23459-13-4Relevant academic research and scientific papers
Copper-Catalyzed Oxy-Alkenylation of Homoallylic Alcohols to Generate Functional syn-1,3-Diol Derivatives
Holt, Dean,Gaunt, Matthew J.
supporting information, p. 7857 - 7861 (2015/06/30)
A novel method for the synthesis of a wide range of functionalized 1,3-diol derivatives is reported. Employing a copper-catalyzed oxy-alkenylation strategy, a range of readily available, substituted homoallylic alcohol derivatives and alkenyl(aryl) iodonium salts combine to form syn-1,3-carbonates in excellent yield and with high selectivity. Furthermore, the products formed are amenable to an iterative reaction sequence, thus affording highly complex polyketide-like fragments. Polyols: The reported copper-catalyzed oxy-alkenylation strategy works well for a range of readily available, substituted homoallylic alcohol derivatives and alkenyl(aryl) iodonium salts to form syn-1,3-carbonates in excellent yield and high selectivity. Furthermore, the products formed are amenable to an iterative reaction sequence, thus affording highly complex polyketide-like fragments.
Substrate range of the titanium TADDOLate catalyzed asymmetric fluorination of activated carbonyl compounds
Bertogg, Andreas,Hintermann, Lukas,Huber, Dominique P.,Perseghini, Mauro,Sanna, Maria,Togni, Antonio
experimental part, p. 353 - 403 (2012/05/07)
The substrate range of the [TiCl2(TADDOLate)] (TADDOL=α,α,α′,α′-tetraaryl-1,3-dioxolane-4, 5-dimethanol)-catalyzed asymmetric α-fluorination of activated β-carbonyl compounds has been investigated. Optimal conditions for catalysis are characterized by using 5 mol-% of TiCl2(naphthalen-1- yl)-TADDOLate) as catalyst in a saturated (0.14 mol/l) MeCN solution of F-TEDA (1-(chloromethyl)-4-fluoro-1,4-diazoniabicyclo[2.2.2]octane bis- [tetrafluoroborate]) at room temperature. A series of α-methylated β-keto esters (3-oxobutanoates, 3-oxopentanoates) with bulky benzyl ester groups (60-90% ee) or phenyl ester (67-88% ee) have been fluorinated readily, whereas α-acyl lactones were also readily fluorinated, but gave lower inductions (13-46% ee). Double stereochemical differentiation in β-keto esters with chiral ester groups raised the stereoselectivity to a diastereomeric ratio (dr) of up to 96.5:3.5. For the first time, β-keto S-thioesters were asymmetrically fluorinated (62-91.5% ee) and chlorinated (83% ee). Lower inductions were observed in fluorinations of 1,3-diketones (up to 40% ee) and β-keto amides (up to 59% ee). General strategies for preparing activated β-carbonyl compounds as important model substrates for asymmetric catalytic α-functionalizations are presented (>60 examples). Copyright
Synthesis, Chemical, and Biological Properties of Vinylogous Hydroxamic Acids: Dual Inhibitors of 5-Lipoxygenase and IL-1 Biosynthesis
Wright, Stephen W.,Harris, Richard R.,Kerr, Janet S.,Green, Alicia M.,Pinto, Donald J.,et al.
, p. 4061 - 4068 (2007/10/02)
Vinylogous hydroxamic acids (3-N-hydroxy-N-alkylamino)-2-propen-1-ones, VHA) were prepared as antiinflammatory agents.The synthesis, chemical properties, and in vitro biological activities of these relatively unexplored compounds are described.The VHAs were prepared by condensation of the appropriate N-substituted hydroxylamine with any of the three reagents: a 1,3-dicarbonyl compound (method A); a vinylogous amide (method B); or an alkynone (method C).The VHAs exist as one or more tautomers in solution with the relative proportions of each being dependent upon the structure of the VHA, solvent, and pH.VHAs undergo some of the typical reactions of hydroxamic acids as well as those of vinylogous amides.VHAs are active as inhibitors of 5-lipoxygenase and of IL-1 biosynthesis in vitro, which do not inhibit other enzymes of the arachidonic acid cascade.They have been shown by ESR studies to bring about inhibition of soybean type 1 15-lipoxygenase by reduction of the active site iron.
