Taming Ambident Triazole Anions: Regioselective Ion Pairing Catalyzes Direct N-Alkylation with Atypical Regioselectivity
作者:Harvey J. A. Dale、George R. Hodges、Guy C. Lloyd-Jones
DOI:10.1021/jacs.9b02786
日期:2019.5.1
of an organocatalytic methodology for ambident control in the direct N-alkylation of unsubstituted triazole anions. Amidinium and guanidinium receptors are shown to act as strongly coordinating phase-transfer organocatalysts, shuttling triazolate anions into solution. The intimate ion pairs formed in solution retain the reactivity of liberated triazole anions but, by virtue of highly regioselective
Are Oxazolidinones Really Unproductive, Parasitic Species in Proline Catalysis? – Thoughts and Experiments Pointing to an Alternative View
作者:Dieter Seebach、Albert K. Beck、D. Michael Badine、Michael Limbach、Albert Eschenmoser、Adi M. Treasurywala、Reinhard Hobi、Walter Prikoszovich、Bernard Linder
DOI:10.1002/hlca.200790050
日期:2007.3
and reactions of the oxazolidinone derived from proline and cyclohexanone. This oxazolidinone reacts (THF, room temperature) with the electrophiles β-nitrostyrene and chloral (=trichloroacetaldehyde), to give the Michael and aldol adduct, respectively, after aqueous workup (Scheme 5). The reactions occur even at −75° when catalyzed with bases such as 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) or EtN(i-Pr)2
GLYCOSYLATED VALPROIC ACID ANALOGS AND USES THEREOF
申请人:HEYMAN Norman S.
公开号:US20130029924A1
公开(公告)日:2013-01-31
Glycosylated valproic acid and its analogs are provided. In some embodiments, the glycosylated valproic acid and its analogs have improved solubility and are ideal for drug delivery to treat a variety of diseases.
Starting from (+)- or (−)-camphor, the antipodal alcohols 14 and 18, respectively, have been prepared; the corresponding acrylates 15 and 19 underwent TiCl2(i-PrO)2-mediated Diels-Alder additions to cyclopentadiene to give adducts 20a and 22a respectively, with 95 % endo- and 99.2% πpH-face selectivities. Adduct 22a was converted to enantiomerically pure norbornenone 26. Addition of 1,3-butadiene to
The present invention is related to a process for preparing safinamide and salts thereof, preferably safinamide methanesulfonate, with high yields and high enantiomeric and chemical purity without the need of using highly pure intermediates. The process of the present invention is suitable for the production of safinamide and its salts, preferably safinamide methanesulfonate, at industrial scale.