Enolates ambushed – asymmetric tandem conjugate addition and subsequent enolate trapping with conventional and less traditional electrophiles

• Péter Kisszékelyi and
• Radovan Šebesta

Beilstein J. Org. Chem. 2023, 19, 593–634, doi:10.3762/bjoc.19.44

• addition with Grignard reagents Feringa and co-workers realized the tandem conjugate addition of Grignard reagents to 4-chlorocrotonates 46 [42]. The enolate 47, which was formed in this process, underwent an intramolecular nucleophilic substitution to form cyclopropane derivatives. Thioesters, esters as

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

• fluorination of arylcyclopropane derivatives was reported recently [46][47], difluorinated or oxyfluorinated products were obtained [47]. Notably, anodic fluorination of cyclopropane derivatives bearing arylthio groups gives rise to a variety of possible reaction paths yielding monofluorinated sulfoxides as

Electrogenerated base-promoted cyclopropanation using alkyl 2-chloroacetates

• Kouichi Matsumoto,
• Yuta Hayashi,
• Kengo Hamasaki,
• Mizuki Matsuse,
• Hiyono Suzuki,
• Keiji Nishiwaki and
• Norihito Kawashita

Beilstein J. Org. Chem. 2022, 18, 1116–1122, doi:10.3762/bjoc.18.114

• -chloroacetates in Bu4NBr/DMF using a divided cell equipped with Pt electrodes to produce the corresponding cyclopropane derivatives in moderate yields were discovered. The reaction conditions were optimized, the scope and limitations, as well as scale-up reactions were investigated. The presented method for the

• electrochemical production of cyclopropane derivatives is an environmentally friendly and easy to perform synthetic procedure. Keywords: alkyl 2-chloroacetates; cyclopropane derivatives; divided cell; electro-reduction; Introduction In organic chemistry, cyclopropanes and their related compounds have been

• recognized as important molecules. For example, cyclopropane derivatives are found in both natural products and pharmaceutical products. The cyclopropane skeleton is also found in agrochemicals, especially pyrethroid, as an insecticide, is one important compound. Cyclopropanes also play a significant role in

The preparation and properties of 1,1-difluorocyclopropane derivatives

• Kymbat S. Adekenova,
• Peter B. Wyatt and
• Sergazy M. Adekenov

Beilstein J. Org. Chem. 2021, 17, 245–272, doi:10.3762/bjoc.17.25

• activity; cyclopropanation; difluorocyclopropane derivatives; synthesis; Introduction The chemistry of cyclopropane derivatives is one of the most intensively developing fields of organic chemistry. In the past decade there have been made many investigations to develop new chemo-, regio- and

• stereoselective methods for the synthesis and transformations of cyclopropane derivatives. These investigations gained a significant interest, because cyclopropane and cyclopropene fragments are present in the structures of many biologically active substances, such as antibiotics, anticancer, and antimycotic

Lipophilicity trends upon fluorination of isopropyl, cyclopropyl and 3-oxetanyl groups

• Benjamin Jeffries,
• Zhong Wang,
• Robert I. Troup,
• Anaïs Goupille,
• Jean-Yves Le Questel,
• Charlene Fallan,
• James S. Scott,
• Elisabetta Chiarparin,
• Jérôme Graton and
• Bruno Linclau

Beilstein J. Org. Chem. 2020, 16, 2141–2150, doi:10.3762/bjoc.16.182

• cases, for the same fluorination motif, the cyclopropane derivatives have a lower lipophilicity compared to their acyclic equivalents. It is also useful to compare lipophilicities of acyclic and cyclopropane derivatives in which the isosterism represents conversion of a C–H and C–F bond into a C–C bond

• ). Lipophilicity modulation examples involving fluorinated cyclopropane derivatives (measured experimentally via shake-flask method). Lipophilicity changes upon fluorination of isopropyl, cyclopropane and oxetane rings (Series A, C: measured experimentally via shake-flask method; series B: measured experimentally

Visible-light-induced addition of carboxymethanide to styrene from monochloroacetic acid

• Kaj M. van Vliet,
• Nicole S. van Leeuwen,
• Albert M. Brouwer and
• Bas de Bruin

