89708-65-6Relevant academic research and scientific papers
Atroposelective Synthesis of Axially Chiral N-Arylpyrroles by Chiral-at-Rhodium Catalysis
Chen, Shuming,Han, Feng,Houk, K. N.,Ivlev, Sergei,Meggers, Eric,Xie, Xiulan,Ye, Chen-Xi
supporting information, p. 13552 - 13556 (2020/06/05)
A transformation of fluxional into configurationally stable axially chiral N-arylpyrroles was achieved with a highly atroposelective electrophilic aromatic substitution catalyzed by a chiral-at-metal rhodium Lewis acid. Specifically, N-arylpyrroles were alkylated with N-acryloyl-1H-pyrazole electrophiles in up to 93 percent yield and with up to >99.5 percent ee, and follow-up conversions reveal the synthetic utility of this new method. DFT calculations elucidate the origins of the observed excellent atroposelectivity.
Enantioselective Palladium-Catalyzed Decarboxylative Allylation of β-Keto Esters Assisted by a Thiourea
Qian, Hua,Gu, Guoxian,Zhou, Qinghai,Lu, Jiaxiang,Chung, Lung Wa,Zhang, Xumu
, p. 51 - 56 (2017/10/06)
Enantioselective intramolecular decarboxylative allylation of β-keto esters catalyzed by a palladium bis(phosphine)-thiourea complex is reported. This procedure is not only effective for β-keto esters, but also effective for β-keto amides. An intermolecular variant of the asymmetric decarboxylative allylation is also established. DFT calculations indicate that an outer-sphere mechanism is viable for the decarboxylative allylation of β-keto esters.
Ring expansion of cyclic β-amino alcohols induced by diethylaminosulfur trifluoride: Synthesis of cyclic amines with a tertiary fluorine at C3
Anxionnat, Bruno,Robert, Benoit,George, Pascal,Ricci, Gino,Perrin, Marc-Antoine,Gomez Pardo, Domingo,Cossy, Janine
experimental part, p. 6087 - 6099 (2012/09/11)
As the replacement of a hydrogen atom by a fluorine atom in a compound can have an important impact on its biological properties, the development of methods allowing the introduction of a fluorine atom is of great importance. The scope and limitations of
Solvent-controlled highly selective bis-and monoallylation of active methylene compounds by allyl acetate with palladium(0) nanoparticle
Ranu, Brindaban C.,Chattopadhyay, Kalicharan,Adak, Laksmikanta
, p. 4595 - 4598 (2008/03/12)
(Chemical Equation Presented) Palladium(0) nanoparticle has been used as an efficient catalyst for the allylation of active methylene compounds. Very efficient bisallylation is achieved for a variety of active methylene compounds by allyl acetate and its derivatives in one stroke in THF solvent. The reaction in water provides monoallylated product selectively by allyl acetate only. The recovered Pd(0) nanoparticle is recycled. A probable mechanism is suggested.
Studies on diastereoselective reduction of cyclic β-ketoesters with boron hydrides. Part 4: The reductive profile of functionalized cyclohexanone derivatives
Fraga, Carlos A.M.,Teixeira, Lis Helena P.,Menezes, Carla Maria De S.,Sant'Anna, Carlos Mauricio R.,Ramos, Maria Da Concei??o K.V.,De Aquino Neto, Francisco R.,Barreiro, Eliezer J.
, p. 2745 - 2755 (2007/10/03)
Reduction of 2-allyl-2-carboalkoxycyclohexanones (3d-f), 2-propyl-2-carboethoxycyclohexanone (3g) and 2-benzyl-2- carboethoxycyclohexanone (3h) with boron hydrides in the presence and absence of several chelating agents were studied. Molecular modeling studies using semiempirical PM3 method were performed in order to find a suitable explanation of the diastereoselection of ketone carbonyl faces during the reductive process, which yielded trans-2-allyl-2-carboethoxycyclohexanol (6e) and cis-2-allyl-2-carboethoxycyclohexanol (7e) in good diastereomeric excess by using inexpensive sodium and tetrabutylammonium borohydrides.
Ring-closing metathesis/fragmentation route to geometrically defined medium-ring cycloalkenes: Total synthesis of (±)-periplanone C
Ivkovic, Aleksandar,Matovic, Radomir,Saicic, Radomir N.
, p. 1221 - 1224 (2007/10/03)
The combination of alkene metathesis and β-fragmentation offers an efficient entry into (Z)-configured medium-ring cycloalkenes. The versatility of this method is demonstrated by the total synthesis of Periplanone C, a semiochemical of Periplaneta america
A new tetratertiary phosphine ligand and its use in Pd-catalyzed allylic substitution
Laurenti,Feuerstein,Pepe,Doucet,Santelli
, p. 1633 - 1637 (2007/10/03)
A new tetraphosphine, the cis-cis-cis-1,2,3,4-tetrakis(diphenylphosphinomethyl)cyclopentane (Tedicyp) 1 has been synthesized, characterized, and used in Pd-catalyzed allylic substitutions. The Tedicyp was easily prepared in seven steps from the commercially available himic anhydride. The structure of the complex Tedicyp-borane was determined by X-ray analysis. The tetraphosphine in combination with [Pd(η3-C3H5)Cl]2 affords a very efficient catalyst for allylic substitution of several allylic acetates. Under mild conditions, very high turnover numbers and turnover frequencies have been obtained.
Asymmetric Alkylation Using Chiral Cyclic Diols to Prepare a Quaternary Carbon
Kato, Keisuke,Suemune, Hiroshi,Sakai, Kiyoshi
, p. 3315 - 3326 (2007/10/02)
Asymmetric alkylation of cyclic and acyclic β-keto ester acetals (4, 5, 13, 14, and 18) with C2-symmetric cycloalkane-1,2-dioxy moiety proceeded in a highly diastereoselective manner to afford enol ethers (9-12, 15-17, 19a-c) with a chiral quat
PREPARATION OF OPTICALLY ACTIVE TRICYCLIC 1,4-DIOXEPIN-5-ONE DERIVATIVES AND ITS APPLICATION TO ASYMMETRIC ALKYLATION
Kato, Keisuke,Suemune, Hiroshi,Sakai, Kiyoshi
, p. 413 - 424 (2007/10/02)
Chiral bicyclic α,β-unsaturated lactones (6a,b and 8a,b) were easily synthesized from chiral cyclic diols (2-4) and cyclic β-keto esters (1a,b).Alkylation of 8b proceeded in a highly diastereoselective manner to afford a quaternary carbon.
