Koskinen , A M P , Brunner , M , Straub , T , Saarenketo , P & Rissanen , K 2004 , ' Highly Diastereoselective Methylation of Five-Ring N,O-Acetals ' LETTERS IN ORGANIC CHEMISTRY , vol 1 , no. 3 , pp. 268-270 .
Abstract:
Highly diastereoselective methylation of (2S,4S)- and (2R,4S)-3-tert-butyl 4-methyl 2-tertbutyloxazolidine-3,4-dicarboxylate (1a/b) is reported. The relative and absolute configuration of the methylated products was assigned by NOESY and confirmed by a crystal structure of 1a.