79791-47-2

Upstream product

• 37674-72-9 6-chloro-chroman-4-one 
• 2627-86-3 (S)-1-phenyl-ethylamine 
• 74-90-8 hydrogen cyanide 
• 79791-45-0 (S)-6-chloro-2,3-dihydro-<(1-phenylethyl)imino>-4H-1-benzopyran 

Downstream Products

• 79791-49-4 (S)-6-chloro-2,3-dihydro-3'-<(S)-1-phenylethyl>spiro<4H-1-benzopyran-4,4'-imidazolidine>-2',5'-dione 

Relevant academic research and scientific papers

Synthesis of Optically Active Spirohydantoins by Asymmetric Induction. Hydantoin Formation from Amino Nitriles and Chlorosulfonyl Isocyanate

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.

Intermediates in the preparation of chiral hydantoins

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

Process for the preparation of chiral hydantoins

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