Catalytic Isomerization of Olefins and Theirs Derivatives: A Brief Overview

2021 ◽  
Author(s):  
Wangjing Ma ◽  
Bonan Liu ◽  
Duanda Wang ◽  
Jun Zhao ◽  
Lu Zhang ◽  
...  

Carbon–carbon double bond (CCDB) isomerization is a method for synthesizing new organic compounds from olefins and their derivatives, which was based on C=C migration along carbon chain and cis/trans transform, and it plays a vital role in the fields of organic synthesis, synthesis of daily chemicals, raw oil’s development and synthesis of natural products and so on. In this paper, advances of five types of catalytic methods for CCDB of olefins and their derivatives since the 1960s were discussed in detail; Based on his recent work, the author mainly introduces the application and development of photocatalysis in CCDB of olefins and their derivatives.

2019 ◽  
Author(s):  
Siyang Li ◽  
Xiaotong Jiang ◽  
Marie Roveretto ◽  
Christian George ◽  
Ling Liu ◽  
...  

Abstract. Photosensitizing compounds containing brown carbon can absorb UV light and transfer that energy to low volatile organic compounds at the surface of aqueous particles. To better understand the reactivity and photochemical aging processes of organic coating on the aqueous aerosol surface, we have simulated the photosensitized reaction of organic films made of several long chain fatty acids in a Langmuir trough in the presence or absence of irradiation. Several chemicals (imidazole-2-carboxaldehyde and humic acid), PM2.5 samples collected from the field and secondary organic aerosols samples generated from a simulation chamber were used as photosensitizers to be involved in the photochemistry of the organic films. Stearic acid, elaidic acid, oleic acid and two different phospholipids with the same carbon chain length and different degrees of saturation i.e., 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) and 1,2-dioleoylsn-glycero-3-phosphocholine (DOPC) were chosen as the common organic film-forming species in this analysis. The double bond (trans and cis) in unsaturated organic compounds has an effect on the surface area of the organic monolayer. The OA monolayer possessing a cis double bond in an alkyl chain is more expanded than EA monolayers on artificial seawater that contain a photosensitizer. Monitoring the change in the relative area of DOPC monolayers has shown that DOPC does not react with photosensitizers under dark conditions. Instead, the photochemical reaction initiated by the excited photosensitizer and molecular oxygen can generate hydroperoxidation in the DOPC monolayers, accompanied by an increase in the molecular area. The DSPC monolayers did not yield any photochemical oxidized products under the same conditions. The spectra measured with polarization modulation-infrared reflection absorption spectroscopy (PM-IRRAS) were also consistent with the results of a surface pressure-area isotherm. Here, a reaction mechanism explaining these observations is presented and discussed. The results will contribute to our understanding of the processing of organic aerosol aging that controls the aerosol composition.


Science ◽  
2018 ◽  
Vol 361 (6403) ◽  
pp. 664-667 ◽  
Author(s):  
Dainis Kaldre ◽  
Immo Klose ◽  
Nuno Maulide

The chemistry of the carbonyl group is essential to modern organic synthesis. The preparation of substituted, enantioenriched 1,3- or 1,5-dicarbonyls is well developed, as their disconnection naturally follows from the intrinsic polarity of the carbonyl group. By contrast, a general enantioselective access to quaternary stereocenters in acyclic 1,4-dicarbonyl systems remains an unresolved problem, despite the tremendous importance of 2,3-substituted 1,4-dicarbonyl motifs in natural products and drug scaffolds. Here we present a broad enantioselective and stereodivergent strategy to access acyclic, polysubstituted 1,4-dicarbonyls via acid-catalyzed [3,3]-sulfonium rearrangement starting from vinyl sulfoxides and ynamides. The stereochemistry at sulfur governs the absolute sense of chiral induction, whereas the double bond geometry dictates the relative configuration of the final products.


2022 ◽  
Author(s):  
M. Selt ◽  
S. R. Waldvogel

The arylation of organic compounds is a tremendously important tool in organic synthesis, since substituted (het)arenes are essential moieties in many applications ranging from organic intermediates to natural products, pharmaceuticals, and materials. Therefore, an effective, sustainable, and economic synthetic accesses to such compounds is of great demand. This chapter covers the arylation of carbon and heteroatom compounds via an electrooxidative pathway. Direct dehydrogenative methods without the application of a metal catalyst as well as constant-current electrolyses are emphasized. The electrochemical synthesis of biaryl compounds, arylalkanes and arylalkenes, as well as arylated nitrogen, oxygen, and sulfur compounds are described in detail. Additionally, the synthesis of heterocycles through anodic arylation reactions is discussed.


