CAS Shanghai Institute of Organic Chemistry | Date: 2016-03-23
The present invention discloses a catalytic system for preparing highly branched alkane from olefin, which contains novel nickel or palladium complexes. In the presence of the catalytic system, highly branched oily alkane mixture can be efficiently obtained from olefins (such as ethylene) under mild conditions. The alkane mixture has a low bromine number, and can be used as a processing aid(s) and lubricant base oil with high-performance. Provides also was a method for preparing the catalyst and a method for preparing an oily olefin polymer.
Harvard University and CAS Shanghai Institute of Organic Chemistry | Date: 2016-08-26
Ni C.,CAS Shanghai Institute of Organic Chemistry |
Hu M.,CAS Shanghai Institute of Organic Chemistry |
Hu J.,CAS Shanghai Institute of Organic Chemistry
Chemical Reviews | Year: 2015
Organofluorine compounds and materials have found wide applications. Sulfur and fluorine truly form a good partnership in modulating many different types of fluorination and fluoroalkylation reactions through various sulfur/fluorine-containing inorganic and organic compounds/reagents. The historical development of deoxygenative fluorination reagents along the path from SF4, DAST, Deoxo-Fluor to XtalFluors and Fluolead, clearly demonstrates the excellent modulating ability of sulfur-containing groups for efficient and safe fluorination reagents. On the other hand, fluorinated organosulfur compounds, such as sulfones, sulfoximines, sulfinate salts, sulfoxides, sulfilimines, sulfides, among others, often exhibit unique chemical reactivities that are different from their nonfluorinated counterparts. Sulfur-based fluorination and fluoroalkylation reagents will continue to find wide applications in synthesizing new fluorine-containing pharmaceuticals, agrochemicals, and advanced materials.
Zheng C.,CAS Shanghai Institute of Organic Chemistry |
You S.-L.,CAS Shanghai Institute of Organic Chemistry
Chemical Society Reviews | Year: 2012
In recent years, Hantzsch esters and their related organic hydride donors have been widely utilized in biomimetic approaches of asymmetric transfer hydrogenation (ATH) reactions. Various compounds containing C = C, C = N and C = O unsaturated functionalities could be reduced in the presence of organocatalysts or transition metal complexes, affording versatile chiral building blocks in high yields and excellent enantioselectivities under mild conditions. In this critical review, recent advances in this area are summarized and classified according to unsaturated functional groups being reduced and catalytic systems employed. © The Royal Society of Chemistry 2012.
Chu L.,CAS Shanghai Institute of Organic Chemistry |
Qing F.-L.,CAS Shanghai Institute of Organic Chemistry |
Qing F.-L.,Donghua University
Accounts of Chemical Research | Year: 2014
ConspectusThe trifluoromethyl group is widely prevalent in many pharmaceuticals and agrochemicals because its incorporation into drug candidates could enhance chemical and metabolic stability, improve lipophilicity and bioavailability, and increase the protein bind affinity. Consequently, extensive attention has been devoted toward the development of efficient and versatile methods for introducing the CF3 group into various organic molecules. Direct trifluoromethylation reaction has become one of the most efficient and important approaches for constructing carbon-CF3 bonds. Traditionally, the nucleophilic trifluoromethylation reaction involves an electrophile and the CF3 anion, while the electrophilic trifluoromethylation reaction involves a nucleophile and the CF3 cation. In 2010, we proposed the concept of oxidative trifluoromethylation: the reaction of nucleophilic substrates and nucleophilic trifluoromethylation reagents in the presence of oxidants.In this Account, we describe our recent studies of oxidative trifluoromethylation reactions of various nucleophiles with CF3SiMe3 in the presence of oxidants. We have focused most of our efforts on constructing carbon-CF3 bonds via direct trifluoromethylation of various C-H bonds. We have demonstrated copper-mediated or -catalyzed or metal-free oxidative C-H trifluoromethylation of terminal alkynes, tertiary amines, arenes and heteroarenes, and terminal alkenes. Besides various C-H bonds, aryl boronic acids proved to be viable nucleophilic coupling partners for copper-mediated or -catalyzed cross-coupling reactions with CF3SiMe3. To further expand the reaction scope, we also applied H-phosphonates to the oxidative trifluoromethylation system to construct P-CF3 bonds. Most recently, we developed silver-catalyzed hydrotrifluoromethylation of unactivated olefins. These studies explore boronic acids, C-H bonds, and P-H bonds as novel nucleophiles in transition-metal- mediated or -catalyzed cross-coupling reactions with CF3SiMe 3, opening new viewpoints for future trifluoromethylation reactions. Furthermore, we also achieved the oxidative trifluoromethylthiolation reactions of aryl boronic acids and terminal alkynes to construct carbon-SCF3 bonds by using CF3SiMe3 and elemental sulfur as the nucleophilic trifluoromethylthiolating reagent. These oxidative trifluoromethylation and trifluoromethylthiolation reactions tolerate a wide range of functional groups, affording a diverse array of CF3- and CF3S-containing compounds with high efficiencies, and provide elegant and complementary alternatives to classical trifluoromethylation and trifluoromethylthiolation reactions. Because of the importance of the CF 3 and SCF3 moieties in pharmaceuticals and agrochemicals, these reactions would have potential applications in the life science fields. © 2014 American Chemical Society.
