TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Process: In the process: addition of tert-butyl amine is carried out at room temperature; and reaction is carried out in presence of coupling agent consisting of N,N'-diethylcarbodiimide, N,N'-dipropylcarbodiimide N,N'-diisopropylcarbodiimide, N,N'-dicyclohexylcarbodiimide, N-ethyl-N1-(3-(dimethylamino)propyl)carbodiimide or N,N'-carbonyldiimidazole. Preferred Components: The salt is methylamine, ethylamine, isopropylamine, tert-butylamine (preferred), tris(hydroxymethyl)methylamine, cyclohexyamine, benzylamine, 4-methoxybenzylamine ethanolamine, diethanolamine, piperazine or tromethamine. The organic solvent is tetrahydrofuran, 1,4-dioxane methylene chloride, ethylene chloride, cyclohexane, toluene, ethyl acetate, diethyl ether, isopropyl ether or methyl tert-butyl ether. The azodicarboxylate and phosphine are present at 1-5 moles/mole. ACTIVITY - Antidiabetic.    MECHANISM OF ACTION - Glucagon like peptide-1 modulator; Dipeptidyl peptidase-4 inhibitor.    EXAMPLE - 5-(1-hydroxy-2-(2,4,5-trifluorophenyl)ethylidene)-2,2-dimethyl-1,3-dioxane-4,6-dione compound (X) (400 g) was refluxed with methanol (2000 ml), followed by sodium bicarbonate and worked up to give 3-oxo-4-(2,4,5-trifluoro-phenyl)-butyric acid methyl ester compound (IX), which was further converted into 3(S)-2,4,5-trifluoro-3-hydroxy benzenebutanoic acid methyl ester compound (VIII) using asymmetric hydrogenation by charging methanolic solution of (IX) (1400 ml) into hydrogenation reactor (1000 l), followed by the addition of (S)-2,2'-bis(diphenylphosphino)-1,1'-binaphthyl ((S)-BINAP) ruthenium(III) chloride-triethylamine complex (prepared by adding (S)-BINAP (1.81 g), 1,5-cyclooctadiene ruthenium chloride (0.7 g) and triethylamine (30.05 g) into methanolic reflux (1400 ml) for 20 hours). Asymmetric hydrogenation was carried out with hydrogen pressure (6-6.5 kg/cm) at 80-85 degrees C, and worked up to give 3(S)-2,4,5-trifluoro-3-hydroxybenzenebutanoic acid compound.