77124-17-5Relevant academic research and scientific papers
Novel and practical asymmetric synthesis of β2,3-amino esters using asymmetric Michael addition of chiral amine
Ozeki, Minoru,Egawa, Honoka,Takano, Toshiki,Mizutani, Hideki,Yasuda, Narumi,Arimitsu, Kenji,Kajimoto, Tetsuya,Hosoi, Shinzo,Iwasaki, Hiroki,Kojima, Naoto,Node, Manabu,Yamashita, Masayuki
supporting information, p. 2014 - 2021 (2017/03/20)
A practical method for the synthesis of chiral β2,3-amino esters having various substituents was developed, which is characterized by an asymmetric Michael addition reaction of a chiral lithium amide with trisubstituted (E)-α,β-unsaturated esters. We found that a highly face-selective protonation occurred by the quick addition of water to the enolate intermediate derived from the Michael addition reaction to afford N-protected β2,3-amino esters in moderate to excellent yields. This finding was made possible by the facile preparation of geometrically pure trisubstituted (E)-α,β-unsaturated esters, which was established recently by our group. The subsequent deprotection of the amino group in the Michael adduct by using N-iodosuccinimide (NIS) efficiently provided β2,3-amino esters having various substituents.
Ni-Catalyzed Regioselective Hydrocarboxylation of Alkynes with CO2 by Using Simple Alcohols as Proton Sources
Wang, Xueqiang,Nakajima, Masaki,Martin, Ruben
supporting information, p. 8924 - 8927 (2015/08/03)
A mild and user-friendly Ni-catalyzed regioselective hydrocarboxylation of alkynes with CO2 (1 bar) is described. This protocol is characterized by a wide scope while obviating the need for sensitive organometallic species and by an unprecedented regioselectivity pattern using simple alcohols as proton sources.
Achiral ligands dramatically enhance rate and enantioselectivity in the Rh/phosphoramidite-catalyzed hydrogenation of α,β-disubstituted unsaturated acids
Hoen, Rob,Boogers, Jeroen A. F.,Bernsmann, Heiko,Minnaard, Adriaan J.,Meetsma, Auke,Tiemersma-Wegman, Theodora D.,De Vries, Andre H. M.,De Vries, Johannes G.,Feringa, Ben L.
, p. 4209 - 4212 (2007/10/03)
(Chemical Equation Presented) Mixing it up: A catalytic system based on a mixed-ligand approach has been developed for the rhodium-catalyzed asymmetric hydrogenation of cinnamic acid derivatives (see scheme, cod = cycloocta-1,5-diene). It is the first time that a catalyst complex based on a heterocombination of a chiral and an achiral monodentate ligand gives dramatically higher enantioselectivity (up to 99%) than any of the corresponding homocomplexes.
Phosphite-Mediated in Situ Carboxyvinylation: A New General Acrylic Acid Synthesis
Brittelli, David R.
, p. 2514 - 2520 (2007/10/02)
Sequential treatment of a 2-halo carboxylic acid with a dialkyl phosphite and an aldehyde or ketone in the presence of 3 equiv of sodium hydride in glyme constitutes a new general acrylic acid synthesis superior to conventional methods.An alkoxide-in-alcohol variant may be used with bromo- or chloroacetic acid and aryl aldehydes to produce cinnamic acids conveniently.The scope and other features of the synthesis are discussed.