Beilstein J. Org. Chem. 2020, 16, 398–408, doi:10.3762/bjoc.16.38

• cyclopropanation. We have screened a series of strongly oxidizing photoredox catalysts and various alkenes, but unfortunately we were thus far unsuccessful in obtaining cyclopropane derivatives (see experimental section). Conclusion We have shown that it is possible to use monochloroacetic acid to form two types

Cyclopropene derivatives of aminosugars for metabolic glycoengineering

• Jessica Hassenrück and
• Valentin Wittmann

Beilstein J. Org. Chem. 2019, 15, 584–601, doi:10.3762/bjoc.15.54

• reaction kinetics and their labeling intensities after metabolic incorporation. To determine the efficiencies by which the derivatives are metabolized to sialic acids, we synthesized and investigated the corresponding cyclopropane derivatives because cyclopropenes are not stable under the analysis

• cyclopropene derivatives were not stable under these conditions, an observation that has also been made by Ye and co-workers [27]. Therefore, we decided to investigate the corresponding cyclopropane derivatives instead. We expected them to be stable under the DMB labeling conditions and during the preparation

• retention times with the chosen gradients (Figures S5–S8, Supporting Information File 1). We next performed MGE experiments with cyclopropane derivatives. HEK 293T cells were grown with Ac4ManNCyc(H2), Ac4ManNCp(H2), Ac4ManNCyoc(H2), or DMSO only (solvent control) for two days. Subsequently, cells were

Synthesis of 1,2-divinylcyclopropanes by metal-catalyzed cyclopropanation of 1,3-dienes with cyclopropenes as vinyl carbene precursors

• Jesús González,
• Alba de la Fuente,
• María J. González,
• Laura Díez de Tejada,
• Luis A. López and
• Rubén Vicente

Beilstein J. Org. Chem. 2019, 15, 285–290, doi:10.3762/bjoc.15.25

• ; transition metal catalysis; Introduction Far from being considered exotic molecules, cyclopropane derivatives constitute an interesting class of compounds. Indeed, far over 4000 natural products bearing a cyclopropane ring have been discovered [1][2][3], and cyclopropane-containing molecules are recurrent

Oxidative radical ring-opening/cyclization of cyclopropane derivatives

• Yu Liu,
• Qiao-Lin Wang,
• Zan Chen,
• Cong-Shan Zhou,
• Bi-Quan Xiong,
• Pan-Liang Zhang,
• Chang-An Yang and
• Quan Zhou

Beilstein J. Org. Chem. 2019, 15, 256–278, doi:10.3762/bjoc.15.23

• derivatives has drawn great attention in the past several decades. In this review, recent efforts in the development of oxidative radical ring-opening/cyclization of cyclopropane derivatives, including methylenecyclopropanes, cyclopropyl olefins and cyclopropanols, are described. We hope this review will be

• of sufficient interest for the scientific community to further advance the application of oxidative radical strategies in the ring-opening/cyclization of cyclopropane derivatives. Keywords: cyclopropane derivatives; free radicals; ring-opening/cyclization; Introduction Cyclopropane is a cycloalkane

• can take part in ring-opening reactions under certain conditions. Cyclopropane derivatives, with their three-membered carbocyclic frameworks, have spurred considerable attention especially in the domain of organic and pharmaceutical synthesis because of their highly strained three-membered carbocyclic

Dialkyl dicyanofumarates and dicyanomaleates as versatile building blocks for synthetic organic chemistry and mechanistic studies

• Grzegorz Mlostoń and
• Heinz Heimgartner

Beilstein J. Org. Chem. 2017, 13, 2235–2251, doi:10.3762/bjoc.13.221

• cyclopropane derivatives. The treatment of methyl 3-methyl-2-oxodithiobutanoate with diazomethane at −80 °C in hexane/CH2Cl2 afforded the expected 2-sulfanyl-2-isobutanoyl-2,5-dihydro-1,3,4-thiadiazole. After the addition of E-1a and warming of the mixture to room temperature, the corresponding thiolane as the

Unpredictable cycloisomerization of 1,11-dien-6-ynes by a common cobalt catalyst

• Abdusalom A. Suleymanov,
• Dmitry V. Vasilyev,
• Valentin V. Novikov,
• Yulia V. Nelyubina and
• Dmitry S. Perekalin

Beilstein J. Org. Chem. 2017, 13, 639–643, doi:10.3762/bjoc.13.62

• protons. On the basis of 1H–1H and 1H–13C correlation NMR spectra as well as GC–MS analysis we had assigned the structures of these products as the cyclopropane derivatives with internal 4 and exocyclic 5 double bonds (Scheme 2). Our spectral data correlate well with that of similar compounds, which were

