First synthesis of acylated nitrocyclopropanes

• Kento Iwai,
• Rikiya Kamidate,
• Khimiya Wada,
• Haruyasu Asahara and
• Nagatoshi Nishiwaki

Beilstein J. Org. Chem. 2023, 19, 892–900, doi:10.3762/bjoc.19.67

• , but a dihydrofuran, so the cyclopropane 1b’ reported in the literature [12][13][19] is presumably incorrect [22]. In the cases of donor–acceptor cyclopropanes possessing an electron-donating group such as an alkoxy or amino group, ring expansion caused by an intramolecular attack of nitro oxygen

Nucleophile-induced ring contraction in pyrrolo[2,1-c][1,4]benzothiazines: access to pyrrolo[2,1-b][1,3]benzothiazoles

• Ekaterina A. Lystsova,
• Maksim V. Dmitriev,
• Andrey N. Maslivets and
• Ekaterina E. Khramtsova

Beilstein J. Org. Chem. 2023, 19, 646–657, doi:10.3762/bjoc.19.46

• -aminothiophenol with donor–acceptor cyclopropanes (Scheme 2, entry 10) [27], condensations of o-aminothiophenol with 4-oxo acids or their derivatives (Scheme 2, entry 11) [2][28][29][30][31] and cascade reactions of o-aminothiophenol, furfural and anhydrides of 2,3-unsaturated carboxylic acids (Scheme 2, entry 12

Reductive opening of a cyclopropane ring in the Ni(II) coordination environment: a route to functionalized dehydroalanine and cysteine derivatives

• Oleg A. Levitskiy,
• Olga I. Aglamazova,
• Yuri K. Grishin and
• Tatiana V. Magdesieva

Beilstein J. Org. Chem. 2022, 18, 1166–1176, doi:10.3762/bjoc.18.121

• ][26]. Donor–acceptor cyclopropanes constitute an easily available equivalent of all-carbon 1,3-zwitter-ions used in targeted synthesis of various alicyclic as well as carbo- or heterocyclic compounds [27][28][29][30]. The reactive synergy of the three-membered ring and the C–C bond polarization due to

• recently, two publications from the Werz group appeared concerning anodic activation of donor–acceptor cyclopropanes followed by their functionalization with arenes [43] or yielding oxy-ketones or 1,2-dioxanes [44]; the latter process was inspired by a previous report of Buriez [45]. The anodic

Regioselectivity of the S_EAr-based cyclizations and S_EAr-terminated annulations of 3,5-unsubstituted, 4-substituted indoles

• Jonali Das and
• Sajal Kumar Das

Beilstein J. Org. Chem. 2022, 18, 293–302, doi:10.3762/bjoc.18.33

• V. Electrocyclization of V followed by loss of proton from the intermediate VI afforded the corresponding cyclopenta[e]indol-6-ones 35a,b. While involved in the synthesis of 9H-fluorenes and 9,10-dihydrophenanthrenes through intramolecular arylative ring-opening of indole-tethered donor–acceptor

• cyclopropanes, Li and co-workers treated compound 36 with triflic acid (TfOH) in refluxing HFIP (Scheme 13) [24]. The reaction afforded compound 37 in 82% through the regioselective intramolecular ring-opening of the cyclopropane ring at the benzylic carbon atom. Very recently, our group has reported the

Selective and reversible 1,3-dipolar cycloaddition of 6-aryl-1,5-diazabicyclo[3.1.0]hexanes with 1,3-diphenylprop-2-en-1-ones under microwave irradiation

• Alexander P. Molchanov,
• Mariia M. Efremova,
• Mariya A. Kryukova and
• Mikhail A. Kuznetsov

Beilstein J. Org. Chem. 2020, 16, 2679–2686, doi:10.3762/bjoc.16.218

• that the Lewis acid-catalyzed reaction of diaziridines with donor–acceptor cyclopropanes and aziridines affords the perhydropyridazine or triazine derivatives, respectively, in good yields [31][32][33]. The use of microwave irradiation in organic synthesis complies with the principles of green

Ferrocenyl-substituted tetrahydrothiophenes via formal [3 + 2]-cycloaddition reactions of ferrocenyl thioketones with donor–acceptor cyclopropanes

• Grzegorz Mlostoń,
• Mateusz Kowalczyk,
• André U. Augustin,
• Peter G. Jones and
• Daniel B. Werz

Beilstein J. Org. Chem. 2020, 16, 1288–1295, doi:10.3762/bjoc.16.109

• thioketones reacted with donor–acceptor cyclopropanes in dichloromethane at room temperature in the presence of catalytic amounts of Sc(OTf)3 yielding tetrahydrothiophene derivatives, products of formal [3 + 2]-cycloaddition reactions, in moderate to high yields. In all studied cases, dimethyl 2

• thioketones to form nearly equal amounts of both diastereoisomeric tetrahydrothiophenes. A low selectivity was also observed in the reaction of a 2-phthalimide-derived cyclopropane with ferrocenyl phenyl thioketone. Keywords: [3 + 2]-cycloaddition reactions; donor–acceptor cyclopropanes; ferrocenyl

• thioketones (also thionoesters) with donor–acceptor cyclopropanes 5 (D–A cyclopropanes) were realized. In contrast, thiochalcones (α,β-unsaturated aromatic thioketones) were shown to react under similar conditions with cyclopropanes 5 yielding exclusively seven-membered tetrahydrothiepines 7 as products of