Total synthesis of the proposed structure of xylarolide

A total synthesis of a proposed structure of xylarolide is described. The key features of the synthesis include Sharpless asymmetric reaction, Wittig olefination, Sharpless asymmetric dihydroxylation, Still-Gennari olefination and Yamaguchi lactonization. The differences in the spectroscopic data of the synthetic and natural product indicate a revision of the assigned structure.     

Total Synthesis of Panaginsene

The total synthesis of panaginsene has been accomplished in 11 linear steps starting from methyl 3,3-dimethyl-5-oxocyclopent-1-ene-1-carboxylate. The key steps are a Sharpless asymmetric epoxidation and Ti(III)-mediated reductive epoxide opening-radical cyclization to construct the chiral quaternary carbon stereocenter followed by a very challenging HWE olefination reaction on an 1,3-keto aldehyde and a late stage McMurry olefination using low valent titanium to construct the highly constrained angular tetrasubstituted olefin in a five-membered ring.     

Synthesis of chalcones and flavanones using Julia-Kocienski olefination

A new application of Julia-Kocienski olefination for the synthesis of chalcones and flavanones has been described. 2-(Benzo[d]thiazol-2-ylsulfonyl)-1-phenylethanones have been developed as new reagents for direct Julia-Kocienski olefination with aldehydes in the presence of a base, afforded chalcones in good to excellent yields. Whereas, 2-(benzo[d]thiazol-2-ylsulfonyl)-1-(2-hydroxyphenyl)ethanone reacted with the aromatic aldehydes to furnish flavanones in good yields via one-pot intra-molecular cyclization.     

Metathesis-based synthesis of 3-methoxy α,β-unsaturated lactones: total synthesis of (R)-kavain and of the C1-C6 fragment of jerangolid D

The total synthesis of (R)-kavain and of the C1-C6 fragment of jerangolid D has been achieved in nine and seven steps, respectively, from commercially available dimethyl d-malate. A metathesis reaction of vinyl ethers and a sulfoxide-modified Julia olefination have been employed as the key steps.     

Total synthesis of the alkaloid (−)-codonopsinine from l-xylose

The enantiopure total synthesis of (−)-codonopsinine is described from commercially available l-xylose in 20% overall yield. The key steps included Julia trans olefination and cascade epoxidation-cyclisation strategies.     

New, diastereoselective synthesis of 1-alkyl-5-alkylidene-3-methylidenepyrrolidin-2-ones

The diastereoselective synthesis of 1-alkyl-5-alkylidene-3-methylidenepyrrolidin-2-ones was readily accomplished in a two-step reaction sequence consisting of the reaction of 2-diethoxyphosphoryl-4-oxoalkanoates with amines followed by Horner-Wadsworth-Emmons olefination of formaldehyde using the intermediate 1-alkyl-5-alkylidene-3-diethoxyphosphorylpyrrolidin-2-ones.     

Stereoselective synthesis of microcarpalide

Microcarpalide is a strong microfilament disrupting agent. The convergent and stereoselective synthesis of microcarpalide was succeeded via Julia olefination and macrolactonization.     

Synthesis of resveratrol, DMU-212 and analogues through a novel Wittig-type olefination promoted by nickel nanoparticles

A novel synthesis of resveratrol, DMU-212 and analogues is presented using benzyl alcohols as phosphorus ylide partners in a one-pot Wittig-type olefination reaction promoted by nickel nanoparticles.     

Total synthesis of Carpatamides A–D

A synthetic strategy was developed for the synthesis of the common core structure of Carpatamides A–D. The total synthesis of Carpatamides A and C was completed in 6 steps and of Carpatamides B and D in 7 steps, by employing the Wittig olefination, olefin cross metathesis and acid amine coupling reactions as key steps.     

Synthesis of enol ethers from lactones using modified Julia olefination reagents: application to the preparation of tri- and tetrasubstituted exoglycals

A new route to substituted exoglycals from the corresponding lactones is described. The enol ethers synthesis via a modified Julia olefination of sugar-derived lactones is extended to substituted benzothiazolyl sulfones to furnish tri- and tetrasubstituted exoglycals.     

An efficient stereoselective synthesis of (+)-deoxoprosophylline

An efficient stereoselective synthesis of (+)-deoxoprosophylline from readily available p-anisaldehyde is described. Key steps in the synthesis include the stereoselective amination of anti-1,2-dibenzyl ether using chlorosulfonyl isocyanate, intermolecular olefination, and Pd-catalyzed intramolecular cyclization.     

