540-08-9Relevant articles and documents
Reactions between lithiated 1,3-dithiane oxides and trialkylboranes
El-Hiti, Gamal A.,Elliott, Mark C.,Saleh, Basil A.,Smith, Keith
, p. 591 - 603 (2021/09/22)
Various 2-substituted-1,3-dithiane oxides (1-oxide and 1,3-dioxide) have been metalated and reacted for the first time with a trialkylborane (trioctylborane). The 2-chloro-1,3-dioxide results in migration of an octyl group from boron to carbon with the displacement of chloride and gives nonanoic acid after oxidation, but there is no evidence for a second migration involving displacement of a sulfenate group. The reaction involving lithiation of the 2-methoxy-1-oxide results in two migrations, with the displacement of both the methoxy group and the thiolate unit of the dithiane ring, giving dioctyl ketone after oxidation, but the yield is low, primarily because thiophilic addition of the lithiating agent predominates over lithiation. Again, there is no evidence for the displacement of the sulfenate unit. However, the intermediate prior to oxidation can be treated with trifluoroacetic anhydride to induce a Pummerer rearrangement, and the presumed trifluoroacetoxyalkylthiolate group then acts as a novel leaving group and is displaced, resulting in trioctylmethanol on oxidation, but the yield is again very low.
IONIZABLE AMINE LIPIDS AND LIPID NANOPARTICLES
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, (2020/11/04)
The disclosure provides ionizable amine lipids and salts thereof (e.g., pharmaceutically acceptable salts thereof) useful for the delivery of biologically active agents, for example delivering biologically active agents to cells to prepare engineered cells. The ionizable amine lipids disclosed herein are useful as ionizable lipids in the formulation of lipid nanoparticle-based compositions.
Long-Range Self-Assembly of an Electron-Deficient Hexaazatrinaphthylene with Out-of-Plane Substituents
Chen, Yi-Ru,Zhang, Yong-Yun,Yeh, Ming-Che,Luo, Ying-Ting,Ong, Chi Wi
, p. 613 - 618 (2019/12/24)
The unprecedented time-dependent long-range supramol-ecular assembly of electron-deficient hexaazatrinaphthylene (HATN) core based on peripheral crowding with three out-of-plane cyclic ketals is reported. The single-crystal X-ray structure of the diethyl derivative provided detailed information as to how four molecules in a repeating unit were packed in order to avoid steric crowding of the out-of-plane cyclic ketal side chain, providing locking and fastening for stabilizing the self-assembled structure. The polarizing optical microscopy (POM) and differential scanning calorimetry (DSC) did not instantaneously show any phase transition upon the cooling process. To our surprise, POM images showed a nucleation of spherulite up to 100 μm after 24 hour later. X-ray diffraction data further confirmed that these soft crystal formed a hexagonal-like crystal. The long-range self-assembly of the new material showed a slight red shift in the UV-vis absorption spectra and further substantiated by computational method.
From Alkyl Halides to Ketones: Nickel-Catalyzed Reductive Carbonylation Utilizing Ethyl Chloroformate as the Carbonyl Source
Shi, Renyi,Hu, Xile
supporting information, p. 7454 - 7458 (2019/04/30)
Ketones are an important class of molecules in synthetic and medicinal chemistry. Rapid and modular synthesis of ketones remains in high demand. Described here is a nickel-catalyzed three-component reductive carbonylation method for the synthesis of dialkyl ketones. A wide range of both symmetric and asymmetric dialkyl ketones can be accessed from alkyl halides and a safe CO source, ethyl chloroformate. The approach offers complementary substrate scope to existing carbonylation methods while avoiding the use of either toxic CO or metal carbonyl reagents.
IONIZABLE CATIONIC LIPID FOR RNA DELIVERY
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, (2018/07/04)
What is described is a compound of formula I consisting of a compound in which R1 is a branched chain alkyl consisting of 10 to 31 carbons; R2 is a linear alkyl, alkenyl, or alkynyl consisting of 2 to 20 carbons; L1 and L2 are the same or different, each a linear alkylene of 1 to 20 carbons or a linear alkenylene of 2 to 20 carbons; X1 is S or O; R3 is a linear or branched alkylene consisting of 1 to 6 carbons; and R4 and R5 are the same or different, each a hydrogen or a linear or branched alkyl consisting of 1 to 6 carbons; or a pharmaceutically acceptable salt thereof.
