N-(tert-butoxycarbonyl)glycine → Boc-Gly-Leu-Ala-OBzl

Participants

Reaction Steps

Boc-Gly-Leu-Ala-OBzl was prepared by coupling Boc-Gly-OH (5.70 g, 32.6 mmoles) to H-Leu-Ala-OBzl using the mixed anhydride procedure described in Example 2. The product (13.8 g) was obtained as an amorphous solid. Boc-Gly-Leu-Ala-OBzl was deblocked with trifluoroacetic acid by the procedure described for the preparation of H-Leu-Ala-OBzl except that the trifluoroacetate salt was soluble in ether. The preparation was dissolved in ethyl acetate and treated with anhydrous hydrogen chloride. The resulting product was precipitated by the addition of ether to yield 7.7 g of H-Gly-Leu-Ala-OBzl .HCl in a first crop.

Provenance & Evidence