131348-78-2Relevant academic research and scientific papers
Diastereoselective Rhodium-Catalyzed Hydrogenation of 2-Oxindoles and 3,4-Dihydroquinolones
Schiwek, Christian H.,Jandl, Christian,Bach, Thorsten
supporting information, p. 9468 - 9472 (2020/11/30)
The benzene ring of indolin-2-ones (2-oxindoles) and 3,4-dihydroquinol-2-ones was converted to a saturated cyclohexane ring by hydrogenation in the presence of the rhodium complex Cy(CAAC)Rh(cod)Cl. The stereoselectivity of the process was found to be high with respect to both external substituent R1 within the saturated part of the heterocyclic ring and substituent X on the benzene ring. Twenty-one hexahydroindolin-2(3H)-ones (70-99% yield, dr = 83/17 to >99/1) and twelve octahydro-2(1H)-quinolinones (87-96% yield, dr = 64/36 to >99/1) were obtained with the major diastereoisomer exhibiting the hydrogen atoms in an all-cis arrangement. The high tolerance toward functional groups and the compatibility with existing stereogenic centers are key features of the hydrogenation protocol presented here.
Synthetic Utility of N-Benzoyloxyamides as an Alternative Precursor of Acylnitrenoids for γ-Lactam Formation
Huh, Soohee,Hong, Seung Youn,Chang, Sukbok
, p. 2808 - 2812 (2019/04/17)
Described herein is the development of a new entry of acylnitrenoid precursors for γ-lactam synthesis via an intramolecular C-H amidation reaction. Upon Ir catalysis, N-benzoyloxyamides serve as efficient substrates to afford 5-membered amides. Mechanistic studies revealed that the generation of a putative Ir-carbonylnitrenoid via N-O bond cleavage is facilitated by the chelation of countercations. This protocol offers a convenient and step-economic route to γ-lactams starting from the corresponding carboxylic acids.
First and Highly Stereoselective Synthesis of Both Enantiomers of Octahydroindole-2-phosphonic Acid (OicP)
Viveros-Ceballos, José Luis,Martínez-Toto, Erick Iván,Eustaquio-Armenta, César,Cativiela, Carlos,Ordó?ez, Mario
, p. 6781 - 6787 (2017/12/07)
We report the first stereoselective synthesis of (2R,3aR,7aR)- and (2S,3aS,7aS)-octahydroindole-2-phosphonic acid 2 (OicP derivatives). The key points are the highly diastereoselective synthesis of cis-fused bicyclic (3aR,7aR)- and (3aS,7aS)-pyrrolidin-2-ones 4 through a dynamic kinetic resolution of racemic γ-keto acid (±)-5 with (R)- and (S)-phenylglycinol via Meyers' bicyclic lactams, and the highly diastereoselective addition of trimethyl phosphite to the N-acyliminium ions 3 obtained from 4.
One-Pot Transformation of Simple Furans into Octahydroindole Scaffolds
Kalaitzakis, Dimitris,Triantafyllakis, Myron,Ioannou, Georgios I.,Vassilikogiannakis, Georgios
supporting information, p. 4020 - 4023 (2017/03/27)
A highly efficient and general singlet-oxygen-initiated one-pot transformation of readily accessible furans into octahydroindole scaffolds has been developed.
Highly Selective Hydrogenation of Aromatic Ketones and Phenols Enabled by Cyclic (Amino)(alkyl)carbene Rhodium Complexes
Wei, Yu,Rao, Bin,Cong, Xuefeng,Zeng, Xiaoming
supporting information, p. 9250 - 9253 (2015/08/11)
Air-stable Rh complexes ligated by strongly σ-donating cyclic (amino)(alkyl)carbenes (CAACs) show unique catalytic activity for the selective hydrogenation of aromatic ketones and phenols by reducing the aryl groups. The use of CAAC ligands is essential for achieving high selectivity and conversion. This method is characterized by its good compatibility with unsaturated ketones, esters, carboxylic acids, amides, and amino acids and is scalable without detriment to its efficiency.
Stereodivergent Synthesis of Two Novel α-Aminophosphonic Acids Characterised by a cis-Fused Octahydroindole System
Arizpe, Alicia,Sayago, Francisco J.,Jimenez, Ana I.,Ordonez, Mario,Cativiela, Carlos
experimental part, p. 3074 - 3081 (2011/06/28)
The synthesis of two new α-aminophosphonic acids, namely (2S*,3aS*,7aS)- and (2R*,3aS*,7aS)-octahydroindole-2- phosphonic acids, is described. They are analogues of phosphoproline with a cyclohexane ring fused to the pyrrolidine moiety. The ring junction has cis stereochemistry in both cases, but the two compounds differ in the relative orientation of the cyclohexane and phosphonate moieties. The two amino acids were prepared from a common starting material following stereodivergent routes that provide the desired stereoisomer with complete stereocontrol. The relative configurations of the compounds synthesised were confirmed by X-ray diffraction analysis. Two analogues of phosphoproline with a cyclohexane ring fused to the pyrrolidine moiety have been synthesised. They differ in the stereochemistry at the α-carbon atom and have been prepared, with complete stereocontrol, following stereodivergent routes from a common precursor.
Catalytic asymmetric reductive animation of α-branched ketones
Wakchaure, Vijay N.,Zhou, Jian,Hoffmann, Sebastian,List, Benjamin
supporting information; experimental part, p. 4612 - 4614 (2010/08/07)
Chemical equcation Presented Branching out: An organocatalytic reductive amination of -αbranched ketones using dynamic kinetic resolution is reported. The e/s-2-substituted cyclohexyl amines were obtained in high diastereoselectivity and enantioselectivit
Synthesis and biological evaluation of pyrrolinic isosteres of rilmenidine. Discovery of cis-/trans-dicyclopropylmethyl-(4,5-dimethyl-4,5-dihydro-3H-pyrrol-2-yl)- amine (LNP 509), an I1 imidazoline receptor selective ligand with hypotensive activity
Schann,Bruban,Pompermayer,Feldman,Pfeiffer,Renard,Scalbert,Bousquet,Ehrhardt
, p. 1588 - 1593 (2007/10/03)
To find new compounds selective for purported I1 imidazoline receptors (I1Rs), over I2 imidazoline binding sites (I2BS) and α2-adrenoceptors (α2ARs), a series of pyrrolinic isosteres of rilmenidine has been prepared and their biological activity at I1Rs, I2BS, and α2ARs evaluated. This isosteric replacement provided us with compounds which still bound to I1Rs but not to I2BS nor to α2-ARs. A limited structure-affinity relationship was generated around the heterocyclic moiety of these ligands. One compound in this series, LNP 509 (1e) [cis-/trans-dicyclopropylmethyl-(4,5-dimethyl-4,5-dihydro-3H-pyrrol-2-yl) -amine], had no detectable affinity at α2ARs yet was capable of lowering blood pressure after central administration. These pyrrolinic analogues constitute a new chemical class of imidazoline related compounds with high selectivity for the I1Rs. They could be used as new tools in the study of I1Rs and in the conception of new centrally acting hypotensive drugs.
Preparation of γ- and δ-lactams by ring closure of β,γ-unsaturated amides using trifluoromethanesulfonic acid
Marson, Charles M.,Fallah, Asad
, p. 293 - 296 (2007/10/02)
γ-Lactams and δ-lactams can be prepared by the reaction of β,γ-unsaturated amides with trifluoromethanesulfonic acid.
