[EN] NOVEL PROCESS FOR THE PREPARATION OF SPIROHETEROCYCLIC PYRROLIDINE DIONES [FR] NOUVEAU PROCÉDÉ DE PRÉPARATION DE PYRROLIDINE DIONES SPIROHÉTÉROCYCLIQUES
PROCESS FOR PREPARING 2,6-DIALKYLPHENYLACETIC ACIDS
申请人:Bayer Aktiengesellschaft
公开号:US20210403406A1
公开(公告)日:2021-12-30
The invention relates to a multi-stage process for preparing 2,6-dialkylphenylacetic acids of the general formula (I) by reacting 2,6-dialkylbromobenzenes with (1) magnesium, (2) a formamide, (3) an acid, (4) hydrogenation of the benzaldehyde obtained, (5) activation of the benzyl alcohol obtained, (6) cyanation of the activated benzyl alcohol and (7) hydrolysis of the nitrile obtained.
PROCESS FOR PREPARING ESTERS OF N-ACYLATED AMINO ACIDS WITH ACID-LABILE KETO PROTECTIVE GROUP FUNCTIONS
申请人:Bayer Aktiengesellschaft
公开号:US20210139450A1
公开(公告)日:2021-05-13
The present invention relates to a novel process for the esterification of N-acylated amino acids which contain an acid-labile keto protective group under alkaline conditions without using a polar aprotic solvent, in which the N-acylated amino acid with acid-labile keto protective group prepared in situ is esterified using an alkyl halide or a mono- or dialkyl ester of sulfuric acid.
The invention relates to a process for preparing substituted 2-arylethanols of the formula (I) by reacting Grignard compounds of the formula (II) in the presence of a copper compound with ethylene oxide. Moreover, the invention relates to novel substituted 2-arylethanols of the formula (I).