The first example of the Fischer–Hepp type rearrangement in pyrimidines

• Inga Cikotiene,
• Mantas Jonusis and
• Virginija Jakubkiene

Beilstein J. Org. Chem. 2013, 9, 1819–1825, doi:10.3762/bjoc.9.212

• -defficient character of this heterocycle. An electrophilic aromatic substitution at the C-5 of a pyrimidine is usually difficult [1][3][4][5]. However, the presence of two or three activating groups leads to the successful introduction of an electrophile (Scheme 1) [1][6][7][8]. On the other hand

Utilizing the σ-complex stability for quantifying reactivity in nucleophilic substitution of aromatic fluorides

• Magnus Liljenberg,
• Tore Brinck,
• Tobias Rein and
• Mats Svensson

Beilstein J. Org. Chem. 2013, 9, 791–799, doi:10.3762/bjoc.9.90

• and industrially important SNAr and SEAr reactions (nucleophilic and electrophilic aromatic substitution, respectively) [3][4][5]. The putative mechanism for the SNAr reaction involves attack of a nucleophile and the formation of an intermediate σ-complex (also called the Meisenheimer complex

Facile synthesis of functionalized tetrahydroquinolines via domino Povarov reactions of arylamines, methyl propiolate and aromatic aldehydes

• Jing Sun,
• Hong Gao,
• Qun Wu and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2012, 8, 1839–1843, doi:10.3762/bjoc.8.211

• addition of intermediate A with the acid-promoted N-aryl aldimine B gives the intermediate C. Lastly, the intramolecular electrophilic aromatic substitution at the ortho position of the activated N-aryl ring gives the final tetrahydroquinoline 1. On the other hand, the concerted imine-Diels–Alder reaction

Highly selective synthesis of (E)-alkenyl-(pentafluorosulfanyl)benzenes through Horner–Wadsworth–Emmons reaction

• George Iakobson and
• Petr Beier

Beilstein J. Org. Chem. 2012, 8, 1185–1190, doi:10.3762/bjoc.8.131

• cyclized product 10d resulting from electrophilic aromatic substitution of the substituted phenyl cation intermediate (formed by the decomposition of the diazonium salt), to the electron-rich anisole ring in an unusual meta-position relative to the methoxy group. The more activated para-position is

• 11d in good yield (Scheme 4). To avoid problems with alkene reduction and electrophilic aromatic substitution during nitro group removal, we decided to try a different approach to the general synthesis of SF5-containing stilbene derivatives, as demonstrated in the synthesis of 13d shown in Scheme 5

One-pot four-component synthesis of pyrimidyl and pyrazolyl substituted azulenes by glyoxylation–decarbonylative alkynylation–cyclocondensation sequences

• Charlotte F. Gers,
• Julia Rosellen,
• Eugen Merkul and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2011, 7, 1173–1181, doi:10.3762/bjoc.7.136

• elucidation of the structure and the first synthesis of the azulene skeleton by Pfau and Plattner [21][22], its reactivity has been intensively studied [23][24][25][26]. The aromatic system is susceptible to nucleophilic addition in the 4-, 6- and 8-positions [23], whereas electrophilic aromatic substitution

One-pot gold-catalyzed synthesis of 3-silylethynyl indoles from unprotected o-alkynylanilines

• Jonathan P. Brand,
• Clara Chevalley and
• Jérôme Waser

Beilstein J. Org. Chem. 2011, 7, 565–569, doi:10.3762/bjoc.7.65

• functionalization have been extensively studied [3][4]. Among the numerous syntheses of indoles, the cyclization of 2-alkynylanilines has the advantage that the resulting products, 2-substituted indoles, are easily functionalized by electrophilic aromatic substitution at position 3. Traditionally, this

Anion–π interactions influence pK_a values

• Christopher J. Cadman and
• Anna K. Croft

Beilstein J. Org. Chem. 2011, 7, 320–328, doi:10.3762/bjoc.7.42

• aromatic substitution. The pKa' values for these 1,8-disubstituted arene naphthols have been measured in acetonitrile/water (R = NO2, 8.42; R = Cl, 8.52; R = H, 8.56; R = Me 8.68; and R = OMe, 8.71) and indicate a correlation with the electronic nature of the arene substituent, as determined through LFER

• Christopher J. Cadman Anna K. Croft School of Chemistry, University of Wales Bangor, Bangor, Gwynedd, LL57 2UW, United Kingdom. Fax: +44 1248 370 528. Tel: +44 1248 382 375 10.3762/bjoc.7.42 Abstract Five 8-(4-R-phenyl)-1-naphthol derivatives were prepared by PdCl2-catalysed electrophilic

SbCl₃-catalyzed one-pot synthesis of 4,4′-diaminotriarylmethanes under solvent-free conditions: Synthesis, characterization, and DFT studies

• Ghasem Rezanejade Bardajee

Beilstein J. Org. Chem. 2011, 7, 135–144, doi:10.3762/bjoc.7.19

• the reaction can be summarized as a tandem regioselective electrophilic aromatic substitution reaction of N,N-dimethylaniline and aldehydes, in which SbCl3 (as a Lewis acid catalyst) activates the carbonyl group of the aldehydes. If we accept this mechanism, one can expect a general influence of

Trifluoromethyl ethers – synthesis and properties of an unusual substituent

• Frédéric R. Leroux,
• Baptiste Manteau,
• Jean-Pierre Vors and
• Sergiy Pazenok

Beilstein J. Org. Chem. 2008, 4, No. 13, doi:10.3762/bjoc.4.13

• electron withdrawing behavior to the alkoxy group but also acts to deactivate the aromatic ring system [53]. Electrophilic Aromatic Substitution Trifluoromethoxybenzene, for example, undergoes nitration considerably (up to 5 times) more slowly than benzene. The electrophilic substitution occurs selectively