Natural phenolic metabolites with anti-angiogenic properties – a review from the chemical point of view

• Qiu Sun,
• Jörg Heilmann and
• Burkhard König

Beilstein J. Org. Chem. 2015, 11, 249–264, doi:10.3762/bjoc.11.28

•  7). Compounds 30–34 were obtained through Friedel–Crafts acylation of 29 with corresponding acyl chlorides in 55–81% yield. Subsequent alkylation with geranyl bromide gave products 35–39 in moderate yields from 55 to 60%. Finally, p-toluenesulfonic acid (pTSA)-catalyzed cyclization afforded the

• target compounds 40 and 41 in 53 and 65% yield, respectively. The synthesis of the second series is shown in Scheme 8 [59]. Amberlyst 15 efficiently catalyzed the condensation of 1,3,5-trihydroxybenzene (29) with isoprene in 53% yield. The following Friedel–Crafts acylation gave the intermediates 43–46

• inhibited angiogenic processes in various in vitro and in vivo models [82][83]. The typical synthesis of genistein starts from 1,3,5-trihydroxybenzene (29, Scheme 10) [84]. After the Houben–Hoesch reaction or Friedel–Crafts acylation, the cyclization of the resulting hydroxyketone 59 in the presence of BF3

Gold(I)-catalysed synthesis of a furan analogue of thiamine pyrophosphate

• Amjid Iqbal,
• El-Habib Sahraoui and
• Finian J. Leeper

Beilstein J. Org. Chem. 2014, 10, 2580–2585, doi:10.3762/bjoc.10.270

• synthesis of a furan-based analogue of thiamine. This analogue was converted to its diphosphate, which is another extremely potent inhibitor of ZmPDC, and could also be functionalised at the 2-position using a Friedel–Crafts acylation. Results and Discussion Synthesis of ThDP analogue 17 The key step in our

Superoxide chemistry revisited: synthesis of tetrachloro-substituted methylenenortricyclenes

• Basavaraj M. Budanur and
• Faiz Ahmed Khan

Beilstein J. Org. Chem. 2014, 10, 2531–2538, doi:10.3762/bjoc.10.264

• -di-tert-butyl-4-methylphenol) improved the yields of methylenenortricyclenes. A complete deuterium incorporation was observed in the superoxide-mediated reaction in DMSO-d6. Friedel–Crafts acylation reactions of 3-methylenenorticyclenes yielded 2-propanone-substituted pentachloronorbornenes

• . Keywords: BHT; dehydrohalogenation/rearrangement; Friedel–Crafts acylation; methylenenortricyclene; superoxide ion; Introduction The chemistry of the superoxide ion (O2−·) has been a subject of growing interest because of its presence in all aerobic organisms as a respiratory intermediate [1][2][3][4][5

Scalable synthesis of 5,11-diethynylated indeno[1,2-b]fluorene-6,12-diones and exploration of their solid state packing

• Bradley D. Rose,
• Peter J. Santa Maria,
• Aaron G. Fix,
• Chris L. Vonnegut,
• Lev N. Zakharov,
• Sean R. Parkin and
• Michael M. Haley

Beilstein J. Org. Chem. 2014, 10, 2122–2130, doi:10.3762/bjoc.10.219

• Kitamura gave tetrahalide 12 in good yield on >10 g scale [25]. Suzuki cross-coupling with 12 furnished p-terphenyl 14, followed by oxidation of the methyl groups to produce diacid 15. Intramolecular Friedel–Crafts acylation then afforded 5,11-dibromo-IF-dione 11. The yields for the Sonogashira cross

Photorelease of phosphates: Mild methods for protecting phosphate derivatives

• Sanjeewa N. Senadheera,
• Abraham L. Yousef and
• Richard S. Givens

Beilstein J. Org. Chem. 2014, 10, 2038–2054, doi:10.3762/bjoc.10.212

• with Friedel–Crafts acylation of 1-methoxynaphthalene (11) yielding 1-acetyl-4-methoxynaphthalene (12, 73%). α-Bromination with copper(II) bromide gave 13 (44%) which was converted to the phosphate ester using tetramethylammonium diethyl phosphate in dimethoxyethane (DME) at room temperature to give

Aza-Diels–Alder reaction between N-aryl-1-oxo-1H-isoindolium ions and tert-enamides: Steric effects on reaction outcome

