Phenylglycine methyl ester

The maximum observed free energy difference between two enantiomeric host-guest complexes in which one 1,1 -dinaphthyl element is the only source of chirality in the crown ether is about 0.3 kcal mol-1. Improvement of the free energy difference can be achieved by introduction of two such elements. Unfortunately crown ethers with three 1,1 -dinaphthyl groups did not form complexes with primary ammonium salts (de Jong et al., 1975). The dilocular chiral crown ether [294] forms complexes of different stability with R- and 5-cr-phenylethylammonium hexafluorophosphate. The (J )-J J -[284] complex was the more stable by 0.3 kcal mol-1 at 0°C (EDC value 1.77) (Kyba et al., 1973b). Crown ether [284] also discriminates between the two enantiomers of phenylglycine methyl ester hexafluorophosphate and valine methyl ester... 

Chiral recognition of (f S)-a-phenylethylammonium and ( S)-phenylglycine methyl ester salts by crown ethers in which chiral carbohydrate structure elements are incorporated has been reported by Stoddart et al. (Curtis et al.,... 

Enantiomeric differentiation between (7 S)-cr-phenylethylamine (R = CHj) and (RS)-phenylglycine methyl ester salts (R = COOCH,)°... 

Figure 10.4 Acylation of (S)-phenylglycine methyl ester in the presence of penicillin G acylase.

PGA D-Phenylglycine amide PGME D-Phenylglycine methyl ester PhAc Phenylacetic acid... 

U.yUNSATURATED KETONES Bis-(l,5-cyclooctadiene)nickel(0). Dimethyl-(phenylthio)aluminum. a-Phenylglycine methyl ester. Phcnylselcnoacetaldchydc. Zinc-Silver couple. 

Lou, W.-Y., Zong, M.-H., Liu, Y.-Y., and Wang, J.-F. 2006. Efficient enantioselective hydrolysis of D,L-phenylglycine methyl ester catalyzed by immobilized Candida antarctica lipase B in ionic liquid containing systems. Journal of Biotechnology, 125 64—74. 

Sasaki, K., Satake, M., and Yasumoto, T. 1997. Identification of the absolute configuration of pectenotoxin-6, a polyether macrolide compound, by NMR spectroscopic method using a chiral anisotropic reagent, phenylglycine methyl ester. 

Thus, the mixture of a solution of roc-phenylglycine methyl ester in CHjClj and a yellow solution of 3-hexadecanoyl-(4/ )-methoxycarbonyl-l,3-thiazolidine-2-thione (14a) in the same solvent was stirred at room temperature in nitrogen until the original yellow color of the medium vanished. A usual workup gave an optically active amide 16 in 93.7% yield [enantiomeric excess percent (ee%) = 64.4 (S excess [ ]d +50.35°) based on the pure amide 16] (82TL201). The N-acylation of (4R)-MCTT (1) was carried out by its treatment with hexadecanoyl chloride in the presence of EtjN in tetrahydrofuran (THF) or by treatment of the thallium salt with hexadecanoyl chloride in THF. 

The aqueous layer on usual workup gave optically active phenylglycine methyl ester hydrochloride in 83.4% yield [ee% = 45.9 (1 excess [a]D° -60.59°) based on pure (/ )-phenylglycine methyl ester hydrochloride [a] ° -132.13°] (Scheme 3). 

Sasaki, K., Onodera, H., and Yasumoto, T. (1998) Applicability of the phenylglycine methyl ester to the establishment of the absolute configuration of dinophysistoxin-1, a polyether toxins responsible for diarhet-tic shellfish poisoning. Enantiomer, 3, 59-63. 

Thus, the mixture of a solution of rac-phenylglycine methyl ester in CHjClj and a yellow solution of 3-hexadecanoyl-(4R)-methoxycarbonyl-... 

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