104057-70-7

Upstream product

• 98-88-4 benzoyl chloride 
• 630-19-3 pivalaldehyde 
• 63-68-3 L-methionine 

Downstream Products

• 161007-05-2 N-[(S)-3-(2-Methylsulfanyl-ethyl)-2-oxo-pyrrolidin-3-yl]-benzamide 
• 161007-04-1 [(2S,4S)-3-Benzoyl-2-tert-butyl-4-(2-methylsulfanyl-ethyl)-5-oxo-oxazolidin-4-yl]-acetonitrile 
• 104057-78-5 (2S,4S)-3-benzoyl-2-(tert-butyl)-4-methyl-4-(3'-thiabutyl)-1,3-oxazolidin-5-one 

Relevant academic research and scientific papers

Addition of Chiral Glycine, Methionine, and Vinylglycine enolate Derivatives to Aldehydes and Ketones in the Preparation of Enantiomerically Pure α-Amino-β-hydroxy Acids

Chiral enolates of imidazolidinones and oxazolidinones from the title amino acids react with carbonyl compounds to afford the corresponding alcohols in excellent yields (see Scheme 5).Furthermore, the addition to aldehydes proceeds with high diastereoselectivity to give, after acid hydrolysis, threo-α-amino-β-hydroxy acids of high enantiomeric purity.Some of the threo-α-amino-β-hydroxy acids prepared in this work are the proteinogenic (S)-threonine (26), the naturally occuring (S)-3-phenylserine (28), and (S)-3-hydroxyleucine (27) as well as the unnatural (S)-4,4,4-rtifluorothreonine (30) and (S)-3-(4-pyridyl)serine (31).The N-methylamide of (2S,3R,4R,6E)-3-hydroxy-4-methyl-2-(methylamino)-6-octenoic acid (32), the uniqe amino acid in the immunosuppressive cyclosporine, was prepared by the new method.This report presents also information suggesting that both steric and stereoelectronic effects are responsible for the good stereoselectivities observed.

N,O-Acetals from Pivalaldehyde and Amino Acids for the α-Alkylation with Self-Reproduction of the Center of Chirality. Enolates of 3-Benzoyl-2-(tert-butyl)-1,3-oxazolidin-5-ones

The sodium salt of (S)-alanine, (S)-phenylalanine, (S)-valine, and (S)-methionine are condensed with pivalaldehyde to imines 5.Cyclization by treatment with benzoyl chloride in cold CH2Cl2 gives mainly (4:1 to > 99:1) the (2S,4S)-4-alkyl-3-benzoyl-2-(tert-butyl)-1,3-oxazolidin-5-ones (6; cis-configuration) in high yields (85-95 percent).The oxazolidinones 6 and 7 are deprotonated with lithium diethylamide (LDEA) in tetrahydrofuran (THF) and alkylated (MeI, benzyl bromide) or hydroxyalkylated (benzaldehyde) to 4,4-disubstituted oxazolidinones 9 and 10, respectively, with high diastereoselectivity (9:1 to 50:1; relative topicity ul).Hydrolysis of three of the oxazolidinones to amino acids of known configuration and optical purity indicates that little if any racemization occurs in the process.