• Amitabh Jha,
• Ting-Yi Chou,
• Zainab ALJaroudi,
• Bobby D. Ellis and
• T. Stanley Cameron

Beilstein J. Org. Chem. 2014, 10, 848–857, doi:10.3762/bjoc.10.81

• N-aryl-3-hydroxyisoindolinones with diethyl malonate and subsequent hydrolysis, decarboxylation and Friedel–Crafts acylation sequence also result in the formation of isoindolo[2,1-a]quinolones [16][17]. N-aryl-3-hydroxyisoindolinones with an aptly positioned alkene moiety at the ortho position of

Self-assembly of metallosupramolecular rhombi from chiral concave 9,9’-spirobifluorene-derived bis(pyridine) ligands

• Rainer Hovorka,
• Sophie Hytteballe,
• Torsten Piehler,
• Georg Meyer-Eppler,
• Filip Topić,
• Kari Rissanen,
• Marianne Engeser and
• Arne Lützen

Beilstein J. Org. Chem. 2014, 10, 432–441, doi:10.3762/bjoc.10.40

• subjected to an acid-mediated condensation to give the 9,9’-spirobifluorene. Friedel–Crafts acylation with acetyl chloride gave rise to the racemic 2,2’-diketone which was transformed to the racemic diester in a Baeyer–Villiger oxidation. Saponification of the ester functions then afforded (rac)-1. One part

Carbenoid-mediated nucleophilic “hydrolysis” of 2-(dichloromethylidene)-1,1,3,3-tetramethylindane with DMSO participation, affording access to one-sidedly overcrowded ketone and bromoalkene descendants^§

• Rudolf Knorr,
• Thomas Menke,
• Johannes Freudenreich and
• Claudio Pires

Beilstein J. Org. Chem. 2014, 10, 307–315, doi:10.3762/bjoc.10.28

• Friedel–Crafts acylation of arenes by the acid chloride of 10. This possibility was repudiated, however, because the similar acyl chloride t-Bu2CH–CO–Cl did not acylate benzene [37][38]. Instead, the technique [39] of acylating an aryllithium compound such as 34 by a lithium carboxylate such as 36 to form

Recent applications of the divinylcyclopropane–cycloheptadiene rearrangement in organic synthesis

• Sebastian Krüger and
• Tanja Gaich

Beilstein J. Org. Chem. 2014, 10, 163–193, doi:10.3762/bjoc.10.14

• formal [4 + 3] cycloaddition [82]. Starting from 4-methoxyphenol (90) Friedel–Crafts acylation and cyclization provided bicycle 91. Wittig olefination furnished benzofuran 92. Diazotransfer using p-ABSA yielded the crucial diazo compound 93, which was used in the following enantioselective

An overview of the synthetic routes to the best selling drugs containing 6-membered heterocycles

• Marcus Baumann and
• Ian R. Baxendale

Beilstein J. Org. Chem. 2013, 9, 2265–2319, doi:10.3762/bjoc.9.265

• moderate yield the benzoxazine 1.118; via the imine intermediate. This material can then be condensed with diethyl ethoxymethylenemalonate (1.123), and further cyclised via an intramolecular Friedel–Crafts acylation promoted by polyphosphate. Aluminium tribromide assisted demethylation of the pendant

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

• oxalyl chloride and the Lewis acid tin(IV) chloride, a tandem cyclization (Bischler–Napieralski/Friedel–Crafts acylation reaction) was triggered to directly give 137 and 149 [122][127]. In 2006, another approach to aristoyagonine (136) was reported by the group of Couture (Scheme 20) [128]. For the

Polymerization of novel methacrylated anthraquinone dyes

• Christian Dollendorf,
• Susanne Katharina Kreth,
• Soo Whan Choi and
• Helmut Ritter

Beilstein J. Org. Chem. 2013, 9, 453–459, doi:10.3762/bjoc.9.48

• –Crafts acylation followed by an acidic ring closure (Scheme 1, step b). In further reaction steps, 1,4-dichloroanthraquinone (3) and hydroxyaniline were reacted to obtain 1,4-bis(4-hydroxyphenylamino)anthraquinone (4). Subsequent reaction with 2-bromoethanol gave 1,4-bis(4-((2-hydroxyethyl)oxy

