[13139-12-3]  · C9H13NO5  · N-(t-Butoxycarbonyloxy)succinimide  · (MW 215.21)

(reagent for the protection of amino groups, including amino acids2)

Alternate Name: Boc-OSu.

Physical Data: mp 98-100 °C.1

Solubility: sol ether, ethyl acetate, acetone; insol water, petroleum ether.

Form Supplied in: white solid, widely available.

Handling, Storage, and Precautions: stable under normal storage conditions. No known toxicity.

Protection of Amino Compounds.

N-(t-Butoxycarbonyloxy)succinimide (Boc-OSu) has been developed to supplement the unstable t-Butyl Chloroformate for the protection of amino compounds and especially of amino acids. The reagent is a stable compound easily prepared from t-butanol and N-oxysuccinimide chloroformate1 and has been used for the protection of various compounds including amino acids, peptides,2 proteins,3,4 and amino saccharides.5 N-Oxysuccinimide carbonates have been shown to give very pure N-protected amino acids with a particularly low content of dipeptide byproduct.6 It is also noteworthy that both the Boc and the OSu groups can be introduced into amino acids almost simultaneously in a one-pot synthesis of Boc-protected N-oxysuccinimide active esters of amino acids (eq 1).7

Attempts to protect a-hydrazino acids regioselectively led to almost no discrimination between N-a and N-b protection, compared to the very good regioselectivity observed with benzyloxycarbonyloxysuccinimide (eq 2).8

1. Gross, H.; Bilk, L. LA 1969, 725, 212.
2. Hojo, H.; Aimoto, S. BCJ 1992, 65, 3055.
3. Losse, G.; Naumann, W.; Raddatz, H. ZC 1983, 23, 22.
4. Grau, U. E. Ger. Patent 3 326 472 (CA 1985, 103, 88 221).
5. Matsushima, H.; Mori, Y. Jpn. Patent 53 079 843 (CA 1978, 90, 23 603).
6. Laptsanis, L.; Milias, G.; Froussios, K.; Kolovos, M. S 1983, 671.
7. Frankel, M.; Ladkany, D.; Gilon, C.; Wolman, Y. TL 1966, 4765.
8. Lecoq, A.; Marraud, A.; Aubry, A. TL 1991, 32, 2765.

G. Sennyey

SNPE, Vert-le-Petit, France

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