79791-49-4Relevant academic research and scientific papers
Intermediates in the preparation of chiral hydantoins
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, (2008/06/13)
A novel process for the synthesis of chiral hydantoins of the structure STR1 wherein X is fluoro or chloro, from the corresponding 6-halo-4-chromanone of the structure STR2 is described. The compounds I are valuable in the treatment of certain chronic com
Synthesis of Optically Active Spirohydantoins by Asymmetric Induction. Hydantoin Formation from Amino Nitriles and Chlorosulfonyl Isocyanate
Sarges, Reinhard,Howard, Harry R.,Kelbaugh, Paul R.
, p. 4081 - 4085 (2007/10/02)
Conversion of 6-chloro- or 6-fluoro-2,3-dihydro-4H-1-benzopyran-4-one with optically active (S)-α-methylbenzylamine in the presence of TiCl4 to the ketimine followed by treatment in EtOH with HCN gas gives excellent yields of crystalline, enantiomerically pure (4S)-4-cyano-2,3-dihydro-6-chloro(or 6-fluoro)-4--4H-1-benzopyran.These sterically hindered amino nitriles react smoothly with chlorosulfonyl isocyanate to give, after hydrolysis, the hydantoins (4S)-2,3-dihydro-6-chloro(or 6-fluoro)-3'-spiro-2',5'-dione.The α-methylbenzyl groups can be removed by aqueous HBr/acetic acid to give the unprotected spirohydantoins.
Process for the preparation of chiral hydantoins
-
, (2008/06/13)
A novel process for the synthesis of chiral hydantoins of the structure STR1 wherein X is fluoro or chloro, from the corresponding 6-halo-4-chromanone of the structure STR2 is described. The compounds I are valuable in the treatment of certain chronic com
