95547-10-7Relevant academic research and scientific papers
Enantioselective Reductive Coupling of Imines Templated by Chiral Diboron
Chen, Dongping,Li, Kaidi,Tang, Wenjun,Xu, Guangqing,Xu, Ronghua,Zhou, Mingkang
supporting information, p. 10337 - 10342 (2020/07/04)
We herein report a general, practical, and highly efficient method for asymmetric synthesis of a wide range of chiral vicinal diamines via reductive coupling of imines templated by chiral diboron. The protocol features high enantioselectivity and stereospecificity, mild reaction conditions, simple operating procedures, use of readily available starting materials, and a broad substrate scope. The method signifies the generality of diboron-enabled [3,3]-sigmatropic rearrangement.
A telescopic one-pot synthesis of β-lactam rings using amines as a convenient source of imines
Rajam?ki, Suvi H. M.,De Luca, Lidia,Capitta, Francesca,Porcheddu, Andrea
, p. 38553 - 38557 (2016/06/01)
A facile synthetic approach to substituted β-lactams was designed, using secondary benzylic amines and acid chlorides as starting materials. The reactions proceeded smoothly and all the products were obtained in good yields.
Four-Electron Electrocyclic Ring-Opening/Intermolecular [4+2] Cycloadditions of α-Hydroxycyclobutenones: Stereoselective Synthesis of Multiple Substituted δ-Lactams
Song, Peidong,Li, Qing,Wang, Congcong,Wu, Wenfa,Mao, Xu,Wang, Jiajia,Hu, Xiangdong
supporting information, p. 1208 - 1212 (2016/04/26)
A four-electron electrocyclic ring-opening/intermolecular [4+2] cycloaddition of α-hydroxycyclobutenones is reported. The reaction represents the first example for the intermolecular cycloaddition of the extensively studied enol-ketene intermediate, and provides a new synthetic route to multiply substituted δ-lactams in high stereoselectivity.
A latent reaction in a model GFP chromophore revealed upon confinement: Photohydroxylation of ortho -halo benzylidene-3-methylimidazolidiones via an electrocylization process
Samanta, Shampa R.,Da Silva, Jose P.,Baldridge, Anthony,Tolbert, Laren M.,Ramamurthy
supporting information, p. 3304 - 3307 (2014/07/08)
Excited state behavior of halogen substituted model GFP chromophores was investigated in an acetonitrile solution and in a confined environment provided by an octa acid capsule in water. Of the ortho, meta, and para halogen substituted GFP chromophores on
Steric and electronic effects in capsule-confined green fluorescent protein chromophores
Baldridge, Anthony,Samanta, Shampa R.,Jayaraj, Nithyanandhan,Ramamurthy,Tolbert, Laren M.
supporting information; scheme or table, p. 712 - 715 (2011/04/15)
The turn-on of emission in fluorescent protein chromophores sequestered in an "octaacid" capsule is controlled by stereoelectronic effects described by a linear free energy relationship. The stereochemical effects are governed by both the positions and volumes of the aryl substituents, while the electronic effects, including ortho effects, can be treated with Hammett σ parameters. The use of substituent volumes rather than A values reflects packing of the molecule within the confines of the capsule.
Protecting-group-free total synthesis of isoquinoline alkaloids by nickel-catalyzed annulation of o-halobenzaldimine with an alkyne as the key step
Korivi, Rajendra Prasad,Cheng, Chien-Hong
body text, p. 282 - 287 (2010/04/02)
An efficient short total synthesis of benzo[c]phenanthridine alkaloids including oxyavicine, oxynitidine, and oxysanguinarine is described. Thus, N-methyl-o-bromobenzaldimines 1 b-d undergo regioselective cyclization with 4-(benzo[d][1,3]dioxol-5-yl)but-3-yn-1-ol (2b) in the presence of [Ni(cod) 2] (cod = 1,5-cyclooctadiene). In situ oxidation of the resultant isoquinolinium salts gives isoquinolinone derivatives 5b-d with benzo[d][1,3]dioxol-5-yl substitution at the C3 atom and a (CH 2)2OH group at the C4 atom. Later, oxidation of the alcohol group in 5b-d to the aldehyde moiety followed by acid-catalyzed cyclization and dehydration completes the total syntheses to give oxyavicine, oxynitidine, and oxysanguinarine in 67, 65, and 60% yields, respectively. The synthesis requires four steps from o-bromobenzaldehyde derivatives. Transformations of these alkaloids to the other alkaloids in this family are also discussed herein.
Highly stereoselective Friedel-Crafts type cyclization. Facile access to enantiopure 1,4-dihydro-4-phenyl isoquinolinones
Philippe, Nicolas,Denivet, Fran?ois,Vasse, Jean-Luc,Sopkova-De Olivera Santos, Jana,Levacher, Vincent,Dupas, Georges
, p. 8049 - 8056 (2007/10/03)
The present report describes a stereoselective synthesis of 1,4-dihydro-4-phenyl isoquinolinones 5 based on a stereoselective Friedel-Crafts type cyclization. Cyclization precursors 1 were prepared in two steps, from the readily available (S)-mandelic acid, in 60-80% overall yield. The stereoselective electrophilic cyclization was accomplished in 20-86% yield and with 20-97% ee. In the course of this work, the presence of the amide carbonyl was found to be particularly important to guarantee a stereospecific process during the electrophilic aromatic substitution.