• absorption in two different areas of the visible spectrum. Polymerizable blue dye 6 based on anthraquinone For the synthesis of the blue anthraquinone based monomeric dye 6, the precursor 1,4-dichloroanthraquinone (3) was prepared by the reaction of 1,4-dichlorobenzene with phthalic dichloride by Friedel

An efficient access to the synthesis of novel 12-phenylbenzo[6,7]oxepino[3,4-b]quinolin-13(6H)-one derivatives

• Wentao Gao,
• Guihai Lin,
• Yang Li,
• Xiyue Tao,
• Rui Liu and
• Lianjie Sun

Beilstein J. Org. Chem. 2012, 8, 1849–1857, doi:10.3762/bjoc.8.213

• , is described, involving the intramolecular Friedel–Crafts acylation reaction of 2-(phenoxymethyl)-4-phenylquinoline-3-carboxylic acid derivatives 3a–l aided by the treatment with PPA (polyphosphoric acid) or Eaton’s reagent. The required starting compound (2) was obtained by Friedländer reaction of 2

• three-step route, offers easy access to tetracyclic-fused quinoline systems in short reaction times, and the products are obtained in moderate to good yields. Keywords: Eaton’s reagent; Friedel–Crafts acylation; Friedländer reaction; one-pot; PPA; quinoline; tetracyclic-fused; Introduction Polycyclic

• nature of the bulky tert-butyl group at the o-position of aryl. Thus, the resulting substrates, quinoline-3-carboxylic acids 3a–l, further served as active synthons for the intramolecular Friedel–Crafts acylation reaction to construct the desired tetracyclic benzoxepino-fused quinoline systems. Of the

Fifty years of oxacalix[3]arenes: A review

• Kevin Cottet,
• Paula M. Marcos and
• Peter J. Cragg

Beilstein J. Org. Chem. 2012, 8, 201–226, doi:10.3762/bjoc.8.22

• -substituted phenol; however, in host–guest chemistry an asymmetric macrocycle can provide a site for enantioselective molecular recognition. In the case of p-tert-butylcalix[n]arenes the tert-butyl substituent can be removed, as mentioned previously, through a retro-Friedel–Crafts acylation, and replaced by

An overview of the key routes to the best selling 5-membered ring heterocyclic pharmaceuticals

• Marcus Baumann,
• Ian R. Baxendale,
• Steven V. Ley and
• Nikzad Nikbin

Beilstein J. Org. Chem. 2011, 7, 442–495, doi:10.3762/bjoc.7.57

New diarylmethanofullerene derivatives and their properties for organic thin- film solar cells

• Daisuke Sukeguchi,
• Surya Prakash Singh,
• Mamidi Ramesh Reddy,
• Hideyuki Yoshiyama,
• Rakesh A. Afre,
• Yasuhiko Hayashi,
• Hiroki Inukai,
• Tetsuo Soga,
• Shuichi Nakamura,
• Norio Shibata and
• Takeshi Toru

Beilstein J. Org. Chem. 2009, 5, No. 7, doi:10.3762/bjoc.5.7

• heterojunction thin film. Synthesis of diarylmethanofullerene derivatives Diarylmethanofullerene derivatives were synthesized according to the method cited in the literature [26]. Synthetic routes are shown in Scheme 1. Generally, the Friedel–Crafts acylation of benzene derivatives 10–14 with acid chlorides 3–9

Transition- metal/Lewis acid free synthesis of acyl benzothiophenes via C-C bond forming reaction

• Sarbani Pal,
• Mohammad Ashrafuddin Khan,
• P. Bindu and
• P. K. Dubey

Beilstein J. Org. Chem. 2007, 3, No. 35, doi:10.1186/1860-5397-3-35

• acylation has been reported as a useful alternative to the Friedel-Crafts acylation process and a variety of aromatic and aliphatic carboxylic acids have been employed successfully. Encouraged by these results, we decided to adopt a similar strategy for the acylation of benzothiophene. We anticipated that a

• . Nevertheless, the present process is certainly superior to the classical Friedel-Crafts acylation technique and other multi step synthesis. Further studies on establishing the regeioselectivity and application of this methodology in organic synthesis are under investigation. Acyl benzothiophenes of

• Crafts acylation reaction [21][22][23][24] which however, involved the use of excess AlCl3 and led to the formation of environmentally harmful gaseous HCl. Moreover, this protocol involved i) the use of moisture-sensitive acyl chloride, ii) the use of a large volume of chlorinated solvent and iii) the