119068-85-8Relevant academic research and scientific papers
A Novel Allyl Transfer Coupled with a Grob Fragmentation
Li, Shao-Gang,Chen, Hui-Jun,Yang, Yang-Yang,Wu, Wen-Ju,Wu, Yikang
supporting information, p. 2333 - 2336 (2015/10/29)
A novel acid-promoted rearrangement is disclosed. In the previously unknown transformation, an allyl group migrated to an in situ formed carbocation stabilized by an electron-rich aryl or heteroaryl group, resulting in a stereoselective intramolecular Grob fragmentation. The outcome of the rearrangement observed with an array of substrates can be satisfactorily rationalized using a working hypothesis with the aid of a six-membered transition state similar to those proposed for the anionic oxy-Cope or oxonia-Cope rearrangements, but involving only one instead of two double bonds.
Asymmetric reductive aldol-type reaction with carbonyl compounds using dialkyl tartrate as a chiral ligand
Isoda, Motoyuki,Sato, Kazuyuki,Tokura, Yoriko,Tarui, Atsushi,Omote, Masaaki,Ando, Akira
, p. 956 - 961 (2014/12/11)
An asymmetric reductive aldol-type reaction of α,β-unsaturated esters with carbonyl compounds using Rh catalyst and Et2Zn was investigated. A chiral zinc complex from α,β-unsaturated ester was easily generated as the key intermediate from Et2Zn and Wilkin
Reductive aldol-type reaction of α,β-unsaturated esters with aldehydes or ketones in the presence of Rh catalyst and Et2Zn
Sato, Kazuyuki,Isoda, Motoyuki,Tokura, Yoriko,Omura, Keiko,Tarui, Atsushi,Omote, Masaaki,Kumadaki, Itsumaro,Ando, Akira
, p. 5913 - 5915 (2013/10/21)
The reaction of RhCl(PPh3)3 with Et2Zn easily generated a rhodium-hydride complex (Rh-H) that added to α,β-unsaturated esters to form rhodium enolate complexes by formal 1,4-reduction. These rhodium enolates gave the corre
Reductive Reformatsky-Honda reaction of α,β-unsaturated esters: Facile formation of 1,3-dicarbonyl compounds and β-hydroxy esters
Sato, Kazuyuki,Isoda, Motoyuki,Ohata, Shizuka,Morita, Shuhei,Tarui, Atsushi,Omote, Masaaki,Kumadaki, Itsumaro,Ando, Akira
supporting information; experimental part, p. 510 - 514 (2012/04/23)
The reaction of tris(triphenylphosphine)rhodium chloride [RhCl(PPh 3)3] with diethylzinc (Et2Zn) easily afforded a rhodium-hydride complex that effects the 1,4-reduction of α,β- unsaturated esters to give rhodium enolates. Formation of the rhodium enolate is followed by transmetalation with the zinc species to give a Reformatsky-type reagent, and this reacts with various acid chlorides at the α-position to give β-keto esters. The Reformatsky-type reagent also reacts with various electrophiles such as aldehydes, ketones and acid anhydrides to give the corresponding products in which the electrophiles were introduced reductively at the α-position of α,β-unsaturated esters. Copyright
Iron-catalysed Reformatsky-type reactions
Durandetti, Muriel,Perichon, Jacques
, p. 1542 - 1548 (2007/10/03)
A Reformatsky-type reaction has been developed using iron catalysis in acetonitrile or DMF. Reduction of iron(II) bromide by manganese metal in acetonitrile provides a low-valent iron catalyst, which is the active species; under these conditions, α-chloro
Copper(I)-catalyzed enantio- and diastereoselective tandem reductive aldol reaction
Chuzel, Olivier,Deschamp, Julia,Chausteur, Christophe,Riant, Olivier
, p. 5943 - 5946 (2007/10/03)
(Chemical Equation Presented) An efficient method for the enantioselective tandem reductive aldol reaction of methyl acrylate with aldehydes is reported. By using a copper-(I) precursor and a proper diphosphane ligand, high reactivities can be reached, with TOF up to 40 000 h-1. Taniaphos-based ligands lead to enantioselectivities of up to 97% in the case of the major syn diastereoisomer.
An efficient stereoselective synthesis of (E)- and (Z)-trisubstituted alkenes from unactivated Baylis-Hillman adducts using NaBH4/CuCl 2·2H2O
Das, Biswanath,Banerjee, Joydeep,Majhi, Anjoy,Mahender, Gurram
, p. 9225 - 9227 (2007/10/03)
A convenient and facile stereoselective synthesis of (E)- and (Z)-trisubstituted alkenes has been achieved by treatment of unactivated Baylis-Hillman adducts with NaBH4 in the presence of CuCl 2·2H2O at room temperature for 15 min.
The effect of Lewis acidity in carbonyl coupling reactions
Purkayastha, Biswajit,Deka, Krishna S.,Deka, Dibakar C.
, p. 938 - 940 (2007/10/03)
Relative Lewis acidities of (+)-Pr(hfc)3, (+)-Eu(hfc)3 and (+)-Yb(hfc)3 have been estimated by measuring the induced chemical shift of the aldehydic proton of benzaldehyde in the presence of these lanthanide complexes. The order has been estimated as Pr(hfc)3>Yb(hfc)3?Eu(hfc)3. These lanthanide complexes and a few other non-lanthanide compounds such as BBr3, BF3.OEt2, TiCl4 and SnCl4 have been used as Lewis acid catalysts in a coupling reaction between an aldehyde and (E)-1-methoxy-1-(trimethylsilyloxy)propene. Results show that the chemical yield of the reaction is in the same order as the Lewis acidity of the catalyst used. The observation is in consonant with the expectation that higher is the Lewis acidity more should be degree of activation of the carbonyl base by the Lewis acid.
Diastereoselective heterogeneous catalytic hydrogenation of Baylis- Hillman adducts
Mateus, Cristiano R.,Almeida, Wanda P.,Coelho, Fernando
, p. 2533 - 2536 (2007/10/03)
We describe herein our results concerning a highly diastereoselective heterogeneous hydrogenation of Baylis-Hillman adducts obtained from aromatic aldehydes. The results obtained are complementary to those already described for homogeneous catalytic hydro
Formal total syntheses of (-)-oudemansins A, B and X based on a lipase-catalysed hydrolysis of an acetate
Akita, Hiroyuki,Chen, Cheng Yu,Nagumo, Shinji
, p. 2159 - 2164 (2007/10/02)
A highly stereoselective synthesis of versatile chiral synthons possessing two stereogenic centres and based on the enzyme hydrolysis of an acetate, has been achieved and an application of this to the formal total synthesis of (-)-oudemansins A (1), B (2)