IONIZABLE CATIONIC LIPID FOR RNA DELIVERY
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Paragraph 0389; 0390; 0391, (2018/07/05)
What is described is a compound of formula I consisting of a compound in which R1 is a branched chain alkyl consisting of 10 to 31 carbons;R2 is a linear alkyl, alkenyl, or alkynyl consisting of 2 to 20 carbons, or a branched chain alkyl consisting of 10 to 31 carbons;L1 and L2 are the same or different, each a linear alkane of 1 to 20 carbons or a linear alkene of 2 to 20 carbons;X1 is S or O;R3 is a linear or branched alkylene consisting of 1 to 6 carbons; andR4 and R5 are the same or different, each a hydrogen or a linear or branched alkyl consisting of 1 to 6 carbons; or a pharmaceutically acceptable salt thereof.
Reactions of organoboranes with carbanions bearing three potential leaving groups: unusual processes, products and mechanisms
Saleh, Basil A.,Smith, Keith,Elliott, Mark C.,Jones, D. Heulyn,Kariuki, Benson M.,El Hiti, Gamal A.
, p. 6914 - 6928 (2016/10/14)
Known reagents that transfer three alkyl groups of a trialkylborane intramolecularly to a single carbon atom lack features to influence stereochemistry. We have investigated four reagents of type LiCCl2X, where X might be amenable to variation. All behaved differently. With X=OR (R=cyclohexyl, menthyl), the reagent decomposed, leading to only low yields of triple migration products. With X=S(O)Ph, a single migration occurred, followed by isomerisation to boron enolate-like species that hydrolysed to α-chloroalkyl phenyl sulfoxides or reacted with aldehydes to aldol-like products. With X=SO2Ph, the major product was the corresponding α,α-dichloroalkyl phenyl sulfone, apparently formed through a redox reaction. With X=S(O)(NMe)Ph, products of three intramolecular alkyl migrations were obtained with unhindered trialkylboranes. Attempts have been made to gain understanding of the sulfoxide process by investigating proportions of aldol-like products, using X-ray crystallography and ab initio calculations.
Factors affecting reactions of trialkylcyanoborates with imidoyl chlorides/trifluoroacetic anhydride
Jones, Dyfyr Heulyn,Smith, Keith,Elliott, Mark C.,El-Hiti, Gamal A.
, p. 6285 - 6289 (2015/08/03)
Abstract Methods for generating tert-alkyl organoboron species are in high demand as they are invaluable intermediates for the synthesis of quaternary carbon centres. Herein we report investigations into generation of tert-alkyl organoboron species using imidoyl chlorides as reagents in the organoboron cyanidation reaction. Although alkenyl side-products predominate in particularly hindered cases, tert-alkyl organoboron species can be successfully generated for less hindered examples.
Stoichiometric reactions of acylnickel(II) complexes with electrophiles and the catalytic synthesis of ketones
Wotal, Alexander C.,Ribson, Ryan D.,Weix, Daniel J.
supporting information, p. 5874 - 5881 (2015/01/09)
Acylnickel(II) complexes feature prominently in cross-electrophile coupling (XEC) reactions that form ketones, yet their reactivity has not been systematically investigated. We present here our studies on the reactivity of acylnickel(II) complexes with a series of carbon electrophiles. Bromobenzene, α-chloroethylbenzene, bromooctane, and iodooctane were reacted with (dtbbpy)NiII(C(O)C5H11)(Br) (1b) and (dtbbpy)NiII(C(O)tolyl)(Br) (1c) to form a variety of organic products. While reactions with bromobenzene formed complex mixtures of ketones, reactions with α-chloroethylbenzene were highly selective for the cross-ketone product. Reactions with iodooctane and bromooctane also produced the cross-ketone product, but in intermediate yield and selectivity. In most cases the presence or absence of a chemical reductant (zinc) had only a small effect on the selectivity of the reaction. The coupling of 1c with iodooctane (60% yield) was translated into a catalytic reaction, the carbonylative coupling of bromoarenes with primary bromoalkanes (six examples, 60% average yield).
Continuous flow synthesis of ketones from carbon dioxide and organolithium or grignard reagents
Wu, Jie,Yang, Xiaoqing,He, Zhi,Mao, Xianwen,Hatton, T. Alan,Jamison, Timothy F.
supporting information, p. 8416 - 8420 (2014/08/18)
We describe an efficient continuous flow synthesis of ketones from CO 2 and organolithium or Grignard reagents that exhibits significant advantages over conventional batch conditions in suppressing undesired symmetric ketone and tertiary alcohol byproducts. We observed an unprecedented solvent-dependence of the organolithium reactivity, the key factor in governing selectivity during the flow process. A facile, telescoped three-step-one-flow process for the preparation of ketones in a modular fashion through the in-line generation of organometallic reagents is also established.
