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Search for "cyclopropanation" in Full Text gives 89 result(s) in Beilstein Journal of Organic Chemistry.
Synthetic study toward vibralactone
Beilstein J. Org. Chem. 2025, 21, 2376–2382, doi:10.3762/bjoc.21.182
- featuring a novel Pd-catalyzed β-lactone formation [29]. In addition to these approaches, Nelson and co-workers reported a very concise and impressive total synthesis of vibralactone involving photochemical valence isomerization of substituted pyrone, cyclopropanation, and ring expansion [30]. Zeng, Liu and
Recent advances in Norrish–Yang cyclization and dicarbonyl photoredox reactions for natural product synthesis
Beilstein J. Org. Chem. 2025, 21, 2315–2333, doi:10.3762/bjoc.21.177
- -chloroperoxybenzoic acid) induced epoxidation, which was then followed by a Meinwald rearrangement to accomplish aldehyde 7. From 7, a sequence involving silyl enol ether formation, Simmons−Smith cyclopropanation, and acid-mediated regioselective ring-opening installed the C8 quaternary methyl group in 10. Subsequent
Enantioselective radical chemistry: a bright future ahead
Beilstein J. Org. Chem. 2025, 21, 2283–2296, doi:10.3762/bjoc.21.174
- lactone 26. The Zhang group has extended the chiral metalloradical catalysis to cyclopropanation by the intermolecular reaction between styrenes and ketodiazoacetates [59]. Cyclopropanes were obtained in good yields with high relative and absolute stereocontrol. Properties, such as relatively high earth
Pathway economy in cyclization of 1,n-enynes
Beilstein J. Org. Chem. 2025, 21, 2260–2282, doi:10.3762/bjoc.21.173
- pathway. In THF with trace water, water served as a nucleophile that participated in the reaction, triggering hydroxylation of cyclopropanation intermediate 19 and affording cyclopropane-fused chromanol products 20 (Scheme 5, path a). In anhydrous 1,2-dichloroethane (DCE), gold(I)-catalyzed
- cyclopropanation of 1,6-enyne initiated a cascade involving 1,5-enyne addition, consecutive 1,2-alkyl migrations, and Friedel–Crafts alkylation, efficiently constructing the pentacyclic fused benzofuran framework 21 (Scheme 5, path b). Above two analogues were prepared on a gram scale, converted into valuable
The application of desymmetric enantioselective reduction of cyclic 1,3-dicarbonyl compounds in the total synthesis of terpenoid and alkaloid natural products
Beilstein J. Org. Chem. 2025, 21, 2085–2102, doi:10.3762/bjoc.21.164
- stereoselective cyclopropanation accomplished the first total synthesis of (+)-isochamaecydin (26). On the other hand, starting from 122 and (−)-123, the authors adopted the same procedures as for the synthesis of 125 to obtain the pentacyclic product 126, which underwent the same functional group transformations
Rhodium-catalysed connective synthesis of diverse reactive probes bearing S(VI) electrophilic warheads
Beilstein J. Org. Chem. 2025, 21, 1924–1931, doi:10.3762/bjoc.21.150
- -substrates with the potential to react with metal carbenoids in many different ways [14], for example through O–H, N–H or formal C–H insertion, cyclopropanation, or oxazole [20] formation. The 16 co-substrates, selected from available compounds in our laboratory, are shown in Figure 2 (panel A). Many of
- these substrates had more than one potentially reactive site to enable, for example, O–H insertion (C1–5, C8, C11 and C14), N–H insertion (C3, C6, C12, C13 and C15), formal C–H insertion (C1, C3, C4, C12, C15 and C16), oxazole formation (C9 and C10) and cyclopropanation (C7, C10, C14 and C16). To start
- amine (→ 4-18); cyclopropanation (→ 2-7); and formal C–H insertion into an indole (→ 1-15a and 2-15a) or naphthol (→ 2-4 and 3-4b). In the case of 4 (2-naphthol) and 15 (5-methoxyindole), co-substrates containing functional groups with more than one potentially reactive site, two regioisomeric products
Preparation of a furfural-derived enantioenriched vinyloxazoline building block and exploring its reactivity
Beilstein J. Org. Chem. 2025, 21, 1737–1741, doi:10.3762/bjoc.21.136
- of products in copper-catalyzed 1,4-addition of phenylmagnesium bromide, Giese reaction with 2-iodopropane, Simmons‒Smith or Johnson–Corey–Chaykovsky cyclopropanation, hydroboration reaction with 9-BBN, and Diels–Alders reaction with Danishevsky diene. Gratifyingly, it was found that vinyloxazoline S
Oxetanes: formation, reactivity and total syntheses of natural products
Beilstein J. Org. Chem. 2025, 21, 1324–1373, doi:10.3762/bjoc.21.101
Direct trifluoroethylation of carbonyl sulfoxonium ylides using hypervalent iodine compounds
Beilstein J. Org. Chem. 2024, 20, 3182–3190, doi:10.3762/bjoc.20.263
- reported the α-alkylation of carbonyl sulfoxonium ylides via a Michael addition approach that occurred without any competition from cyclopropanation [30]. While this reaction represented the first direct alkylation of sulfoxonium ylides, it was nonetheless limited to the more reactive ester ylide variants