Ding C.-H.,CAS Shanghai Institute of Organic Chemistry |
Hou X.-L.,CAS Shanghai Institute of Organic Chemistry
Chemical Reviews | Year: 2011
Developments of catalytic propargylation reactions are presented. Optically active α-oxazolidinonylallenylstannane, prepared from N-propargyloxazolidinone via a lithiation/stannylation sequence, is an efficient reagent for the asymmetric propargylation of carbonyl compounds. Lai and Soderquist successfully extended the use of chiral organoborane regents containing the 10-trimethylsilyl-9-borabicyclo[3.3.2]-decane (10-TMS-9-BBD) ring system. Denmark and Wynn demonstrated that a weak achiral Lewis acid such as SiCl4 can be activated by a chiral Lewis base to afford a strong chiral Lewis acid. Cozzi, Umani-Ronchi, and co-workers developed the first catalytic enantioselective addition of allylic chloride to aldehydes using the chiral complex [Cr(Salen)] as the catalyst. A transition metal-catalyzed asymmetric version of Friedel-Crafts-type propargylation has been developed by using chiral thiolate-bridge diruthenium complexes.
Wei Y.,CAS Shanghai Institute of Organic Chemistry |
Shi M.,CAS Shanghai Institute of Organic Chemistry
Chemical Reviews | Year: 2013
The latest issue of Chemical Reviews focused on the advancements in asymmetric Morita-Baylis-Hillman (MBH)/aza-MBH reactions from 2009 to 2011. Several researchers conducted kinetic and theoretical studies on the MBH mechanism, while others performed an extensive theoretical study, which supported their own kinetic observations and those of McQuade about the proton transfer step. Two distinct pathways leading to the products were proposed, including a second molecule of aldehyde participates the reaction to form a hemiacetal alkoxide hemi1 followed by rate-limiting proton transfer as proposed by McQuade. Some other researchers presented a detailed computational and experimental reinvestigation on the amine-catalyzed MBH reaction of benzaldehyde with methyl acrylate. Another team of researchers also investigated the mechanism of aza-MBH via the ESI-MS(/MS) technique and proposed a rational mechanism for the aza-MBH reaction. This team monitored the DABCO-catalyzed aza-MBH reaction of methyl acrylate 2 with imine 12 by ESI-MS(/MS) spectrometry and intercepted the key intermediates and a unique bissulfonamide intermediate.
Wei Y.,CAS Shanghai Institute of Organic Chemistry |
Shi M.,CAS Shanghai Institute of Organic Chemistry
Accounts of Chemical Research | Year: 2010
Catalytic asymmetric synthesis has received considerable attention over the past few decades, becoming a highly dynamic area of chemical research with significant contributions to the field of organic synthesis. In the development of new catalysts, the concept of multifunctional catalysis described by Shibasaki and co-workers, namely, the combination of more than one functional group within a single molecule to activate the transformation, has proved a powerful strategy in the design of efficient transition metal-containing catalysts. A variety of reactions have since been addressed with multifunctional organocatalysts. One example is the Morita-Baylis-Hillman (MBH) reaction, in which a carbon-carbon bond is created between the α-position of an activated double-bond compound and a carbon electrophile. The seminal report on this reaction in 1972 described the prototypical couplings of (i) ethyl acrylate with acetaldehyde and (ii) acrylonitrile with acetaldehyde; the reaction is promoted by the conjugate addition of a nucleophilic catalyst to the α,β-unsaturated aldehyde. Many variations of the MBH reaction have been reported, such as the aza-MBH reaction, in which an N-tosyl imine stands in for acetaldehyde. Recent innovations include the development of chiral molecules that catalyze the production of asymmetric products. In this Account, we describe the refinement of catalysts for the MBH and related reactions, highlighting a series of multifunctional chiral phosphines that we have developed and synthesized over the past decade. We also review similar catalysts developed by other groups. These multifunctional chiral phosphines, which contain Lewis basic and Brønsted acidic sites within one molecule, provide good-to-excellent reactivities and stereoselectivities in the asymmetric aza-MBH reaction, the MBH reaction, and other related reactions. We demonstrate that the reactivities and enantioselectivies of these multifunctional chiral phosphines can be adjusted by enhancing the reactive center's nucleophilicity, which can be finely tuned by varying nearby hydrogen-bonding donors. Artificial catalysts now provide highly economic access to many desirable compounds, but the general adaptability and reactivity of these platforms remain problematic, particularly in comparison to nature's catalysts, enzymes. The multifunctional organocatalysts described in this Account represent another positive step in the synthetic chemist's efforts to profitably mimic nature's catalytic platform, helping develop small-molecule catalysts with enzyme-like reactivities and selectivities. © 2010 American Chemical Society.
CAS Shanghai Institute of Organic Chemistry | Date: 2016-06-29
The present invention relates to a bimetallic catalyst for olefin polymerization, a preparation method therefor, and the application thereof in catalysis for olefin polymerization. The catalyst is a transitional bimetallic complex of the VIII group with a type of multidentate ligand, and the structural formula thereof is shown as formula (I), wherein the definition for each radical group is described in the description. The catalyst of the present invention has a high activity and a high catalytic efficiency, suitable for olefin polymerization reactions, particularly suitable for the preparation of an olefin polymer having a bimodal distribution of molecular weights.
Harvard University and CAS Shanghai Institute of Organic Chemistry | Date: 2016-06-27
A compound having the following structure (I): or a pharmaceutically acceptable salt, prodrug, stereoisomer or tautomer thereof, is provided. Related compounds, methods for preparation of the same and uses of the compounds for treatment of various indications, including treatment of necrotic cell diseases and/or inflammation, are also provided.