129704-13-8Relevant articles and documents
DICARBOXIMIDE-BASED CLATHRATE DESIGN. HOST SYNTHESIS, INCLUSION FORMATION AND X-RAY CRYSTAL STRUCTURES OF A FREE HOST AND OF INCLUSION COMPOUDS WITH 2- AND 3-METHYLCYCLOHEXANONE, 3-METHYLCYCLOPENTANONE, BUTYRONITRILE, PROPAN-1-OL and (-)-FENCHONE GUESTS
Weber, Edwin,Reutel, Christiane,Foces-Foces, Concepcion,Llamas-Saiz, Antonio L.
, p. 159 - 170 (1995)
Crystalline host compounds consisting of a roof-shaped dicarboximide framework and pendant diarylethanol analogous subunits were synthesized and shown to form inclusion complexes with small organic molecules such as alcohols, amines, ketones or polar and apolar organic solvents.Clathrate efficiency and selectivity depend on the particular host structure.The crystal and molecular structures of a free host compound (2a) and inclusion compounds were determined by x-ray diffraction analysis.In all the structures, the hydroxyl group is involved in intramolecular hydrogen bonds and the host and guest molecules are held by lattice forces only.The channels and cavities left in the host matrix are large enough to allow disorder or high thermal displacement parameters of the guest molecules.The local packing coeffecients for all guests are 0.42 on average.
Low ligand loading, highly enantioselective addition of phenylacetylene to aromatic ketones catalyzed by Schiff-base amino alcohols
Chen, Chao,Hong, Liang,Xu, Zhao-Qing,Liu, Lei,Wang, Rui
, p. 2277 - 2280 (2006)
Schiff-base amino alcohols 7a,b derived from L-phenylglycine through three simple steps are found to be highly effective for the enantioselective addition of phenylacetylene to aromatic ketones. When the loading of 7b was 1 mol %, an ee value of up to 95% was obtained. However, when 7b was lowered to 0.1 mol %, a high ee value of 85% was still achieved. A practical solution to synthesize the optically active tertiary propargylic alcohols was described.
Synthesis and structure determination of novel chiral imine-alkoxytitanium complexes
Fleischer, Ralf,Wunderlich, Hartmut,Braun, Manfred
, p. 1063 - 1070 (1998)
The imines 4 containing a diphenylcarbinol moiety serve as chiral ligands in novel enantiomerically pure imine-alkoxytitanium(IV) complexes. Depending on the molar ratio of the starting materials, imines 4 and titanium tetraisopropoxide, mono-chelated complexes 5 or bis-chelated complexes 6/7 result. The latter are formed diastereoselectively and the isomers 6 are main or exclusive products. Their (A) configuration is determined by a crystal-structure analysis of 6b. The bis-ligand complexes 6 or mixtures of 6/7, which are found to be remarkably stable, are used as precursors not only for the reactive dihalo complexes 8a/8b but also for the preparation of the mixed chloroisopropoxytitanium complex 8c.
Enantioselective zinc-mediated conjugate alkynylation of saccharin-derived 1-: Aza -butadienes
Blay, Gonzalo,Castilla, Alvaro,Sanz, David,Sanz-Marco, Amparo,Vila, Carlos,Mu?oz, M. Carmen,Pedro, José R.
, p. 9461 - 9464 (2020)
The enantioselective 1,4-alkynylation of conjugated imines derived from saccharin with aryl- and alkyl-substituted terminal alkynes has been achieved. The reaction mediated by diethylzinc in the presence of a catalytic amount of a bis(hydroxy)malonamide chiral ligand provides the corresponding imines bearing a propargylic stereocenter with moderate yields and fair to excellent enantioselectivities. This journal is
Synthesis of acrylic polymer beads for solid-supported proline-derived organocatalysts
Kristensen, Tor E.,Vestli, Kristian,Fredriksen, Kim A.,Hansen, Finn K.,Hansen, Tore
, p. 2968 - 2971 (2009)
A completely non-chromatographic and highly large-scale adaptable synthesis of acrylic polymer beads containing proline and prolineamides has been developed. Novel monomeric proline (meth)acrylates are prepared from hydroxyproline in only one step. Free-radical copolymerization then gives solid-supported proline organocatalysts directly in as little as two steps overall, without using any prefabricated solid supports, by using either droplet or dispersion polymerization. These affordable acrylic beads have highly favorable and adjustable swelling characteristics and are excellent reusable catalysts for organocatalytic reactions.