1,2-Difluoroethylene (HFO-1132): synthesis and chemistry
Beilstein J. Org. Chem. 2024, 20, 1955–1966, doi:10.3762/bjoc.20.171
- -difluoroethylene. Cyclopropanation of 1,2-difluoroethylene. Diels–Alder reaction of 1,2-difluoroethylene and hexachlorocyclopentadiene. Cycloaddition reaction of 1,2-difluoroethylene and fluorinated ketones. Cycloaddition reaction of 1,2-difluoroethylene and perfluorinated aldehydes. Photochemical cycloaddition of
(Bio)isosteres of ortho- and meta-substituted benzenes
Beilstein J. Org. Chem. 2024, 20, 859–890, doi:10.3762/bjoc.20.78
- cyclopropanation [44] (to (±)-66) of α-hydroxy silyl enol ethers (±)-65 followed by an acid-catalysed pinacol rearrangement to (±)-67. As exemplary derivatizations of 5-oxo-BCH (±)-67, 1,5-BCHs (±)-68, (±)-69 and (±)-70 were accessed by reductive amination, ketone reduction, and Horner–Wadsworth–Emmons olefination
- of bridge difluorinated BCPs from α-allyldiazoacetates. In their reaction sequence, intramolecular cyclopropanation first forms the bicyclobutane which is then subjected to CF2 carbene insertion to yield the BCP [76]. Another useful pathway to 1,2,3-BCPs is strain release functionalisation as was
Nucleophilic functionalization of thianthrenium salts under basic conditions
Beilstein J. Org. Chem. 2024, 20, 257–263, doi:10.3762/bjoc.20.26
- -stage C–H functionalization of arenes, Wickens’s group has introduced an oxidative alkene aziridination strategy that relies on thianthrenation of an alkene under electrochemical conditions [27]. Subsequently, cyclopropanation, [28] aziridination, [29] allylic C–H functionalization, [30][31] transition
Exploring the role of halogen bonding in iodonium ylides: insights into unexpected reactivity and reaction control
Beilstein J. Org. Chem. 2023, 19, 1171–1190, doi:10.3762/bjoc.19.86
- have been feasible. In 1989, Moriarty was investigating the intramolecular cyclopropanation of 10 under copper-catalysis, presuming that the reaction would proceed through a metallocarbene intermediate [113]. However, a control experiment showed the reaction to also be viable without catalyst, from
- which the expected product of a free carbene-derived Wolff-type rearrangement was not observed (Scheme 2b). Likewise, Gallos et al. were investigating the intramolecular cyclopropanation of ylide 12, and found that the metal-free reaction proceeded with identical yield and diastereoselectivity as did
- iodobenzene gave 19, and extrusion of SO2 gave 20. In 2010, Moriarty revisited their earlier transformation and reported that the metal-free intramolecular cyclopropanation of 10 to 11 could be achieved in an improved 95% yield by performing the reaction at room temperature rather than 0 °C [11]. The reaction
Copper-catalyzed N-arylation of amines with aryliodonium ylides in water
Beilstein J. Org. Chem. 2023, 19, 1008–1014, doi:10.3762/bjoc.19.76
- , catalyzed by a copper catalyst [39]. Murphy and co-workers reported blue LED-mediated metal-free cyclopropanation of alkenes with iodonium ylides through a diradical intermediate [40]. However, iodonium ylides are relatively unexplored for the arylation of amines. So far only Spyroudis’s group reported N
First synthesis of acylated nitrocyclopropanes
Beilstein J. Org. Chem. 2023, 19, 892–900, doi:10.3762/bjoc.19.67
- ), was subjected to cyclopropanation according to a method described in the literature [13]. To a solution of adduct 4b in toluene, (diacetoxyiodo)benzene and tetrabutylammonium iodide were added, and the resulting mixture was stirred at room temperature for 14 h. Unexpectedly, from the reaction mixture
Enolates ambushed – asymmetric tandem conjugate addition and subsequent enolate trapping with conventional and less traditional electrophiles
Beilstein J. Org. Chem. 2023, 19, 593–634, doi:10.3762/bjoc.19.44
Access to cyclopropanes with geminal trifluoromethyl and difluoromethylphosphonate groups
Beilstein J. Org. Chem. 2023, 19, 541–549, doi:10.3762/bjoc.19.39
- -pentafluoropropylphosphonate, bearing a trifluoromethyl and a difluoromethyl group is reported for the first time. Its application in CuI-catalyzed cyclopropanation reactions with aromatic and aliphatic terminal alkenes under mild reaction conditions is demonstrated. In total, sixteen new cyclopropanes were synthesized in
- good to very good yields. Keywords: alkenes; cyclopropanation; diazo compounds; difluoromethylphosphonate; DFT calculations; Introduction Cyclopropanes constitute a fascinating class of organic compounds due to their unique structure and bond properties [1]. However, their synthetic utility is
