Cascade intramolecular Prins/Friedel–Crafts cyclization for the synthesis of 4-aryltetralin-2-ols and 5-aryltetrahydro-5H-benzo[7]annulen-7-ols

• Jie Zheng,
• Shuyu Meng and
• Quanrui Wang

Beilstein J. Org. Chem. 2021, 17, 1481–1489, doi:10.3762/bjoc.17.104

• therapeutic for psychoses, addiction, and other neuropsychiatric disorders. Although 4-substitituted tetralin-2-ols and derivatives with significant pharmaceutical activities have been identified, only a limited number of synthetic methods is documented in the literature (Scheme 1) [7][8][9]. Moreover, these

• to 2,4-disubstituted tetralin compounds and thus facilitate their biological investigations. The cascade Prins/Friedel–Crafts reaction to form multiple chemical bonds in one operation has emerged as an atom-economic and straightforward strategy for the construction of oxygen-containing heterocycles

• -promoted condensation of a homoallylic alcohol and an aldehyde to give an oxocarbenium ion, which is then reacted with an olefinic/alkynic bond generating a carbocation that undergoes a Friedel–Crafts reaction. Given the potential value of tetralin-2-ol scaffolds to drug research programs, we decided to

A comprehensive review of flow chemistry techniques tailored to the flavours and fragrances industries

• Guido Gambacorta,
• James S. Sharley and
• Ian R. Baxendale

Beilstein J. Org. Chem. 2021, 17, 1181–1312, doi:10.3762/bjoc.17.90

CF₃-substituted carbocations: underexploited intermediates with great potential in modern synthetic chemistry

• Anthony J. Fernandes,
• Armen Panossian,
• Bastien Michelet,
• Agnès Martin-Mingot,
• Frédéric R. Leroux and
• Sébastien Thibaudeau

Beilstein J. Org. Chem. 2021, 17, 343–378, doi:10.3762/bjoc.17.32

• tetralin derivatives 144a and 144b, respectively (Scheme 36). In addition, 144a could be further converted into 146 in the presence of aromatic nucleophiles (e.g., benzene or toluene). Similarly, derivatives 147a–c could also be converted into indanol derivatives 148a–c in high yields (Scheme 36) [95]. Ma

An overview on disulfide-catalyzed and -cocatalyzed photoreactions

• Yeersen Patehebieke

Beilstein J. Org. Chem. 2020, 16, 1418–1435, doi:10.3762/bjoc.16.118

• as the HAT cocatalyst, to generate the tetralin skeleton, which is widely seen in drugs and pesticide synthesis (Scheme 5) [13]. Diphenyl disulfide played an important role in the [4 + 2] cycloaddition process. Without diphenyl disulfide, only the product of the [2 + 2] cycloaddition was observed

Mechanochemical Friedel–Crafts acylations

• Mateja Đud,
• Anamarija Briš,
• Iva Jušinski,
• Davor Gracin and
• Davor Margetić

Beilstein J. Org. Chem. 2019, 15, 1313–1320, doi:10.3762/bjoc.15.130

• the reaction carried out in solution (40% vs 6% yield). The screening of substrates showed disparate reactivities, ranging from quantitative to low (Scheme 3). Most rewarding are reactions of toluene, o-xylene, naphthalene and tetralin. Interestingly, ball milling of 4-ethylanisole provided phenol 12

CF₃SO₂X (X = Na, Cl) as reagents for trifluoromethylation, trifluoromethylsulfenyl-, -sulfinyl- and -sulfonylation and chlorination. Part 2: Use of CF₃SO₂Cl

• Hélène Chachignon,
• Hélène Guyon and
• Dominique Cahard

Beilstein J. Org. Chem. 2017, 13, 2800–2818, doi:10.3762/bjoc.13.273

• radical cyclisation, to yield the tetralin derivative 12 (Scheme 12) [17]. In 2017, Liu and co-workers focused on N-alkenylurea derivatives 13, and from which they developed an asymmetric radical aminotrifluoromethylation methodology, based on a copper salt/chiral phosphoric acid dual-catalytic system [18

cis-Diastereoselective synthesis of chroman-fused tetralins as B-ring-modified analogues of brazilin

• Dimpee Gogoi,
• Runjun Devi,
• Pallab Pahari,
• Bipul Sarma and
• Sajal Kumar Das

Beilstein J. Org. Chem. 2016, 12, 2816–2822, doi:10.3762/bjoc.12.280

• been reductively removed by a diastereoselective method which should be useful in future for preparing libraries of chroman-fused tetralins with trans-stereochemistry at the ring junction. Keywords: brazilin; chroman; epoxy-arene cyclization; natural-product-like molecules; tetralin; Findings The

• as the key step is part of our long term objective of synthesizing chroman-based NPs and NPLMs and their subsequent application in medicinal chemistry. Like chroman, the tetralin unit has been recognized as privileged structure. We were interested to synthesize cis-6a,7,8,12b-tetrahydro-6H-naphtho

