133545-89-8

Basic information

• Product Name: [(1R)-2-(benzyloxy)-2-oxo-1-phenylethyl]ammonium 4-methyl-1-benzensulfonate
• Synonyms: [(1R)-2-(benzyloxy)-2-oxo-1-phenylethyl]ammonium 4-methyl-1-benzensulfonate
• CAS NO: 133545-89-8
• Molecular Weight: 413.494
• Mol File: 133545-89-8.mol
• Article Data: 3

Chemical Properties

• CAS DataBase Reference: [(1R)-2-(benzyloxy)-2-oxo-1-phenylethyl]ammonium 4-methyl-1-benzensulfonate(CAS DataBase Reference)
• NIST Chemistry Reference: [(1R)-2-(benzyloxy)-2-oxo-1-phenylethyl]ammonium 4-methyl-1-benzensulfonate(133545-89-8)
• EPA Substance Registry System: [(1R)-2-(benzyloxy)-2-oxo-1-phenylethyl]ammonium 4-methyl-1-benzensulfonate(133545-89-8)

Safety Data

• Hazardous Substances Data: 133545-89-8(Hazardous Substances Data)

Upstream product

• 104-15-4 toluene-4-sulfonic acid 
• 2835-06-5 phenylglycin 
• 100-51-6 benzyl alcohol 
• 151123-29-4 Methyl N-(diphenylmethylene)-D-phenylglycinate 
• 19883-41-1 D-phenylglycine methyl ester hydrochloride 
• 875-74-1 (R)-phenylglycine 
• 138892-12-3 (R)-(Benzhydrylidene-amino)-phenyl-acetic acid benzyl ester 

Downstream Products

• 875-74-1 (R)-phenylglycine 
• 171290-64-5 (R,R)-N,N'-oxalylbis(phenylglycine) 
• 54384-11-1 N-(4-Methoxycarbonylbutyryl)phenylglycin 
• 1372151-00-2 C₁₈H₁₉NO₂ 
• 858884-54-5 (R)-{(2R,3R)-3-[((R)-Benzyloxycarbonyl-phenyl-methyl)-carbamoyl]-2,3-dihydroxy-propionylamino}-phenyl-acetic acid benzyl ester 
• 260051-49-8 (R)-((R)-2-Benzyloxycarbonylamino-2-phenyl-acetylamino)-phenyl-acetic acid benzyl ester 
• 266681-39-4 (R,R)-O,O'-dibenzyl N,N'-oxalylbis(phenylglycine) 
• 851679-73-7 (S)-[((S)-Methoxycarbonyl-phenyl-methyl)-aminooxalyl]-amino)-phenyl-acetic acid methyl ester 
• 266681-40-7 (R)-[((S)-Methoxycarbonyl-phenyl-methyl)-aminooxalyl]-amino)-phenyl-acetic acid benzyl ester 

Relevant articles and documents

One-step preparation of enantiopure l- or d-amino acid benzyl esters avoiding the use of banned solvents

The enantiomers of amino acid benzyl esters are very important synthetic intermediates. Many of them are currently prepared by treatment with benzyl alcohol and p-toluenesulfonic acid in refluxing benzene or carbon tetrachloride, to azeotropically remove water, and then precipitated as tosylate salt by adding diethyl ether. Here, we report a very efficient preparation of eight l- or d-amino acid benzyl esters (Ala, Phe, Tyr, Phg, Val, Leu, Lys, Ser), in which these highly hazardous solvents are dismissed using cyclohexane as a water azeotroping solvent and ethyl acetate to precipitate the tosylate salt. With some work-up modifications and lower yield, the procedure can be applied also to methionine. Chiral HPLC analysis shows that all the benzyl esters, including the highly racemizable ones such as those of phenylglycine, tyrosine and methionine, are formed enantiomerically pure under these new reaction conditions thus validating the solvents replacement. Contrariwise, toluene cannot be used in place of benzene or carbon tetrachloride because leading to partially or totally racemized amino acid benzyl esters depending on the polar effect of the amino acid α-side chain as expressed by Taft’s substituent constant (σ*).

Oxygen alkylation of Schiff base derivatives of amino acids

Higher imine esters 1a-h and 7a-b of amino acids and dipeptides are prepared in 68-91% yield by saponification of the benzophenone Schiff base methyl esters 3a-d and 6 using phase-transfer techniques followed by O-alkylation with an alkyl halide. The procedure occurs with retention of configuration at the α-carbon except with phenylglycine derivatives.