1-phenylbutane-1,3-diol

Conditions: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: First, 5.0 g (31 mmol) of L-glutamic acid-γ-methyl ester was suspended in 15 mL of methanol. To this, 5.6 g (34 mmol) of 1-phenyl-1,3-butanediol and 3.1 g (31 mmol) of triethylamine were added. The mixture was heated at 60° C. for 2 hours. Subsequently, 20 g (310 mmol) of 70% ethylamine was added to the mixture and the same procedure as in Example 1 was performed to obtain 4.7 g of theanine (yield: 87%). The obtained theanine had the same purity as high as in Example 1.