Access to cyclopropanes with geminal trifluoromethyl and difluoromethylphosphonate groups

• Ita Hajdin,
• Romana Pajkert,
• Mira Keßler,
• Jianlin Han,
• Haibo Mei and
• Gerd-Volker Röschenthaler

Beilstein J. Org. Chem. 2023, 19, 541–549, doi:10.3762/bjoc.19.39

• ). In addition, few examples of difluoromethylphosphonate containing cyclopropanes have been reported to date. These compounds were synthesized either by cyclopropanation of CF2P(O)(OEt)2-containing alkenoates using a Corey–Chaykovsky reagent (sulfaniumyl or oxosulfaniumyl methanides) and diazomethane

Double-headed nucleosides: Synthesis and applications

• Vineet Verma,
• Jyotirmoy Maity,
• Vipin K. Maikhuri,
• Ritika Sharma,
• Himal K. Ganguly and
• Ashok K. Prasad

Beilstein J. Org. Chem. 2021, 17, 1392–1439, doi:10.3762/bjoc.17.98

• . The convergent synthesis of the double-headed nucleosides was achieved from uridine, which was first converted to the 3′,5′-(1,1,3,3-tetraisopropyldisiloxan-1,3-diyl)-protected (TIPDS) ketonucleoside 1 following a standard procedure [40]. The subsequent Corey–Chaykovsky epoxidation [41] of 2

N-tert-Butanesulfinyl imines in the asymmetric synthesis of nitrogen-containing heterocycles

• Joseane A. Mendes,
• Paulo R. R. Costa,
• Miguel Yus,
• Francisco Foubelo and
• Camilla D. Buarque

Beilstein J. Org. Chem. 2021, 17, 1096–1140, doi:10.3762/bjoc.17.86

• combining a nucleophilic addition to N-tert-butanesulfinyl α-chloroimines, and an intramolecular cyclization, the chlorine atom being finally displaced. Chiral N-tert-butanesulfinyl aldimines and ketimines have also been used successfully to form aziridines through aza-Darzens and Corey–Chaykovsky reactions

A review of the total syntheses of triptolide

• Xiang Zhang,
• Zaozao Xiao and
• Hongtao Xu

Beilstein J. Org. Chem. 2019, 15, 1984–1995, doi:10.3762/bjoc.15.194

• new methodologies of butenolide formation. The first butenolide formation started with the reaction of ketone 68 with carbon disulfide (CS2) and iodomethane (MeI) to give the ketene dithioacetal intermediate 69, which was subjected to a Corey–Chaykovsky epoxidation, followed by acid hydrolysis to give

One-pot synthesis of epoxides from benzyl alcohols and aldehydes

• Edwin Alfonzo,
• Jesse W. L. Mendoza and
• Aaron B. Beeler

Beilstein J. Org. Chem. 2018, 14, 2308–2312, doi:10.3762/bjoc.14.205

• through in situ generation of sulfonium salts from benzyl alcohols and their subsequent deprotonation for use in Corey–Chaykovsky epoxidation of aldehydes. The generality of the method is exemplified by the synthesis of 34 epoxides that were made from an array of electronically and sterically varied

• alcohols and aldehydes. Keywords: Corey–Chaykovsky; epoxide; heterocycle; one-pot; ylide; Introduction Epoxides have historically served as strategic functional groups in target-oriented synthesis [1][2][3][4]. Common examples of their utility include stereospecific ring opening [5][6][7], rearrangements

• for a general and operationally simple method to generate benzyl epoxides. One of the most powerful methods to access epoxides is through the Corey–Chaykovsky reaction [21] which uses sulfonium ylides and their subsequent reaction with carbonyl groups. This reaction has seen major advancement since

Biosynthesis of oxygen and nitrogen-containing heterocycles in polyketides

• Franziska Hemmerling and
• Frank Hahn

Beilstein J. Org. Chem. 2016, 12, 1512–1550, doi:10.3762/bjoc.12.148

• example epothilone A (119) and oleandomycin (120) (Figure 4) [123][124][125]. Epoxides result from oxidation of olefins by oxidoreductases, mostly cytochrome P450 monooxygenases or FMOs. Alternative mechanisms, such as reactions between carbenes and carbonyls (analogous to the synthetic Corey–Chaykovsky

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

• ). Then, a systematic study of the reactivity of compound 17 was undertaken to identify the most efficient method to introduce the cyclopropane ring on the sterically hindered, α,β-unsaturated trisubstituted olefin group. With this goal in mind, both the Corey–Chaykovsky [25][26][27] and the Simmons–Smith

• yield compound 22. Corey–Chaykovsky cyclopropanation and Simmons–Smith cyclopropanation protocols were then performed on both derivatives 21 and 22 obtaining only trace amounts of products 23 and 24. Based on this initial set of results, we decided to abandon the synthetic strategy a) and to explore the

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

• DVCPR in an approach towards the core skeleton of tiglianes (like phorbol 206, see Scheme 23), daphnanes and ingenanes [169] in 1980 [170]. Starting from α-bromoenone 198 a Corey–Chaykovsky cyclopropanation reaction was achieved to yield cyclopropane 199. The keto-group was removed using a three step

First synthesis of 2-(benzofuran-2-yl)-6,7-methylene dioxyquinoline-3-carboxylic acid derivatives

• Wentao Gao,
• Jia Liu,
• Yun Jiang and
• Yang Li

Beilstein J. Org. Chem. 2011, 7, 210–217, doi:10.3762/bjoc.7.28

• reactions of 2-hydroxybenzophenones with Corey–Chaykovsky reagent [36], cyclization of 2-acyloxy-1-bromomethylarenes with Cr(II)Cl2/BF3·OEt2 catalyst [37], and boron tribromide-promoted tandem deprotection–cyclization of 2-methoxyphenylacetones [38], 2-methoxyphenylmethanols [39] and 2-hydroxy-3

Mitomycins syntheses: a recent update

• Jean-Christophe Andrez

Beilstein J. Org. Chem. 2009, 5, No. 33, doi:10.3762/bjoc.5.33