heated to high temperatures using microwave irradiation. The transformation can be optimized rapidly, tolerates a wide number of functional groups, is highly

• regioselective, and proceeds in good to excellent conversion. Keywords: benzannulation; flow synthesis; gold catalysis; microwave; thin metal film; Introduction Microwave-assisted organic synthesis (MAOS) has had a significant impact on organic and medicinal chemistry by dramatically shortening reaction times

Recent progress on the total synthesis of acetogenins from Annonaceae

• Nianguang Li,
• Zhihao Shi,
• Yuping Tang,
• Jianwei Chen and
• Xiang Li

Beilstein J. Org. Chem. 2008, 4, No. 48, doi:10.3762/bjoc.4.48

Understanding the mechanism of Pd-catalyzed allylic substitution of the cyclic difluorinated carbonates

• Jun Xu,
• Xiao-Long Qiu and
• Feng-Ling Qing

Beilstein J. Org. Chem. 2008, 4, No. 18, doi:10.3762/bjoc.4.18

• -catalyzed reactions of cyclic gem-difluorinated allylic carbonates 1 and 4 proceeded via the symmetric Pd-π-allyl bonding and highly regioselective γ-substitution resulted from the neighboring gem-difluoromethylene group. We propose that the present work opens a new avenue for the further insight into the

Synthesis of (–)-Indolizidine 167B based on domino hydroformylation/cyclization reactions

• Giuditta Guazzelli,
• Raffaello Lazzaroni and
• Roberta Settambolo

Beilstein J. Org. Chem. 2008, 4, No. 2, doi:10.1186/1860-5397-4-2

• Chimica e Chimica Industriale, Università di Pisa, Via Risorgimento 35, 56126 Pisa, Italy 10.1186/1860-5397-4-2 Abstract The synthesis of (–)-Indolizidine 167B has been achieved from optically active (R)-3-(pyrrol-1-yl)hex-1-ene. The key step is a highly regioselective hydroformylation reaction and a one

• highly regioselective hydroformylation into the linear aldehyde takes place; this is a consequence of the isomerization of the branched alkyl-rhodium intermediate b, precursor of 2b, into the linear one l, precursor of 2a, via a ß-elimination process with formation of olefin 1 (Scheme 2) [22]. This

Synthesis and glycosidase inhibitory activity of new hexa- substituted C8-glycomimetics

• Olivia Andriuzzi,
• Christine Gravier-Pelletier,
• Gildas Bertho,
• Thierry Prangé and
• Yves Le Merrer

Beilstein J. Org. Chem. 2005, 1, No. 12, doi:10.1186/1860-5397-1-12

• afforded the corresponding azido-alcohols 11 and 12, isolated as single stereoisomers in excellent yield (95–98%). No other isomer of 11 or 12 was detected by NMR analysis, indicating that the ring-opening reaction is highly regioselective and results in the anti addition of the azido group on the opposite