A Pd-catalyzed enantioselective C–H carbonylation by desymmetrization was developed with commercially available L-pyroglutamic acid as chiral ligand. Isoquinolinones were successfully obtained with good yields and high enantioselectivities. Mechanistic studies and DFT calculations provided a reasonable reaction pathway.
[EN] NEW PROCESS FOR THE SYNTHESIS OF TAPENTADOL AND INTERMEDIATES THEREOF<br/>[FR] NOUVEAU PROCÉDÉ POUR LA SYNTHÈSE DE TAPENTADOL ET SES INTERMÉDIAIRES
申请人:ARCHIMICA SRL
公开号:WO2012001571A1
公开(公告)日:2012-01-05
The object of the present invention is a new process for the synthesis of tapentadol, both as free base and in hydrochloride form, which comprises the step of alkylation of the ketone (VII) to yield the compound (VIII), as reported in Diagram 1, with high stereoselectivity due to the presence of the benzyl group as substituent of the amino group. It was surprisingly found that this substitution shifts the keto-enol equilibrium towards the desired enantiomer and amplifies the capacity of the stereocenter present in the compound (VII) to orient the nucleophilic addition of the organometallic compound at the carbonyl towards the desired stereoisomer. This substitution thus allows obtaining a considerable increase of the yields in this step, and consequently allows significantly increasing the overall yield of the entire tapentadol synthesis process. A further object of the present invention is constituted by the tapentadol free base in solid form, obtainable by means of the process of the invention. Still another object of the invention is represented by the crystalline forms I and II of the tapentadol free base. A further object of the present invention is the mixture of the crystalline forms I and II of the tapentadol free base.
CATALYTIC SYSTEMS FOR STEREOSELECTIVE SYNTHESIS OF CHIRAL AMINES BY ENANTIODIVERGENT RADICAL C-H AMINATION
申请人:Trustees of Boston College
公开号:US20200317627A1
公开(公告)日:2020-10-08
In one aspect, the disclosure relates to a mode of asymmetric induction in radical processes based on sequential combination of enantiodifferentiative H-atom abstraction and stereoretentive radical substitution. Also disclosed is an asymmetric system for stereoselective synthesis of strained 5-membered cyclic sulfamides via radical 1,5-C—H amination of sulfamoyl azides. The disclosed metalloradical system can control the degree and sense of asymmetric induction in the catalytic radical C—H amination in a systematic manner. The disclosed system is applicable to a broad scope of substrates with different types of C(sp
3
)-H bonds and exhibits reactivity and selectivity, providing access to both enantiomers of useful 5-membered cyclic sulfamides in a highly enantioenriched form. Also disclosed are catalysts useful in these processes. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present disclosure.
PROCESS FOR THE SYNTHESIS OF TAPENTADOL AND INTERMEDIATES THEREOF
申请人:Motta Giuseppe
公开号:US20130178644A1
公开(公告)日:2013-07-11
The object of the present invention is a new process for the synthesis of tapentadol, both as free base and in hydrochloride form, which comprises the step of alkylation of the ketone (VII) to yield the compound (VIII), as reported in Diagram 1, with high stereoselectivity due to the presence of the benzyl group as substituent of the amino group. It was surprisingly found that this substitution shifts the keto-enol equilibrium towards the desired enantiomer and amplifies the capacity of the stereocenter present in the compound (VII) to orient the nucleophilic addition of the organometallic compound at the carbonyl towards the desired stereoisomer. This substitution thus allows obtaining a considerable increase of the yields in this step, and consequently allows significantly increasing the overall yield of the entire tapentadol synthesis process.
A further object of the present invention is constituted by the tapentadol free base in solid form, obtainable by means of the process of the invention.
Still another object of the invention is represented by the crystalline forms I and II of the tapentadol free base.
A further object of the present invention is the mixture of the crystalline forms I and II of the tapentadol free base.