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Liu G.,CAS Shanghai Institute of Organic Chemistry
Organic and Biomolecular Chemistry | Year: 2012

Transition metal catalysts have been developed for introducing fluorine into organic compounds. Recent progress in this area is reviewed with an emphasis on the selective fluorination of alkenes, alkynes and allenes. Regio- and stereoselective fluorination reactions are highlighted. This journal is © The Royal Society of Chemistry 2012.

You S.L.,CAS Shanghai Institute of Organic Chemistry
Topics in current chemistry | Year: 2010

Aryl-aryl bond formation constitutes one of the most important subjects in organic synthesis. The recently developed direct arylation reactions for the formation of aryl-aryl bond have emerged as very attractive alternatives to traditional cross-coupling reactions. Particularly, the direct arylation through double C-H activation using the simple arenes as both coupling partners is a highly economic and attractive method. In this chapter, the recent progress of Pd-catalyzed aryl-aryl oxidative coupling reactions through double C-H activation is presented.

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.

Chen Y.-R.,CAS Shanghai Institute of Organic Chemistry | Duan W.-L.,CAS Shanghai Institute of Organic Chemistry
Journal of the American Chemical Society | Year: 2013

A Ag-mediated C-H/P-H functionalization reaction of arylphosphine oxides with internal alkynes was described for the direct preparation of benzo[b]phosphole oxides with a high yield. An unusual aryl migration on the P-atom derived from a C-P bond cleavage and a new C-P bond formation was also observed and demonstrated to proceed via the radical process. © 2013 American Chemical Society.

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.

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