Copper-catalyzed aminooxygenation of styrenes with N-fluorobenzenesulfonimide and N-hydroxyphthalimide derivatives

• Yan Li,
• Xue Zhou,
• Guangfan Zheng and
• Qian Zhang

Beilstein J. Org. Chem. 2015, 11, 2721–2726, doi:10.3762/bjoc.11.293

• aminooxygenation reaction of alkenes with phthalimide and (diacetoxyiodo)benzene through cis-aminopalladation and SN2 C–O bond formation [34]. In 2013, Zhu and co-workers described an n-Bu4NI-catalyzed aminooxygenation of inactive alkenes with benzotriazole and water which underwent a nitrogen-centred radical

Iron complexes of tetramine ligands catalyse allylic hydroxyamination via a nitroso–ene mechanism

• David Porter,
• Belinda M.-L. Poon and
• Peter J. Rutledge

Beilstein J. Org. Chem. 2015, 11, 2549–2556, doi:10.3762/bjoc.11.275

• ) are established catalysts of C–O bond formation, oxidising hydrocarbon substrates via hydroxylation, epoxidation and dihydroxylation pathways. Herein we report the capacity of these catalysts to promote C–N bond formation, via allylic amination of alkenes. The combination of N-Boc-hydroxylamine with

Copper-catalyzed aerobic radical C–C bond cleavage of N–H ketimines

• Ya Lin Tnay,
• Gim Yean Ang and
• Shunsuke Chiba

Beilstein J. Org. Chem. 2015, 11, 1933–1943, doi:10.3762/bjoc.11.209

• spirocyclization of the alkoxy radical D onto the benzene ring affords cyclohexadienyl radical F, oxygenation of which followed by C=O bond formation finally provides the oxaspirocyclohexadienone product 3a. Whereas, the oxidation of the benzylic radical B by the existing Cu(II) species to carbocation G and

Cross-dehydrogenative coupling for the intermolecular C–O bond formation

• Igor B. Krylov,
• Vera A. Vil’ and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2015, 11, 92–146, doi:10.3762/bjoc.11.13

• reactions of CH- and OH-reagents, closely related C–H activation processes involving intermolecular C–O bond formation are discussed: acyloxylation reactions with ArI(O2CR)2 reagents and generation of O-reagents in situ from C-reagents (methylarenes, aldehydes, etc.). Keywords: acyloxylation; alkoxylation

• ; C–H functionalization; C–O bond formation; cross-dehydrogenative coupling; oxidative cross-coupling; Introduction The development of methods for the cross-dehydrogenative coupling (CDC; or oxidative cross coupling) is an important field of modern organic chemistry. These terms commonly refer to

• these radicals are often non-selective and are accompanied by the formation of alcohols, carbonyl compounds, and fragmentation products. The examples of the C–O bond formation between two molecules using O-electrophiles are rare; electron-deficient peroxides with a specific structure can act as O

Synthesis of ethoxy dibenzooxaphosphorin oxides through palladium-catalyzed C(sp²)–H activation/C–O formation

• Seohyun Shin,
• Dongjin Kang,
• Woo Hyung Jeon and
• Phil Ho Lee

Beilstein J. Org. Chem. 2014, 10, 1220–1227, doi:10.3762/bjoc.10.120

• We report an efficient Pd-catalyzed C(sp2)–H activation/C–O bond formation for the synthesis of ethoxy dibenzooxaphosphorin oxides from 2-(aryl)arylphosphonic acid monoethyl esters under aerobic conditions. Keywords: C–H activation; catalysis; cyclization; palladium; phosphorus heterocyclic compound

Copper-catalyzed aerobic aliphatic C–H oxygenation with hydroperoxides

• Pei Chui Too,
• Ya Lin Tnay and
• Shunsuke Chiba

Beilstein J. Org. Chem. 2013, 9, 1217–1225, doi:10.3762/bjoc.9.138

• generate the corresponding C-radicals (Scheme 1a) [7]. The successive trapping of the resulting C-radicals with molecular O2 forms peroxy radicals (the C–O bond formation). Reduction of peroxy radicals generates alkoxides, cyclization of which with the amidine moiety finally affords dihydrooxazoles

Tandem dinucleophilic cyclization of cyclohexane-1,3-diones with pyridinium salts

• Mostafa Kiamehr,
• Firouz Matloubi Moghaddam,
• Satenik Mkrtchyan,
• Volodymyr Semeniuchenko,
• Linda Supe,
• Alexander Villinger,
• Peter Langer and
• Viktor O. Iaroshenko

Beilstein J. Org. Chem. 2013, 9, 1119–1126, doi:10.3762/bjoc.9.124

• -diketone deprotonation and nucleophilic attack of potassium 3-oxocyclohex-1-enolate on pyridinium cation, which yields an intermediate with a new C–C bond, and this is a key stage in the reaction. The C–O bond formation can be excluded in the initial stage (see Supporting Information File 2 for the

Complete σ* intramolecular aromatic hydroxylation mechanism through O₂ activation by a Schiff base macrocyclic dicopper(I) complex

