34352-86-8Relevant academic research and scientific papers
Metal-Free Deoxygenation of Chiral Nitroalkanes: An Easy Entry to α-Substituted Enantiomerically Enriched Nitriles
Pirola, Margherita,Faverio, Chiara,Orlandi, Manuel,Benaglia, Maurizio
supporting information, p. 10247 - 10250 (2021/06/18)
A metal-free, mild and chemodivergent transformation involving nitroalkanes has been developed. Under optimized reaction conditions, in the presence of trichlorosilane and a tertiary amine, aliphatic nitroalkanes were selectively converted into amines or nitriles. Furthermore, when chiral β-substituted nitro compounds were reacted, the stereochemical integrity of the stereocenter was maintained and α-functionalized nitriles were obtained with no loss of enantiomeric excess. The methodology was successfully applied to the synthesis of chiral β-cyano esters, α-aryl alkylnitriles, and TBS-protected cyanohydrins, including direct precursors of four active pharmaceutical ingredients (ibuprofen, tembamide, aegeline and denopamine).
Highly Enantioselective Iridium-Catalyzed Hydrogenation of 2-Aryl Allyl Phthalimides
Cabré, Albert,Romagnoli, Elia,Martínez-Balart, Pol,Verdaguer, Xavier,Riera, Antoni
supporting information, p. 9709 - 9713 (2019/11/19)
The iridium-catalyzed asymmetric hydrogenation of 2-aryl allyl phthalimides to afford enantioenriched β-aryl-β-methyl amines is presented. Recently developed Ir-MaxPHOX catalysts are used for this enantioselective transformation. The mild reaction conditions and the feasible removal of the phthalimido group makes this catalytic method easily scalable and of great interest to afford chiral amines. The importance of this new methodology is exemplified by the formal synthesis of (R)-Lorcaserin, OTS514, and enantiomerically enriched 3-methyl indolines.
Palladium-catalyzed oxidative allylation of bis[(pinacolato)boryl]methane: Synthesis of homoallylic boronic esters
Li, Chunsheng,Li, Meng,Li, Jianxiao,Wu, Wanqing,Jiang, Huanfeng
supporting information, p. 66 - 69 (2017/12/27)
A palladium-catalyzed oxidative allylation of bis[(pinacolato)boryl]methane to afford the corresponding homoallylic organoboronic esters with moderate to excellent yields is reported. This novel transformation provides an efficient strategy for the construction of homoallylic organoboronic esters in one step with a broad substrate scope. It is proposed that the palladium-catalyzed oxidative allylic C-H bond activation process may be involved in the catalytic cycle.
Iridium-Catalyzed Enantioselective Hydrogenation of β,β-Disubstituted Nitroalkenes
Liu, Man,Kong, Duanyang,Li, Meina,Zi, Guofu,Hou, Guohua
supporting information, p. 3875 - 3879 (2016/01/25)
A highly efficient, iridium-catalyzed, enantioselective hydrogenation of β,β-disubstituted nitroalkenes has been developed. Using a complex consisting of iridium and (S,S)-f-spiroPhos as the catalyst, a variety of β,β-disubstituted nitroalkenes were successfully hydrogenated to the corresponding chiral nitroalkanes with excellent enantioselectivities (up to 98% ee) and high turnover numbers (TON=1000).
Unexpected extension of usage of PPh3/CBr4, a versatile reagent: Isomerization of aromatic allylic alcohols
Gong, Wanchun,Liu, Yun,Xue, Jijun,Xie, Zhixiang,Li, Ying
supporting information, p. 1597 - 1599 (2013/02/23)
The PPh3/CBr4-catalyzed isomerization of 2-aromatic allylic alcohols into the corresponding saturated aldehydes or ketones has been achieved at room temperature in good to excellent yields under mild and metal-free conditions. This new methodology has been applied successfully to the synthesis of ibuprofen in four steps.
Formation of 9,10-unsaturation in the mitomycins: Facile fragmentation of β-alkyl-β-aryl-α-oxo-γ-butyrolactones
Ziegler, Frederick E.,Berlin, Michael Y.,Lee, Kyungae,Looker, Adam R.
, p. 3619 - 3621 (2007/10/03)
(matrix presented) A facile fragmentation of β-alkyl-β-aryl-α-oxo-γ-butyrolactones is reported. A study to assist in the elucidation of the mechanism of the reaction is also revealed.
A modification of the asymmetric dihydroxylation approach to the synthesis of (S)-2-arylpropanoic acids
Ishibashi, Hiroyuki,Maeki, Momoe,Yagi, Junko,Ohba, Masashi,Kanai, Tae
, p. 6075 - 6080 (2007/10/03)
Catalytic hydrogenolysis of (S)-2-phenyl-1-2-propanediol (2), prepared by an asymmetric dihydroxylation of α-methylstyrene (1) with AD-mix-α, over Pearlman's catalyst gave (S)-2-phenyl-1-propanol (3). This method was applied to the synthesis of optically active 2-arylpropanoic acid antiinflammatory agents, (S)-ibuprofen (8) and (S)-naproxen (13).
Regio- and stereoselective hydrogenolysis of optically active diols via transfer hydrogenation : Synthesis of α- arylpropionic acids
Nandanan,Jayachandran,Phukan, Prodeep,Pais, Godwin C. G.,Sudalai
, p. 1221 - 1227 (2007/10/03)
Asymmetric synthesis of α-arylpropionic acids, Ibuprofen 1b, Naproxen 1c, and Flurbiprofen 1d have been achieved by employing Sharpless asymmetric dihydroxylation followed by the stereoselective hydrogenolysis of the chiral diols coupled with Jones' oxidation as the key steps. The regio- and stereoselective hydrogenolysis of the chiral diols at the benzylic position proceeds with retention of configuration for all the substrates studied.
IBUPROFEN AND NAPROXEN VIA ORGANOBORANES
Rivera, Isaac,Colberg, Juan C.,Soderquist, John A.
, p. 6919 - 6922 (2007/10/02)
The sequential Pd-catalyzed couplings of aryl bromides and triflates with the appropriate organoboranes provide the key steps in new synthetic routes to both ibuprofen and naproxen in racemic form.