- ]. Therefore, as relevant building blocks, tremendous efforts have been made to develop reliable methods for their synthesis. Transition-metal-catalyzed cyclopropanation of alkenes with trifluoromethyldiazoalkanes is a commonly used synthetic strategy for the construction of trifluoromethylcyclopropanes
1,4-Dithianes: attractive C2-building blocks for the synthesis of complex molecular architectures
Beilstein J. Org. Chem. 2023, 19, 115–132, doi:10.3762/bjoc.19.12
- expected allyl cation (3 + 2) cycloaddition reactivity is not operating under gold(I) catalysis, but instead it behaved as a reliable and quite stereoselective vinylgold carbenoid species, affording exclusively cyclopropanation products with a wide range of olefin substrates (Scheme 18c). The carbene-type
- formation of the cis-vinylcyclopropanes (Scheme 18c and 18d). Desulfurization of the adducts again yields the product of a formal cyclopropanation with a ‘naked’ vinyl carbene species, as demonstrated by the stereoselective synthesis of the protected cis-2-vinylcyclopropan-1-amine 123 (Scheme 18d). 7
Total synthesis of grayanane natural products
Beilstein J. Org. Chem. 2022, 18, 1707–1719, doi:10.3762/bjoc.18.181
- synthesis started from 3-hydroxy-2-methoxybenzaldehyde (34), which was converted into Grignard reagent 35 and added onto 3-methylbut-2-enal (Scheme 6). A sequence involving Claisen rearrangement, Roskamp homologation, diazo transfer and intramolecular cyclopropanation led to intermediate 37. The hydroxy
- and 23 steps) to access grayananes with a cyclopentenone moiety on the A ring. It should be noted that although this is a racemic synthesis, intermediate 37 was also synthesized in enantioenriched form using a chiral copper catalyst for the cyclopropanation and a chiral auxiliary on the ester moiety
Synthetic study toward the diterpenoid aberrarone
Beilstein J. Org. Chem. 2022, 18, 1625–1628, doi:10.3762/bjoc.18.173
- were reported [30][31] and more recently, Carreira and co-workers reported [32] the first total synthesis of aberrarone through an impressive cascade reaction including a gold-catalyzed Nazarov cyclization, a cyclopropanation followed by intramolecular aldol reaction to forge the A, B and D rings
Electrogenerated base-promoted cyclopropanation using alkyl 2-chloroacetates
Beilstein J. Org. Chem. 2022, 18, 1116–1122, doi:10.3762/bjoc.18.114
Unusual highly diastereoselective Rh(II)-catalyzed dimerization of 3-diazo-2-arylidenesuccinimides provides access to a new dibenzazulene scaffold
Beilstein J. Org. Chem. 2022, 18, 533–538, doi:10.3762/bjoc.18.55
- formation of a single diastereomer at the cyclopropanation step can be explained by the preferred approach of carbene A from the least sterically hindered side of indene C and the π-stacking interaction of the aromatic fragment of indene and the benzylidene substituent of the carbene. The conversion of
Strategies for the synthesis of brevipolides
Beilstein J. Org. Chem. 2021, 17, 2399–2416, doi:10.3762/bjoc.17.157
- –Smith cyclopropanation; Hyptis brevipes Poit; ring-closing metathesis; Introduction Hyptis brevipes Poit. is an invasive plant species belonging to the mint family Lamiaceae [1][2][3][4]. This plant has been reported to originate from tropical America but is now distributed broadly in other tropical
- commercially available (E)-p-methoxycinnamic acid (17). The vital intermediate 16 is expected from cyclopropyl epoxy alcohol 18, which in turn can be prepared from allylic alcohol 19 via the Furukawa-modified Simmons–Smith cyclopropanation and VO-mediated epoxidation. Acetylfuran (20) is chosen as the six
- influence the stereo-outcome for the later cyclopropanation step. Thus, treatment of 25 with diethylzinc and diiodomethane delivered the expected syn-cyclopropyl carbinol 26 as the major diastereomer (dr 95:5) in 90% yield. After the protection of the secondary alcohol as MOM ether, the primary alcohol was
Asymmetric organocatalyzed synthesis of coumarin derivatives
Beilstein J. Org. Chem. 2021, 17, 1952–1980, doi:10.3762/bjoc.17.128
- of spiroonxindole-cyclopropa[c]coumarins 75 through the cyclopropanation of 3-acylcoumarins 43 and 3-halooxindoles 74 [58]. The authors chose a quinine-derived squaramide catalyst 73 to perform the [2 + 1] cycloaddition. This catalyst reacts with 3-halooxindole, generating an ammonium salt which is
Synthesis of β-triazolylenones via metal-free desulfonylative alkylation of N-tosyl-1,2,3-triazoles
Beilstein J. Org. Chem. 2021, 17, 762–770, doi:10.3762/bjoc.17.66
- many bioactive heterocycles [36]. These are also important precursors of diazo adducts which are used in insertion, cyclopropanation, and various rearrangements to construct various cyclic as well as acyclic moieties under metal-catalysed conditions [37][38]. On the contrary, under basic conditions
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