71769-38-5Relevant articles and documents
Phosphite-thioether/selenoether Ligands from Carbohydrates: An Easily Accessible Ligand Library for the Asymmetric Hydrogenation of Functionalized and Unfunctionalized Olefins
Margalef, Jèssica,Borràs, Carlota,Alegre, Sabina,Alberico, Elisabetta,Pàmies, Oscar,Diéguez, Montserrat
, p. 2142 - 2168 (2019/04/13)
A large family of phosphite-thioether/selenoether ligands has been easily prepared from accessible L-(+)-tartaric acid and D-(+)-mannitol and applied in the M-catalyzed (M=Ir, Rh) asymmetric hydrogenation of a broad number of substrates (46 in total). Its highly modular architecture has been crucial to maximize the catalytic performance. Improving most of the reported approaches, this ligand family presents a broad substrate scope. By selecting the ligand parameters high enantioselectivities (ee's up to 99 %) have therefore been achieved in a broad range of both, functionalized and unfunctionalized substrates. Interestingly, both enantiomers of the hydrogenation products can be usually achieved by changing the ligand parameters.
Phosphite-Thiother Ligands Derived from Carbohydrates allow the Enantioswitchable Hydrogenation of Cyclic β-Enamides by using either Rh or Ir Catalysts
Margalef, Jèssica,Pàmies, Oscar,Diéguez, Montserrat
, p. 813 - 822 (2017/02/05)
Phosphite-thioether ligands with a simple modular architecture, derived from inexpensive l-(+)-tartaric acid and d-mannitol, have been for the first time successfully applied (ee values up to 99 %) in the synthesis of 2-aminotetralines and 3-aminochromane
Absolute configuration of falcarinol, a potent antitumor agent commonly occurring in plants
Zheng, Guangrong,Lu, Wei,Aisa, Haji A.,Cai, Junchao
, p. 2181 - 2182 (2007/10/03)
The absolute configuration of falcarinol (1) was established by stereoselective total synthesis of the two enantiomers.
Asymmetric syntheses of chiral allylic alcohols
Schneider, Christiane,Kazmaier, Uli
, p. 1314 - 1320 (2007/10/03)
Chiral allylic alcohols 2 can easily be obtained by elimination from iodo ketals 10. These are available from natural sources, or by application of the asymmetric Sharpless dihydroxylation to vinylogous esters 6, subsequent reduction, halogenation and elimination. This protocol allows the synthesis of highly functionalized allylic alcohols, which can be used in asymmetric Claisen rearrangements.
Hydrolysis of (2-deoxy-β-D-glucopyranosyl)pyridinium salts
Huang, Xicai,Surry, Clint,Hiebert, Timothy,Bennet, Andrew J.
, p. 10614 - 10621 (2007/10/03)
The hydrolysis reactions of three (2-deoxy-β-D-glucopyranosyl)pyridinium salts exhibit first-order rate constants that are independent of pH in the range of 4.4-10.1 pH units. Derived second-order rate constants for the hydrolysis reactions of (2-deoxy-β-D-glucopyranosyl)-4′-bromoisoquinolinium bromide (5b) conducted in the presence of nucleophilic monoanions (μ = 2.0) including AcO-, Cl-, Br-, and N3 exhibit a Swain-Scott parameter (s) of 0,03 ± 0.05, indicating that these reactions show no sensitivity to the nature of the anion. However, a substantial quantity of the (2-deoxyglucopyranosyl)pyridinium salt hydrolysis product is formed as a result of a post-rate-limiting reaction involving a nucleophilic anion. Analysis of the product ratios indicates that the first-formed intermediate in the hydrolytic reaction is a solvent-separated ion painmolecule encounter complex. The data allow a calculated estimate of greater than 2.5 × 10-12 s for the lifetime of the glucopyranosyloxocarbenium ion in aqueous solution.
Selective Acetate Hydrolysis of Diastereomers with Porcine Pancreatic Lipase (PPL) as an Access to Useful Chiral Building Blocks
Mulzer, Johann,Greifenberg, Stefan,Beckstett, Anne,Gottwald, Matthias
, p. 1131 - 1136 (2007/10/02)
The diastereomeric mixture of the propargylic acetates 2 was diastereomer selectively hydrolyzed with porcine pancreatic lipase (PPL) in water to give the acetate syn-2 and the alcohol anti-3, both more than 95percent diastereomerically pure.From these pr
MODIFICATION OF THE STRUCTURE OF 2-(HYDROXYIMINO)-3-DEOXYALDONIC ESTERS BY THE NITROSATION OF POLYALKOXYMALONATES OF A NEW TYPE
Kornilov, V. I.,Mikshiev, Yu. M.,Levitan, G. E.,Paidak, B. B.,Eryuzheva, O. V.,et al.
, p. 1111 - 1117 (2007/10/02)
In the reactions of malonic ester with acetalized polyhydroxy anhydrides, oxo forms of sugars, and iodo polyols various types of polyalkoxy malonates were synthesized.The latter, with the aid of several variances of C-nitrosation, were converted into alky
