- Asymmetric hydrogenation of alkenes with planar chiral 2-phosphino-1- aminoferrocene-iridium(I) complexes
-
The first highly enantioenriched and enantiopure planar chiral 2-phosphino-1-aminoferrocene ligands and their Ir(COD)BArF complexes are reported. The ligands display bidentate coordination behavior towards iridium, as indicated by trends in 31P and 1H NMR spectra of the phosphine moieties and the α to nitrogen substituents of the amines. All of the new complexes showed good reactivity as catalysts in promoting asymmetric hydrogenation of several prochiral alkenes, with enantioselectivities up to 92%. Iridium complexes of dimethylaminoferrocene derivatives containing P-Ar groups [PPh2 and P(o-tol)2] gave the highest levels of asymmetric induction.
- Metallinos, Costa,Van Belle, Lori
-
scheme or table
p. 141 - 149
(2011/02/17)
-
- A novel catalytic decarbonylative Heck-type reaction and conjugate addition of aldehydes to unsaturated carbonyl compounds
-
A novel rhodium-catalyzed decarbonylative reaction of aldehydes with unsaturated carbonyl compounds was discovered to generate Heck-type reaction product and conjugate addition product.
- Yang, Luo,Correia, Camille A.,Guo, Xiangyu,Li, Chao-Jun
-
experimental part
p. 5486 - 5489
(2010/10/20)
-
- Chemoenzymatic synthesis of (+)-α-polypodatetraene and methyl (5R,10R,13R)-labda-8-en-15-oate
-
The reported enzymatic resolution products {acetate of (1S,4aS,8aS)-1,2,3, 4,4a,5,6,7,8,8a-decahydro-5,5,8a-trimethyl-2-oxo-trans-naphthalene-1-methanol-2- ethylene acetal} (8aS)-5 (>99% ee)] and [(1R,4aR,8aR)-1,2,3,4,4a,5,6,7,8,8a- decahydro-5,5,8a-trimethyl-2-oxo-trans-naphthalene-1-methanol-2-ethylene acetal (8aR)-4 (98% ee) were converted to (+)-α-polypodatetraene (1) and methyl (5R,10R,13R)-labda-8-en-15-oate (2), respectively. For the synthesis of (5R,10R,13R)-2, chiral isoprene congener (3S)-26 corresponding to the right part of 2 was synthesized based on the lipase-assisted resolution of (±)-2-methyl-3- (p-methoxyphenyl)propanol (17).
- Kinoshita, Masako,Miyake, Takahiro,Arima, Yuusuke,Oguma, Minako,Akita, Hiroyuki
-
p. 118 - 123
(2008/09/17)
-
- Design, synthesis, and evaluation of potent, structurally novel peroxisome proliferator-activated receptor (PPAR) δ-selective agonists
-
A series of 3-(4-alkoxyphenyl)propanoic acid derivatives was prepared as candidate peroxisome proliferator-activated receptor (PPAR) δ-selective agonists, based on our previously discovered potent human PPARα/δ dual agonist TIPP-401 as a lead compound. Structure-activity relationship studies clearly indicated the importance of the chain length of the alkoxy group at the 4-position, and the n-butoxy compound exhibited the most potent PPARδ transactivation activity and highest PPARδ selectivity. The (S)-enantiomer of a representative compound exhibited extremely potent PPARδ transactivation activity, comparable with or somewhat superior to that of the known PPARδ-selective agonist, GW-501516. The representative compound regulated the expression of genes involved in lipid and glucose homeostasis, and should be useful not only as a chemical tool to study PPARδ function, but also as a candidate drug for the treatment of metabolic syndrome.
- Kasuga, Jun-ichi,Nakagome, Izumi,Aoyama, Atsushi,Sako, Kumiko,Ishizawa, Michiyasu,Ogura, Michitaka,Makishima, Makoto,Hirono, Shuichi,Hashimoto, Yuichi,Miyachi, Hiroyuki
-
p. 5177 - 5190
(2008/03/14)
-
- Rhodium-catalyzed heck-type coupling of boronic acids with activated alkenes in an aqueous emulsion
-
Intermolecular couplings between arylboronic acids and activated alkenes catalyzed by a water-soluble tert-bulyl amphosrhodium complex were found to progress at room temperature and generated Heck-type products with high yields and excellent selectivity. Substitution on the alkene component encouraged the formation of products arising from a conjugate addition-protonation process. In the case of Heck product formation, it was necessary to add two equivalents of the alkene component whereby one equivalent is believed to act as a sacrificial hydride acceptor.
- Lautens, Mark,Mancuso, John,Grover, Harpreet
-
p. 2006 - 2014
(2007/10/03)
-
- Transformation of α,β-epoxyesters into 2,3-dideuterioesters promoted by samarium diiodide
-
An easy and general sequenced elimination/reduction process by means of samarium diiodide, in the presence of D2O, provides an efficient method for synthesizing 2,3-dideuterioesters 2. The reaction can be also carried out in the presence of H2O instead of D2O, yielding the corresponding saturated esters 4. Other deuterated esters have been also obtained. A mechanism to explain this synthesis has been proposed.
- Concellon, Jose M.,Bardales, Eva,Llavona, Ricardo
-
p. 1585 - 1588
(2007/10/03)
-
- A simple method for the synthesis of 2-amino-1(4′-methoxyphenyl)-propane
-
Synthesis of 2-amino-1-(4′-methoxyphenyl)-propane (II) starting from p-anisaldehyde (1) in 67% overall yield is described. Key reactions involved Horner-Wadswoth-Emmons olefination of 1 to form the ester 2 and Hoffmann degradation of amide 5 to obtain the amine II.
- Mereyala,Koduru
-
p. 3005 - 3010
(2007/10/03)
-
- Sequential elimination-reduction reactions promoted by samarium diiodide: Synthesis of 2,3-dideuterioesters or -amides
-
A facile and general sequential elimination/reduction process promoted by samarium diiodide provides an efficient method for synthesizing saturated esters or amides 3 from readily available starting materials. The reaction involves a β-elimination of the starting 2-halo-3-hydroxyesters or -amides 1 and subsequent 1,4-reduction of the obtained α,β-unsaturated esters or amides in the presence of H2O. When D2O is used instead of H2O, 2,3-dideuterioesters or -amides 4 are isolated. A mechanism is proposed to account for this synthesis.
- Concellon, Jose M.,Rodriguez-Solla, Humberto
-
p. 4266 - 4271
(2007/10/03)
-
- Ethynylindenyl compounds and derivatives thereof used in the treatment of pain, fever and inflammation
-
Novel ethynylindenyl compounds and derivatives are described. Their use in the treatment of inflammation is also disclosed.
- -
-
-