• Albert Poater and
• Miquel Solà

Beilstein J. Org. Chem. 2013, 9, 585–593, doi:10.3762/bjoc.9.63

• and C–O bond formation, followed finally by a proton transfer to an alpha aromatic carbon that immediately yields the product [CuII2(bsH2m-O)(μ-OH)]2+. Keywords: aromatic hydroxylation; C–H bond activation; C–H functionalization; copper; DFT calculations; mechanism; Schiff base; Introduction Bearing

• isomeric species was not located, probably due the higher rigidity that is imposed by the Schiff bases bsH2m with respect to the similar, previously described system H3m [40]. The two possible routes from d to e (C–O bond formation) corresponding to the attacks on the two phenyl rings are basically

Palladium-catalyzed C–N and C–O bond formation of N-substituted 4-bromo-7-azaindoles with amides, amines, amino acid esters and phenols

• Rajendra Surasani,
• Dipak Kalita,
• A. V. Dhanunjaya Rao and
• K. B. Chandrasekhar

Beilstein J. Org. Chem. 2012, 8, 2004–2018, doi:10.3762/bjoc.8.227

• .8.227 Abstract Simple and efficient procedures for palladium-catalyzed cross-coupling reactions of N-substituted 4-bromo-7-azaindole (1H-pyrrole[2,3-b]pyridine), with amides, amines, amino acid esters and phenols through C–N and C–O bond formation have been developed. The C–N cross-coupling reaction of

• amines, alcohols and phenols [5][7][31][32][33][34][35][36], very few studies on the formation of C–N and C–O bond formation over 7-azaindole have been performed [37][38][39]. On the other hand, the chemistry of 4-bromo-7-azaindole has not been explored in depth until today. Amino and phenyl-substituted

• and amino acid esters, we wanted to expand the scope of the reaction towards C–O-bond formation. Until today no general method has been described for the C–O-bond-formation reaction of 4-halo-azaindole with phenols or alcohols. Most of the literature reports described on C–O-bond-formation reactions

Screening of ligands for the Ullmann synthesis of electron-rich diaryl ethers

• Nicola Otto and
• Till Opatz

Beilstein J. Org. Chem. 2012, 8, 1105–1111, doi:10.3762/bjoc.8.122

• limitations due to the use of stoichiometric or superstoichiometric amounts of copper powder and typically requires high reaction temperatures (≈200 °C), thus tolerating only a limited number of functional groups. Alternatively, C–O bond formation can be accomplished by efficient Pd-catalyzed arylations of

• temperatures, 56 structurally diverse multidentate ligands were screened in a model system that uses copper iodide in acetonitrile with potassium phosphate as the base. The ligands differed largely in their performance, but no privileged structural class could be identified. Keywords: catalysis; C–O bond

• formation; diaryl ethers; nucleophilic aromatic substitution; Ullmann-type coupling; Introduction The diaryl ether linkage is a common structural motif encountered in numerous classes of natural products. Moreover, various diaryl ethers have been shown to possess antibacterial, anti-inflammatory

Recent advances in the gold-catalyzed additions to C–C multiple bonds

• He Huang,
• Yu Zhou and
• Hong Liu

Beilstein J. Org. Chem. 2011, 7, 897–936, doi:10.3762/bjoc.7.103

• enriched secondary propargyl alcohols led to the chiral oxetan-3-one with no apparent racemization (Scheme 20). 3 Gold-catalyzed C–N bond formations Many organic compounds containing nitrogen exhibit important biological and pharmaceutical properties. As with gold-catalyzed C–O bond formation, the directly

C–C (alkynylation) vs C–O (ether) bond formation under Pd/C–Cu catalysis: synthesis and pharmacological evaluation of 4-alkynylthieno[2,3-d]pyrimidines

• Dhilli Rao Gorja,
• K. Shiva Kumar,
• K. Mukkanti and
• Manojit Pal

Beilstein J. Org. Chem. 2011, 7, 338–345, doi:10.3762/bjoc.7.44

• /C–CuI–PPh3 catalytic system facilitated C–C bond formation between 4-chlorothieno[2,3-d]pyrimidines and terminal alkynes in methanol with high selectivity without generating any significant side products arising from C–O bond formation between the chloro compounds and methanol. A variety of novel 4

• the expected product via a C–C bond forming reaction (Scheme 3, path a) and no side product as a result of C–O bond formation [11] due to participation of MeOH (Scheme 3, path b) was detected in the reaction mixture. The use of MeOH as a nucleophile in Pd-catalyzed reactions has been well documented

• and hydrophilic terminal alkynes without generating any significant side products arising from C–O bond formation or dimerization of the terminal alkynes. The reaction does not involve the use of expensive catalysts or reagents and is easy to perform. Some of the compounds synthesized were tested for

Pd/C-mediated synthesis of α-pyrone fused with a five-membered nitrogen heteroaryl ring: A new route to pyrano[4,3-c]pyrazol-4(1H)-ones

• Dhilli Rao Gorja,
• Venkateswara Rao Batchu,
• Ashok Ettam and
• Manojit Pal

Beilstein J. Org. Chem. 2009, 5, No. 64, doi:10.3762/bjoc.5.64

• pyrano[4,3-c]pyrazol-4(1H)-ones under Pd/C-Cu catalysis, preparation of which would be difficult via other methods. The reaction proceeds via tandem C-C and C-O bond formation between the 5-iodopyrazole-4-carboxylic acid and a terminal alkyne in the same pot. Being an integral part of many drugs or