20178-20-5Relevant articles and documents
Organocatalytic Mukaiyama Mannich Reactions of 2,5-Bis(trimethylsilyloxy)furan
Laws, Stephen W.,Howard, Sara Y.,Mato, Raquel,Meng, Shuyu,Fettinger, James C.,Shaw, Jared T.
supporting information, p. 5073 - 5077 (2019/07/03)
The organocatalytic synthesis of densely substituted mono- and bis-?-lactams involving the Mukaiyama Mannich addition of 2,5-bis(trimethylsilyloxy)furan to imines is described. Use of a ditoluenesulfonylimide catalyst produces ?-lactams from monoaddition, whereas a more acidic catalyst (triflic acid) produces fused bis-lactams from double addition. Optimized organocatalytic conditions allow for the selective synthesis of either desired core as well as the one-pot, multicomponent assembly of the trisubstituted monolactams from aldehydes, amines, and bis-trimethylsilyloxyfuran. An examination of chiral acids found these organocatalysts to be highly active and diastereoselective in the monoaddition reaction, albeit with no enantioselectivity.
Enantiomers of (2R*,3R*)-1-methyl-5-oxo-2-phenyltetrahydro-1H-pyrrolidine-3-carboxylic acid as novel chiral resolving agents
Piwowarczyk, Katarzyna,Zawadzka, Anna,Roszkowski, Piotr,Szawkalo, Joanna,Leniewski, Andrzej,Maurin, Jan K.,Kranz, Darius,Czarnocki, Zbigniew
, p. 309 - 317 (2008/09/19)
A series of (2R*,3R*)-1-methyl-5-oxo-2-aryltetrahydro-1H-pyrrolidine-3-carboxylic acids were prepared and their structures were proven with X-ray crystallography. Racemic acid 5 has been resolved into enantiomers (2S,3S)-5 and (2R,3R)-5 by the formation of diastereomeric salts with brucine 9 and strychnidine 10, respectively. The ability of these enantiomers to serve as chiral discriminating agents was demonstrated by the chromatographic separation of diastereomeric amides and esters. Also, some preliminary results on the enantioselective reduction of prochiral imines with sodium borohydride modified by (2R,3R)-5 were collected.