Author(s):  
Anna S. Zalivatskaya ◽  
Dmitriy N. Zakusilo ◽  
Aleksander V. Vasilyev

: Cinnamic acid and cinnamaldehyde may be obtained from renewable plant bio-mass, Cinnamon plants, therefore these compounds should be considered as bio-based platform chemicals for synthesis of novel substances. This review describes recent achievements in organic synthesis based on transformations of cinnamaldehyde, cinnamic acid and its derivatives, focusing, mainly, on the preparation of biologically active compounds. Reactions of these cinnamic derivatives may proceed both onto carbon-carbon double bond and carbonyl group that allows obtaining a wide variety of organic compounds having high synthetic importance and different practically valuable properties, including biological activity.


2005 ◽  
Vol 77 (1) ◽  
pp. 103-117 ◽  
Author(s):  
Anne Baron ◽  
Matthew Ball ◽  
Benjamin Bradshaw ◽  
Sam Donnelly ◽  
Olivier Germay ◽  
...  

Total syntheses of epothilone B and pamamycin 607, which feature reactions between functionalized allylstannanes and aldehydes to introduce a (Z)-trisubstituted double-bond and remote stereocenters stereoselectively, are discussed. Recent work concerned with carrying out this chemistry without the use of allylstannanes as starting materials and progress toward a total synthesis of bryostatins are also presented.


2013 ◽  
Vol 5 (1) ◽  
Author(s):  
Lily M.G. Panggabean ◽  
Abdullah Rasyid ◽  
Zarrah Duniani ◽  
Yana Meliana ◽  
Indah Kurniasih

Trigliceride or triacylglicerol (TAG) composition in crude oil of sixteen strain of marine diatom has been detected by spectra analyses on an Electrospray - Ion Trap – Mass Spectrometry (ESI-IT-MS) HCT Bruker-Daltonic GmbH instrument with AgNO3 used as coordination ionization agent. Biomass samples of each microalga strain were taken from early and late stationary cultures in f/2 enriched seawater and algal oils were extracted according to Bligh and Dyer. Results from spectra analysis showed that P-Pt-P (C16:0-C16:1-C16:0) were distinguished in TAG from diatom strains Chaetoceros sp.1, Chaetoceros sp.2, Thalasiossira sp.1, Thalasiossira sp.2, Thalasiossira sp.3, Navicula sp. 1, Navicula sp. 2, Navicula sp. 3, Navicula sp. 4, Nitzschia sp. 2 and Amphora sp. In contrast, TAGs in Melosira sp. included P-P-P (C16:0-C16:0-C16:0) and P-P-O (C16:0-C16:0-C18:1) were identified. TAGs from Chaetoceros sp. were the most varies among samples, i.e. P-Pt-P (C16:0-C16:1-C16:0), A-P-M (C20:4-C16:0-C14:0), P-Pt-Lt (C16:0-C16:1-C18:3), P-Pt-A (C16:0-C16:1-C20:4), D-P-P (C22:6-C16:0-C16:0), A-Ln-P (C20:4-C18:2-C16:0). Various TAGs were also detected in Nitzschia sp.2, i.e. P-Pt-M (C16:0-C16:1-C14:0), P-Pt-P (C16:0-C16:1-C16:0), P-Pt-S (C16:0-C16:1-C18:0), P-Pt-A (C16:0-C16:1-C20:4). TAGs composition in Skeletonema strains that similar to those in Nitzschia sp.1 has longer carbon, i.e. P-P-O (C16:0-C16:0-C18:1), P-O-O (C16:0-C18:1-C18:1) and O-O-O (C18:1-C18:1-C18:1). TAGs with longer carbon chain and more double bond including highly unsaturated fatty acid C20:4 were increased with culture age in diatoms Chaetoceros sp.1, Chaetoceros sp.2, Thalasiossira sp.2, Navicula sp.1 and Nitzschia sp. 2.Keywords: diatom, TAG, ESI-IT-MS, f/2, early and late stationary


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