Unusual highly diastereoselective Rh(II)-catalyzed dimerization of 3-diazo-2-arylidenesuccinimides provides access to a new dibenzazulene scaffold

• Anastasia Vepreva,
• Alexander S. Bunev,
• Andrey Yu. Kudinov,
• Grigory Kantin,
• Mikhail Krasavin and
• Dmitry Dar’in

Beilstein J. Org. Chem. 2022, 18, 533–538, doi:10.3762/bjoc.18.55

• intermediate D into cycloheptadiene E is an example of a relatively rare reaction of the cyclopropane-ring expansion through a 1,5-C‒C bond migration [15][16][17]. This concerted process is followed by yet another 1,5-migration of the hydrogen atom, leading to the final dimer 2a. The formation of a single

Diels–Alder reaction of β-fluoro-β-nitrostyrenes with cyclic dienes

• Savva A. Ponomarev,
• Roman V. Larkovich,
• Alexander S. Aldoshin,
• Andrey A. Tabolin,
• Sema L. Ioffe,
• Jonathan Groß,
• Till Opatz and
• Valentine G. Nenajdenko

Beilstein J. Org. Chem. 2021, 17, 283–292, doi:10.3762/bjoc.17.27

• (H5 or H6) and its coupling constant to fluorine (3JH5-F or 3JH6-F). The reaction with 7- and 8-membered cyclic dienes (1,3-cycloheptadiene and 1,3-cyclooctadiene) did not result in the formation of the corresponding cycloadducts confirming that the reaction is very sensitive to the structure of the

• monofluorinated bicyclo[2.2.2]oct-2-enes was obtained in up to 40% yield. The reactivity of CPD and its homologues was evaluated and compared. The reaction rate for CHD proved to be 267 times lower than that for CPD in a model reaction, whereas 1,3-cycloheptadiene and 1,3-cyclooctadiene were found to be unable to

Stereo- and regioselectivity of the hetero-Diels–Alder reaction of nitroso derivatives with conjugated dienes

• Lucie Brulíková,
• Aidan Harrison,
• Marvin J. Miller and
• Jan Hlaváč

Beilstein J. Org. Chem. 2016, 12, 1949–1980, doi:10.3762/bjoc.12.184

• wide range of acyclic and cyclic dienes available for the nitroso hetero-Diels–Alder reaction. Cyclic dienes such as cyclopenta-, cyclohexa- and cycloheptadiene as well as a number of more complex substituted derivatives have been reported as being highly reactive substrates for the reaction [2][74][75

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

• Sebastian Kruger Tanja Gaich Institut für Organische Chemie, Leibniz Universität Hannover, Schneiderberg 1B, 30167 Hannover, Germany 10.3762/bjoc.10.14 Abstract This review summarizes the application of the divinylcyclopropane–cycloheptadiene rearrangement in synthetic organic chemistry. A brief

• overview of the new mechanistic insights concerning the title reaction is provided as well as a condensed account on the biological relevance of the topic. Heteroatom variants of this rearrangement are covered briefly. Keywords: cycloheptadiene; divinylcyclopropane rearrangement; domino reactions; natural

• products; total synthesis; vinylcyclopropane–carbaldehyde rearrangement; Introduction The first documented divinylcyclopropane–cycloheptadiene rearrangement dates back to 1960 occuring during studies of Vogel and coworkers [1][2] on the thermal rearrangement of small carbocycles. Although the desired cis

Gold(I)-catalyzed enantioselective cycloaddition reactions

• Fernando López and
• José L. Mascareñas

Beilstein J. Org. Chem. 2013, 9, 2250–2264, doi:10.3762/bjoc.9.264

• -tuning of the catalyst and substrate is required to achieve excellent enantioselectivities. More recently, Nevado and co-workers have shown that propargyl acetates 4 react with 1,3-dienes in the presence of a gold catalyst to give good yields of cycloheptadiene products of type 5; thus the process could

The preparation of several 1,2,3,4,5-functionalized cyclopentane derivatives

• André S. Kelch,
• Peter G. Jones,
• Ina Dix and
• Henning Hopf

Beilstein J. Org. Chem. 2013, 9, 1705–1712, doi:10.3762/bjoc.9.195

• Tolbert [7]. The preparation of derivatives of 16 better suited for nucleophilic substitution and elimination. Preparation of the pentaacetate 21 from 16. Preparation of the cycloheptadiene octaesters 24/25 according to Diels [11] and Le Goff [13], respectively, followed by ring contraction to the

Asymmetric synthesis of a highly functionalized bicyclo[3.2.2]nonene derivative

• Toshiki Tabuchi,
• Daisuke Urabe and
• Masayuki Inoue

Beilstein J. Org. Chem. 2013, 9, 655–663, doi:10.3762/bjoc.9.74

• optically active cycloheptadiene derivative 7, and its derivatization into bicyclo[3.3.2]decene 1. We assumed that the C4-stereocenter of optically active seven-membered diene 7 would permit the requisite stereoselective Diels–Alder reaction (Scheme 1). Namely, the reaction between 7 and acrolein was

• reaction of 1,4-disubstituted cycloheptadiene derivatives has not been reported [13][14]. Results and Discussion The synthesis of optically active 7 began from crotyl chloride (Scheme 2). The carbon chain extension of crotyl chloride by treatment with acetylacetone and K2CO3 [15], followed by the addition

Ene–yne cross-metathesis with ruthenium carbene catalysts

• Cédric Fischmeister and
• Christian Bruneau

Beilstein J. Org. Chem. 2011, 7, 156–166, doi:10.3762/bjoc.7.22

• conditions to stereoselectively form expanded 7-membered cycloheptadiene products [79]. To avoid ring opening metathesis polymerization of the cyclic olefin, a special procedure involving high dilution and slow syringe pump addition of the olefin had to be used (Scheme 14). The success of this metathesis