5460-63-9Relevant academic research and scientific papers
Decarboxylative alkenylation
Edwards, Jacob T.,Merchant, Rohan R.,McClymont, Kyle S.,Knouse, Kyle W.,Qin, Tian,Malins, Lara R.,Vokits, Benjamin,Shaw, Scott A.,Bao, Deng-Hui,Wei, Fu-Liang,Zhou, Ting,Eastgate, Martin D.,Baran, Phil S.
, p. 213 - 218 (2017/05/19)
Olefin chemistry, through pericyclic reactions, polymerizations, oxidations, or reductions, has an essential role in the manipulation of organic matter. Despite its importance, olefin synthesis still relies largely on chemistry introduced more than three decades ago, with metathesis being the most recent addition. Here we describe a simple method of accessing olefins with any substitution pattern or geometry from one of the most ubiquitous and variegated building blocks of chemistry: alkyl carboxylic acids. The activating principles used in amide-bond synthesis can therefore be used, with nickel- or iron-based catalysis, to extract carbon dioxide from a carboxylic acid and economically replace it with an organozinc-derived olefin on a molar scale. We prepare more than 60 olefins across a range of substrate classes, and the ability to simplify retrosynthetic analysis is exemplified with the preparation of 16 different natural products across 10 different families.
New catalytic system Cu(OAc)2-2,4-lutidine-ZnCl2 for olefin cyclopropanation with methyl diazoacetate
Gareev,Sultanova,Biglova,Dokichev,Tomilov
experimental part, p. 1784 - 1786 (2011/04/23)
A new efficient catalytic system consisting of Cu(OAc)2, 2,4-lutidine, and ZnCl2 was found for the cyclopropanation of unsaturated compounds with methyl diazoacetate. In the case of conjugated dienes, the process occurs regioselectively at the most alkylated C=C bond.
Novel synthesis of (d,l) trans-chrysanthemic acid involving a β-diketone fragmentation
Krief, Alain,Jeanmart, Stephane
, p. 6167 - 6168 (2007/10/03)
Methyl (d,l) trans-chrysanthemate as well as its cis-diastereoisomer have been prepared from dimethyl dimedone, one of their isomers, in a few steps and with complete control of the relative stereochemistry.
An expeditious enantioselective synthesis of methyl trans-chrysanthemate
Krief, Alain,Dumont, Willy,Baillieul, Diane
, p. 2019 - 2022 (2007/10/03)
Methyl trans-chrysanthemate has been prepared in few steps from isopropylidenediphenylsulfurane and methyl (E)-3-(3,3-dimethyloxiran-2-yl)prop-2-enoate. The latter was obtained from methyl 4-oxobutenoate or 3-methylbut-2-en-1-ol. The Sharpless catalytic epoxidation reaction allows an asymmetric version of this transformation.
Stereoselective synthesis of methyl trans-chrysanthemate and related derivatives
Krief, Alain,Provins, Laurent
, p. 2017 - 2020 (2007/10/03)
γ-hydroxyalkenylstannanes, readily available from α,β- unsaturated esters, α,β-unsaturated aldehydes and tri(n- butyl)stannyllithium, react with boron trifluoride etherate to produce vinyl cyclopropane carboxylic esters. An original highly convergent synthesis of chrysanthemic acid is reported.
Enantioselectivity and cis/trans-Selectivity in Dirhodium(II)-Catalyzed Addition of Diazoacetates to Olefins
Mueller, Paul,Baud, Corine,Ene, Doina,Motallebi, Sharokh,Doyle, Michael P.,et al.
, p. 459 - 470 (2007/10/02)
The RhII-catalyzed carbenoid addition of diazoacetates to olefins was investigated with 4> (1; phox = tetrakis), 4> (2; mepy = tetrakismethyl (2S)-tetrahydro-5-oxopyrrole-2-ca
Stereospecific reaction of an α-sulfonyl carbanion through chelation
Singh, N. P.,Metz, B.,Biellmann, J. F.
, p. 98 - 107 (2007/10/02)
Intramolecular chelation as presented in formula 6 is proposed to explain asymmetric induction of reactions of the carbanion derived from sulfone 10.The designed molecule 10 was obtained from reaction of camphor lithium enolate derived from (+)-camphor (1R,4R bornan-2-one) with sulfur dioxide followed by 3-methyl-2-butenyl bromide to give the keto sulfone 9 which was reduced by LAH to the hydroxysulfone 10.The dianion prepared by action of n-butyllithium gave, with methyl iodide, the mono-methylated product 14 with a diastereomeric excess better than 96percent.The structure of the methylated product was determined by X-ray diffraction.The R configuration at the new asymmetric carbon corresponds to an inversion in the methylation reaction if the species has a chelated structure like 6.With excess of methyl iodide, the C- and O-methylated product 15 was obtained.In the presence of HMPA, the stereoselectivity was lower.The reaction of the carbanion derived from sulfone 10, with methyl 3-methylbut-2-enoate requires the presence of HMPA and leads to chrysanthemic ester 17 with 25percent e.e.
