反应详情

The procedure used by Welch, Dolfini and Giarrusso in U.S. Pat. 3,720,665 (Example 1) to make D-2-amino-2-(1,4-cyclohexadienyl)acetic acid was adapted. A solution of 830 ml. of distilled liquid ammonia was dried with 40 mg. of lithium under an argon atmosphere. To this stirred solution was added 11.0 g. (0.07 mole) of 2 -aminomethylphenylacetic acid and 340 ml. of tert. butyl alcohol. A total of 1.6 g. (0.225 mole) of lithium was added to the vigorously stirred solution over a period of 2 hours. The grey mixture was then treated with 35 g. (0.215 mole) of triethylamine (TEA) hydrochloride and stirred overnight at room temperature for 18 hours. The tert. butyl alcohol was removed at 40° (15 mm.) to yield a white residue which was dried in vacuo over P2O5 overnight. The solid was dissolved in 30 ml. of 1:1 methanol-water and added with stirring to 3.5 l. of 1:1 chloroform-acetone at 5°. the mixture was stirred for 20 min. and the amino acid α-(2-aminomethyl-1,4-cyclohexadienyl)acetic acid, was collected and dried for 16 hours in vacuo over P2O5 to yield 6.3 g. (58%) of white crystals, m.p. 190° decomp. The IR and NMR spectra were consistent for the structure.

1. dry with materialof distilled liquid ammonia was dried with 40 mg
2. additionTo this stirred solution was added 11.0 g
3. additionThe grey mixture was then treated with 35 g
4. customThe tert. butyl alcohol was removed at 40° (15 mm.)
5. customto yield a white residue which
6. dry with materialwas dried in vacuo over P2O5 overnight
7. dissolutionThe solid was dissolved in 30 ml
8. additionof 1:1 methanol-water and added
9. customat 5°
10. stirringthe mixture was stirred for 20 min.
11. customthe amino acid α-(2-aminomethyl-1,4-cyclohexadienyl)acetic acid, was collected
12. dry with materialdried for 16 hours in vacuo over P2O5
13. customto yield 6.3 g