21511-55-7Relevant articles and documents
Converging and Diverging Synthetic Strategies to Tetradentate (N,N')-Diaminomethyl,(P,P')-Ferrocenyl Ligands: Influence of tert-Butyl Groups on Ferrocene Backbone Conformation
Allouch, Fatima,Dwadnia, Nejib,Vologdin, Nikolay V.,Svyaschenko, Yurii V.,Cattey, Hélène,Penouilh, Marie-José,Roger, Julien,Naoufal, Daoud,Ben Salem, Ridha,Pirio, Nadine,Hierso, Jean-Cyrille
, p. 5015 - 5028 (2015)
Hexasubstituted hybrid tetradentate (N,N',P,P')-ferrocenes bearing phosphino and aminomethyl groups, plus hindering tert-butyl moieties, were synthesized by using two different strategies: a "diverging" synthesis involving successive functionalization of preformed di-tert-butylated ferrocene and a "converging" assembly of the species from appropriately substituted cyclopentadienyl rings. While the new cyclopentadienyl salts formed are of interest, their assembly with iron dichloride used as a "converging" way to produce tetradentate ferrocene ligands presented several drawbacks. Conversely, the synthesis of new tert-butylated (aminomethyl)ferrocene derivatives was found convenient to further form (N,N')-aminomethyl,(P,P')-tert-butylated-ferrocenyl diphosphines by N-directed ortho-metalation. The novel N2-didentate and N2P2-tetradentate tert-butylated ferrocene compounds were all synthesized in good to high yields (48-96%) and tolerated aryl, alkyl, and heteroaryl phosphino groups as substituents on nitrogen and phosphorus atoms. They were characterized by X-ray diffraction and multinuclear NMR (1H, 13C, 31P, 15N). We observed the conformation control provided to rac-(N,N')-diaminomethyl-(P,P')-tert-butylated-ferrocenyldiphosphines with in particular the systematic near-eclipsed conformation of aminomethyl groups. This conformation is at the origin of the unexpected formation at RT of a zwitterionic cyclopalladate from an (aminomethyl)ferrocene derivative, arising from intramolecular Cp-proton transfer to the proximate free amino group by simple C-H activation reaction in the presence of palladium dichloride.
Practical Synthetic Method for the Preparation of Pyrone Diesters: An Efficient Synthetic Route for the Synthesis of Dolutegravir Sodium
Yasukata, Tatsuro,Masui, Moriyasu,Ikarashi, Fumiya,Okamoto, Kazuya,Kurita, Takanori,Nagai, Masahiko,Sugata, Yoshihide,Miyake, Naoki,Hara, Shinichiro,Adachi, You,Sumino, Yukihito
, p. 565 - 570 (2019/03/26)
A highly efficient and practical synthetic method for the preparation of pyrone diesters was established. The pyrone diester 3c can be prepared from readily available starting materials on a multihundred gram scale. The pyrone diester 3c can easily be converted to dolutegravir sodium (1). The synthetic route demonstrated herein provides an efficient and atom-economical synthetic method for preparing this potent anti-HIV agent.
Preparation method of enamine compounds
-
Paragraph 0037-0041, (2019/10/15)
The invention relates to the field of preparation of enamine compounds, and discloses a preparation method of the enamine compounds shown in a formula (I). The method comprises the step of enabling acompound as shown in a formula (II) to react with a compound as shown in a formula (III) in presence of an alkaline substance; the formula (I), the formula (II) and formula (III) are described in thedescription, wherein R1 is hydrogen or alkyl groups of C1-C4; R2, R3 and R4 are the same or different and are independently the alkyl groups of C1-C4; n is 0 or 1. The preparation method is simpler and more convenient in process, easy in obtaining of raw materials, lower in cost, and high in reaction conversion rate and selectivity.