• [2,1-c]chromen-6a-ols 5 (Figure 1) as B-ring-modified analogues of brazilin through the fusion of chroman and tetralin motifs to generate new bioactive molecules. To the best of our knowledge, the stereoselective synthesis of such chroman-fused tetralins has never been reported. Based on the continuous

Stereoselective synthesis of tricyclic compounds by intramolecular palladium-catalyzed addition of aryl iodides to carbonyl groups

• Jakub Saadi,
• Christoph Bentz,
• Kai Redies,
• Dieter Lentz,
• Reinhold Zimmer and
• Hans-Ulrich Reissig

Beilstein J. Org. Chem. 2016, 12, 1236–1242, doi:10.3762/bjoc.12.118

• ketones 3–6 that led to tricyclic compounds. Methyl ketone 1 provided under the reaction conditions (2 mol % Pd(PPh3)4, 3.5 equivalents NEt3, DMF, 110 °C, 3 d) that had been optimized with compound 4 a moderate yield of the tetralin derivative 7 formed as a single diastereomer (Scheme 3). Although the

• tetralin derivatives are in the crude product mixture, but we isolated only compound 16 in pure form in 24% yield. Not surprisingly, the p-methoxy substituent favored the elimination of water from the primary addition product to generate the central double bond of 16. Discussion The nucleophilic addition

• serendipitous discovery of the palladium-catalyzed cyclization to products C. Synthesis of compounds A (1–6) via methyl 2-siloxycyclopropanecarboxylates D, their alkylation to E and fluoride-induced ring opening. Palladium-catalyzed reactions of methyl ketone 1 to tetralin derivative 7 and of isopropyl

Mechanistic studies on the CAN-mediated intramolecular cyclization of δ-aryl-β-dicarbonyl compounds

• Brian M. Casey,
• Dhandapani V. Sadasivam and
• Robert A. Flowers II

Beilstein J. Org. Chem. 2013, 9, 1472–1479, doi:10.3762/bjoc.9.167

• several natural products and biologically relevant molecules [1][2][3][4][5][6][7]. They are typically synthesized through transition-metal-mediated processes or preformed tetralin or naphthyl precursors [8][9]. Radical approaches can also be used to synthesize substituted 2-tetralones, and single

Functionalization of anthracene: A selective route to brominated 1,4-anthraquinones

• Kiymet Berkil Akar,
• Osman Cakmak,
• Orhan Büyükgüngör and
• Ertan Sahin

Beilstein J. Org. Chem. 2011, 7, 1036–1045, doi:10.3762/bjoc.7.118

• structure of tetralin oxide 26 produced from the corresponding halohydrine 25, shows the existence of hydrogen bonding between the hydroxy and the epoxy group, which has the same stereochemistry as that of compound 5 [1][14][15]. Thus, the fact that compound 23 was not obtained from 17 can be attributed to

Oxalyl retro-peptide gelators. Synthesis, gelation properties and stereochemical effects

• Janja Makarević,
• Milan Jokić,
• Leo Frkanec,
• Vesna Čaplar,
• Nataša Šijaković Vujičić and
• Mladen Žinić

Beilstein J. Org. Chem. 2010, 6, 945–959, doi:10.3762/bjoc.6.106

• aromatic acid containing gelators 3a and 5a. However, 3a and 5a also gelled small to moderate volumes of EtOH and rac-2-octanol, whilst Leu incorporating 1a formed gels with the more lipophilic solvents, decalin and tetralin. The retro-dipeptides containing two different amino acids showed no or only weak

Diastereoselective and enantioselective reduction of tetralin- 1,4-dione

• E. Peter Kündig and
• Alvaro Enriquez-Garcia

Beilstein J. Org. Chem. 2008, 4, No. 37, doi:10.3762/bjoc.4.37

• E. Peter Kundig Alvaro Enriquez-Garcia Department of Organic Chemistry, University of Geneva, 1211 Geneva 4, Switzerland 10.3762/bjoc.4.37 Abstract Background The chemistry of tetralin-1,4-dione, the stable tautomer of 1,4-dihydroxynaphthalene, has not been explored previously. It is readily

• (81%, 95% ee). Conclusion Diastereoselective and enantioselective reductions of the unexplored tetralin-1,4-dione provides a very convenient entry into a number of synthetically highly attractive 1,4-tetralindiols and 4-hydroxy-1-tetralone. Keywords: asymmetric; catalysis; ketone; reduction; tautomer

• ; Introduction In this article, we briefly review synthetic approaches to 2,3-dihydro-1,4-naphthoquinone, more simply named tetralin-1,4-dione (2). This symmetric diketone is the stable tautomer of 1,4-dihydroxynaphthalene (1). Although known for many years, it has never been used in synthesis. The reactions of