• species 8. Further, intramolecular 1,2- or 1,4-hydrometallation in 8 produces carbene complexes, which give cyclopropane derivatives 4 and 5. In order to broaden the substrate scope, we studied similar reactions of the tetramethyl-substituted dienyne 1c (Scheme 4). As expected, it produced the cyclohexene

Selected synthetic strategies to cyclophanes

• Sambasivarao Kotha,
• Mukesh E. Shirbhate and
• Gopalkrushna T. Waghule

Beilstein J. Org. Chem. 2015, 11, 1274–1331, doi:10.3762/bjoc.11.142

• cyclopropane derivatives 30 (62%) and 32 (44%). Later, Michael addition in the presence of caesium fluoride and benzyltriethylammonium chloride in DMF gave the benzannulated cyclodecanone derivatives 31 (11%) and 33 (10%) (Scheme 2). Oxymercuration – Hantzsch pyridine synthesis: Kondo and Miyake [86] have

Investigations of thiol-modified phenol derivatives for the use in thiol–ene photopolymerizations

• Sebastian Reinelt,
• Monir Tabatabai,
• Urs Karl Fischer,
• Norbert Moszner,
• Andreas Utterodt and
• Helmut Ritter

Beilstein J. Org. Chem. 2014, 10, 1733–1740, doi:10.3762/bjoc.10.180

• ]. Many efforts have been undertaken in the last decades aiming to face and overcome these limitations [1][4][5][6][7][8]. For instance the design of tailored (meth)acrylates based on calix[4]arenes [9][10] or tricyclodecane [11][12] backbones and use of ring-opening monomers as cyclopropane derivatives

Stereocontrolled synthesis of 5-azaspiro[2.3]hexane derivatives as conformationally “frozen” analogues of L-glutamic acid

• Beatrice Bechi,
• David Amantini,
• Cristina Tintori,
• Maurizio Botta and
• Romano di Fabio

Beilstein J. Org. Chem. 2014, 10, 1114–1120, doi:10.3762/bjoc.10.110

• faces of the terminal olefin group, therefore affording both the trans and the cis pair of diasteroisomers. As expected based on data available in literature [41][42], the reaction was highly diastereoselective toward the formation of the two trans cyclopropane derivatives 20a and 20c. Furthermore, a

Branching out at C-2 of septanosides. Synthesis of 2-deoxy-2-C-alkyl/aryl septanosides from a bromo-oxepine

• Supriya Dey and
• Narayanaswamy Jayaraman

Beilstein J. Org. Chem. 2012, 8, 522–527, doi:10.3762/bjoc.8.59

• common bromo-oxepine intermediate, involving C–C bond forming organometallic reactions. Unsaturated, seven-membered septanoside vinyl bromides or bromo-oxepines, obtained through a ring expansion methodology of the cyclopropane derivatives of oxyglycals, displayed a good reactivity towards several

Recent advances in the gold-catalyzed additions to C–C multiple bonds

• He Huang,
• Yu Zhou and
• Hong Liu

Beilstein J. Org. Chem. 2011, 7, 897–936, doi:10.3762/bjoc.7.103

• rearrangement followed by nucleophilic attack of the Boc-protected nitrogen atom. A similar method to synthesize the 2-vinylpiperidin-3-ol 158 by a highly stereoselective gold-catalyzed allene cyclization has been reported (Scheme 27) [72]. The ring expansion of cyclopropane derivatives provides a powerful

An expedient and new synthesis of pyrrolo[1,2-b]pyridazine derivatives

• Rajeshwar Reddy Sagyam,
• Ravinder Buchikonda,
• Jaya Prakash Pitta,
• Himabindu Vurimidi,
• Pratap Reddy Padi and
• Mahesh Reddy Ghanta

Beilstein J. Org. Chem. 2009, 5, No. 66, doi:10.3762/bjoc.5.66

• cycloaddition of dimethyl acetylenedicarboxylate to the Reissert compound of pyridazine [20], the 1,3-dipolar cycloaddition of pyridazinium dichloromethylide generated by the carbene method [21], and the cycloaddition of alkylidene cyclopropane derivatives to pyridazine in the presence of Pd(PPh3)4 [22