77124-15-3Relevant academic research and scientific papers
A new chemoenzymatic synthesis of the chiral Key intermediate of the antiepileptic Brivaracetam
Ciceri, Samuele,Grisenti, Paride,Elahi, Shahrzad Reza,Ferraboschi, Patrizia
, (2018/09/10)
Brivaracetam is a new anticonvulsant compound, recently approved as an antiepileptic drug. This drug substance presents a 4-substituted pyrrolidone structure: the (4R)-configuration of the stereocenter present on the heterocyclic ring is the main target of the synthesis. The described method allows to prepare the suitable optically pure 2-substituted primary alcohol by means of a Pseudomonas fluorescens lipase-catalyzed transesterification. The obtained (2R)-alcohol was easily transformed into the (3R)-3-propylbutyrolactone, an advanced intermediate of brivaracetam. The described synthetic pathway is completed with the chromatographic methods and the NMR analyses necessary to establish the chemical and the optical purity of the intermediates and of the final lactone.
A study of the reaction of n-BuLi with Ti(Oi-Pr)4 as a method to generate titanacyclopropane and titanacyclopropene species
Rassadin, Valentin A.,Six, Yvan
, p. 787 - 794 (2014/01/23)
The use of the combination of reagents Ti(Oi-Pr)4/n-BuLi, introduced by the group of J.J. Eisch in 2001, has only found a few applications so far, with sometimes conflicting observations. This article describes a study aimed at clarifying the nature, the stability and the reactivity of the active organometallic species involved. Reactions with CO2 and other trapping reagents reveal that it is generated within a few minutes at 0 C in THF, where it can be considered to be stable for 30 min. Most of our results are consistent with the expected titanacyclopropane nature of this reagent but some observations suggest that the chemistry at play may be more complicated.
Highly enantioselective construction of the α-chiral center of amides via iridium-catalyzed hydrogenation of α,β-unsaturated amides
Lu, Wei-Jing,Hou, Xue-Long
supporting information; experimental part, p. 1224 - 1228 (2009/12/06)
The chiral center at the a-position of amides is installed in excellent enantioselectivity via the iridium-catalyzed asymmetric hydrogenation of αβ-unsaturated amides under mild conditions. Even aliphatic amides are suitable substrates. The presence of a
Titanium-mediated carboxylation of alkynes with carbon dioxide
Six, Yvan
, p. 1157 - 1171 (2007/10/03)
The regioselective carboxylation of nonactivated internal alkynes can be performed with carbon dioxide under atmospheric pressure using a simple procedure based on the chemistry of Sato-type diisopropyloxytitanacyclopropenes. Various polysubstituted vinylcarboxylic acids and butenolides can be prepared in this way. In addition, this paper describes an experimental protocol for the preparation of solutions of (η2-cyclopentene)diisopropyloxytitanium. This complex also reacts with carbon dioxide, and mediates pinacol coupling of acetophenone. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003.
The reaction of dialkoxytitanacyclopropanes and dialkoxytitanacyclopropenes with carbon dioxide
Six, Yvan
, p. 1159 - 1160 (2007/10/03)
Dialkoxytitanacyclopropanes and dialkoxytitanacyclopropenes react with one molecule of carbon dioxide to afford diversely substituted carboxylic acids after hydrolysis.
α-LITHIOALKYLPHOSPHONATES AS FUNCTIONAL GROUP CARRIERS. PART II. A DIRECT (E)-CINNAMIC AND 2-ALKYL-CINNAMIC ACIDS SYNTHESIS.
Teulade, Marie-Paule,Savignac, Philippe,About-Jaudet, Elie,Collignon, Nooel
, p. 71 - 82 (2007/10/02)
Sequential treatment of α-lithioalkylphosphonates with tert-butyl fluoroformate or di-tert-butyl dicarbonate and an aromatic aldehyde gives tert-butyl acrylic esters convertible into acrylic acids by protolysis with trifluoroacetic acid.
A Simple and Efficient Route to 2-Alkyl-2-alkenoic Acids and 2-Phenyl-2-Alkenoic Acids by the Horner Synthesis. Application to the Steroselective Synthesis of the Pheromone Manicone
Coutrot, Philippe,Ghribi, Abdellaziz
, p. 790 - 792 (2007/10/02)
A general synthesis of α-branched α,β-unsaturated carboxylic acids is described.A Horner reaction of 2-diethoxyphosphorylalkanoic acid dianions (lithium α-lithiocarboxylates) with carbonyl compounds is used.The reaction is applied to the stereoselective synthesis of Manicone.
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.