Simple primary β-amino alcohols as organocatalysts for the asymmetric Michael addition of β-keto esters to nitroalkenes
Begum, Zubeda,Sannabe, Haruka,Seki, Chigusa,Okuyama, Yuko,Kwon, Eunsang,Uwai, Koji,Tokiwa, Michio,Tokiwa, Suguru,Takeshita, Mitsuhiro,Nakano, Hiroto
, p. 203 - 209 (2021/02/09)
Simple primary β-amino alcohols act as an efficient organocatalysts in the asymmetric Michael addition of β-keto esters with nitroalkenes affording highly pure chiral Michael adducts. Also, both enantiomers of the adducts were obtained, depending on the specific catalyst used and reaction temperature.
Iron-catalysed enantioconvergent Suzuki-Miyaura cross-coupling to afford enantioenriched 1,1-diarylalkanes
Tyrol, Chet C.,Yone, Nang S.,Gallin, Connor F.,Byers, Jeffery A.
supporting information, p. 14661 - 14664 (2020/12/02)
The first stereoconvergent Suzuki-Miyaura cross-coupling reaction was developed to afford enantioenriched 1,1-diarylalkanes. An iron-based complex containing a chiral cyanobis(oxazoline) ligand framework was best to obtain enantioenriched 1,1-diarylalkanes from cross-coupling reactions between unactivated aryl boronic esters and benzylic chlorides. Enhanced yields were obtained when 1,3,5-trimethoxybenzene was used as an additive, which is hypothesized to extend the lifetime of the iron-based catalyst. Exceptional enantioselectivities were obtained with challenging ortho-substituted benzylic chlorides. This journal is
Catalytic Asymmetric Intermolecular Cyclopropanation of a Ketone Carbene Precursor by a Ruthenium(II)-Pheox Complex
Chi, Le Thi Loan,Suharto, Agus,Da, Ho Linh,Chanthamath, Soda,Shibatomi, Kazutaka,Iwasa, Seiji
, p. 951 - 955 (2019/01/25)
The diazo derivative of acetonyl acetate is a useful basic skeleton for the synthesis of cyclopropyl ketones. The intermolecular cyclopropanations of diazo acetoxy acetone with olefins are accomplished by using a novel p-nitro-Ru(II)-diphenyl-Pheox catalyst to give the corresponding optically active cyclopropane derivatives in good yields (up to 95%) with excellent diastereoselectivities (up to 99:1) and enantioselectivities (up to 98% ee). (Figure presented.).
Addition of the Lithium Anion of Diphenylmethanol Methyl/Methoxymethyl Ether to Nonracemic Sulfinimines: Two-Step Asymmetric Synthesis of Diphenylprolinol Methyl Ether and Chiral (Diphenylmethoxymethyl)amines
Reddy, Arava Amaranadha,Prasad, Kavirayani R.
, p. 10776 - 10785 (2018/09/12)
Addition of the lithium anion generated from diphenylmethanol methyl and methoxymethyl ether to nonracemic sulfinimines afforded the corresponding addition products in excellent diastereoselctivity and yields. Deprotection of the MOM as well as sulfinyl groups rendered the enantiopure (diphenylhydroxymethyl)amines in excellent yields. The procedure was applied for a two-step synthesis of diphenylprolinol, a privileged ligand in asymmetric catalysis.
Hybrid-Type Squaramide-Fused Amino Alcohol Organocatalysts for Enantioselective Nitro-Aldol Reaction of Nitromethane with Isatins
Chennapuram, Madhu,Subba Reddy,Seki, Chigusa,Okuyama, Yuko,Kwon, Eunsang,Uwai, Koji,Tokiwa, Michio,Takeshita, Mitsuhiro,Nakano, Hiroto
, p. 1638 - 1646 (2017/04/06)
A series of hybrid-type squaramide-fused amino alcohol (SFAA) catalysts were synthesized, and their catalytic efficiency in the enantioselective nitro-aldol reaction of various isatins with nitromethane has been described. This transformation afforded chiral 3-substituted 3-hydroxyoxindoles in excellent chemical yields (up to 99 %) with high enantioselectivities (up to 95 % ee). The resulting chiral 3-hydroxyoxindoles can be further used as synthetic precursors for the synthesis of several natural products that have a broad spectrum of fascinating biological activities.