Synthesis of π-conjugated polycyclic compounds by late-stage extrusion of chalcogen fragments

• Aissam Okba,
• Pablo Simón Marqués,
• Kyohei Matsuo,
• Naoki Aratani,
• Hiroko Yamada,
• Gwénaël Rapenne and
• Claire Kammerer

Beilstein J. Org. Chem. 2024, 20, 287–305, doi:10.3762/bjoc.20.30

• isomers. Finally, reaction of this bisaryne precursor with an excess cesium fluoride and bare isobenzofuran gave rise to the end-capped soluble precursor 59 via a double cycloaddition process. All polyepoxides 58–60 were deposited by sublimation on a Au(111) surface, triggering in some cases partial

Decarboxylative 1,3-dipolar cycloaddition of amino acids for the synthesis of heterocyclic compounds

• Xiaofeng Zhang,
• Xiaoming Ma and
• Wei Zhang

Beilstein J. Org. Chem. 2023, 19, 1677–1693, doi:10.3762/bjoc.19.123

• -type AMYs in multicomponent, one-pot, and stepwise reactions for the synthesis of diverse heterocycles related to some bioactive compounds and natural products. Keywords: [3 + 2] cycloaddition; decarboxylation; 1,3-dipolar; double cycloaddition; one-pot synthesis; multicomponent reaction; semi

• stereoselectivity (Scheme 3) [61][62]. From the results shown in Scheme 2 and Scheme 3, we envisioned that pyrrolidines 3c or 3d generated from the cycloaddition of AMYs B3 or B4 could undergo a second cycloaddition to form double cycloaddition products 4a or 4b (Scheme 4). The double cycloaddition process involves

• two kinds of AMYs, with the first ones (N-H-type B3 or B4) derived from amino acids, while the second ones (N-R-type B1) derived from pyrrolidines 3c or 3d. It is worth noting that the double cycloaddition reaction is a pseudo-five-component reaction of amino acids with two equivalents each of

A novel bis-triazole scaffold accessed via two tandem [3 + 2] cycloaddition events including an uncatalyzed, room temperature azide–alkyne click reaction

• Ksenia Malkova,
• Andrey Bubyrev,
• Vasilisa Krivovicheva,
• Dmitry Dar’in,
• Alexander Bunev and
• Mikhail Krasavin

Beilstein J. Org. Chem. 2022, 18, 1636–1641, doi:10.3762/bjoc.18.175

• (Figure 1). Herein, we report on a successful realization of this strategy. Results and Discussion To test the possibility of a tandem double cycloaddition reaction between 1, an alkyne-containing amine and an azide-containing aldehyde, we set up a reaction of 1 with o-azidobenzaldehyde (3a) and

• -cytotoxic which makes them suitable for interrogation of various biological targets. (a) Previously developed three-component approach to 1,5-disubstituted 1,2,3-triazoles; (b) double cycloaddition strategy investigated in this work. Diversely bioactive compounds based on scaffolds A and B. Aromatic azido

Synthesis and fluorescent properties of N(9)-alkylated 2-amino-6-triazolylpurines and 7-deazapurines

• Andrejs Šišuļins,
• Jonas Bucevičius,
• Yu-Ting Tseng,
• Irina Novosjolova,
• Kaspars Traskovskis,
• Ērika Bizdēna,
• Huan-Tsung Chang,
• Sigitas Tumkevičius and
• Māris Turks

Beilstein J. Org. Chem. 2019, 15, 474–489, doi:10.3762/bjoc.15.41

• towards 2-amino-6-triazolylpurine derivatives was performed in a more atom economic way. The latter synthesis does not require a double cycloaddition followed by replacement of one of the triazole moieties. The final structural proof for the compounds of the series 7a–f and 8a–f was obtained by spectral

Stereodynamic tetrahydrobiisoindole “NU-BIPHEP(O)”s: functionalization, rotational barriers and non-covalent interactions

• Golo Storch,
• Sebastian Pallmann,
• Frank Rominger and
• Oliver Trapp

Beilstein J. Org. Chem. 2016, 12, 1453–1458, doi:10.3762/bjoc.12.141

• functionalization at the secondary amine position, we changed the strategy and used N-Boc dipropargylamine as the diyne compound (Figure 1A). The double cycloaddition product 1c was obtained in 77% yield. In accordance with the report of Doherty et al., very slow addition of the diyne compound via syringe pump was

Domino reactions of 2H-azirines with acylketenes from furan-2,3-diones: Competition between the formation of ortho-fused and bridged heterocyclic systems

• Alexander F. Khlebnikov,
• Mikhail S. Novikov,
• Viktoriia V. Pakalnis,
• Roman O. Iakovenko and
• Dmitry S. Yufit

Beilstein J. Org. Chem. 2014, 10, 784–793, doi:10.3762/bjoc.10.74

• :3′,2′-d]pyrazine skeleton formation revealed a new reaction of 3-aryl-2H-azirines in the presence of acylketenes from furandiones, i.e. acid-catalyzed dimerization to dihydropyrazines followed by consecutive double cycloaddition of the latter to acylketenes. According to the calculations the larger

Brønsted acid-promoted azide–olefin [3 + 2] cycloadditions for the preparation of contiguous aminopolyols: The importance of disiloxane ring size to a diastereoselective, bidirectional approach to zwittermicin A

• Hubert Muchalski,
• Ki Bum Hong and
• Jeffrey N. Johnston

Beilstein J. Org. Chem. 2010, 6, 1206–1210, doi:10.3762/bjoc.6.138

• stereocontrolled construction of the aminopolyol core of (−)-zwittermicin A using an azide–olefin double cycloaddition. Depictions of the likely major conformations of the siloxane (A) and disiloxane (B) rings. Confirmation of the relative stereochemistry of bis(triazoline) 14a. (a) TfOH, CH3CN, rt, 18 h; (b