Stereoselective synthesis of (+)-radicamine B

A simple and efficient stereoselective synthesis of naturally occurring pyrrolidine alkaloid, radicamine B has been accomplished in 13 steps from the commercially available starting materials with an overall yield of 9.75%. The synthesis utilizes Sharpless asymmetric epoxidation and Horner-Wadsworth-Emmons (HWE) olefination as key steps.     

Direct Catalytic Olefination of Alcohols with Sulfones

The synthesis of terminal, as well as internal, olefins was achieved by the one‐step olefination of alcohols with sulfones catalyzed by a ruthenium pincer complex. Furthermore, performing the reaction with dimethyl sulfone under mild hydrogen pressure provides a direct route for the replacement of alcohol hydroxy groups by methyl groups in one step.     

Stereoselective synthesis of Certonardolsterol D3

The first stereoselective synthesis of Certonardolsterol D₃ was described. Ene reaction and improved allylic oxidation were employed as key steps for efficient construction of the desired 3β,6α,15β-triol steroidal framework. The chiral side chain in Certonardolsterol D₃ was finally introduced by Julia olefination.     

Modified Julia olefination and α aminoxylation reactions mediated convergent synthesis of 1α, 24 (R)-dihydroxyvitamin D3 (tacalcitol)

A convergent synthesis of tacalcitol has been achieved starting from inexpensive and commercially available isovaleraldehyde and easily available Inhoffen-Lythgoe diol. Key steps include a proline catalyzed α aminoxylation and a Julia-Kocienski olefination.     

Julia-Kocienski Olefination: A Tutorial Review

Over the past two decades, Julia-Kocienski olefination has become one of the most powerful and reliable C=C double-bond construction methods typically furnishing E-configured alkenes. This review summarizes the scientific literature of the past decade focusing on the key aspects for successful execution of the olefination step. The main stereoselectivity and yield-determining aspects have been outlined in separate chapters providing all the necessary information for the synthesis of Julia-Kocienski reagents as well as the most commonly used reaction optimization techniques.     

Studies on the synthesis of DNA-damaging part of leinamycin: regioselectivity in Ti(OiPr)4 mediated opening of hydroxy epoxides with carboxylic acids

The preparation of the key intermediate in the synthesis of the DNA damaging fragment of the anticancer antibiotic leinamycin starting from geraniol is described. The synthetic sequence involves the building of a quaternary asymmetric center through kinetic resolution through Sharpless epoxidation followed by the regioselective opening of the resultant enantiomerically pure hydroxyepoxide and intramolecular Wittig-Horner olefination.     

Julia-Kocienski Olefination in the Synthesis of Trisubstituted Alkenes: Recent Progress

Julia-Kocienski olefination, a coupling reaction between a carbonyl component and a sulfone partner, has emerged as a powerful synthetic tool in the preparation of several organic compounds. A number of interesting examples involving particularly the preparation of trisubstituted alkenes along with important observations regarding the stereoselectivity of those reactions have been recently reported. This reviewing work covers the literature for the period 2016–2022 and describes in a comprehensive way the progress and developments of Julia-Kocienski olefination application in the synthesis of trisubstituted alkenes which serve as precursors of natural products and their analogs as well of pharmaceutically interesting/biologically important compounds. Moreover, key methodology results dealing with the investigation of the optimum conditions and stereoselectivities and new modifications and approaches are discussed.     

Studies toward the total synthesis of gambieric acids, potent antifungal polycyclic ethers: convergent synthesis of a fully elaborated GHIJ-ring fragment

A stereocontrolled synthesis of a fully elaborated GHIJ-ring fragment of gambieric acids, which are potent antifungal polycyclic ether natural products, has been accomplished. The synthesis features convergent assembly of the tetracyclic polyether skeleton through aldol coupling/cyclodehydration/reductive etherification processes and stereoselective construction of the J-ring side chain by a CeCl₃-promoted Julia-Kocienski olefination.     

Stereoselective synthesis of the C3-C15 fragment of callyspongiolide

The synthesis of C3-C15 fragment of callyspongiolide, a 14-membered macrolides isolated from the marine sponge Callyspongia sp., which was collected from the Indonesia, is reported. Highlights of the synthesis include construction of E-olefin through Julia-Kocienski olefination, Brown asymmetric allylation and base-induced elimination reactions for propargyl alcohol synthesis.