The Synthesis of Enantiomers of 6-tert-Butyl-6-methylmorpholine-2,5- dione Using Wang Resin Supported Mukaiyama Reagent
作者:Anna Jakubowska、Joanna Babiuch、Katarzyna Kulig
DOI:10.2174/1570178611310030002
日期:2013.4.1
The synthesis of enantiomers of 6-tert-butyl-6-methylmorpholine-2,5-dione (3) using Wang resin supported 2-
chloro- or 2-bromo- pyridinium triflate is described. The applied methodology could be considered as an interesting alternative
to “classical” one and enables the synthesis of 6-tert-butyl-6-methylmorpholine-2,5-dione with higher yields and
the isolation of product (3) is significantly easier.
Asymmetric Synthesis with 6-tert-Butyl-5-methoxy-6-methyl-3,6-dihydro-2H-1,4-oxazin-2-one as a New Chiral Glycine Equivalent: Preparation of Enantiomerically Pure α-Tertiary and α-Quaternary α-Amino Acids
作者:Claus-Jürgen Koch、Soňa Šimonyiová、Jörg Pabel、Annerose Kärtner、Kurt Polborn、Klaus Theodor Wanner
DOI:10.1002/ejoc.200390179
日期:2003.3
alkylation reactions with other systems with higher oxygen content. From the major diastereomers of both the mono- and the disubstituted derivatives of 2 the corresponding α-aminoacids 33a−c and 34a−d were obtained in high enantiomeric purity by hydrolytic cleavage of the oxazinone ring, accomplished either in two steps with aqueous TFA and aqueous NaOH or in one with either aqueous NaOH or 3 N HBr. Alkylation