1,7-Bis(tert-butoxycarbonylmethyl)-1,4,7,10-tetraazacyclododecane

Chemical Properties

Pale-Yellow Solid

Uses

Intermediate in the preparation of chelating agents.

Uses

1,7-Bis(tert-butoxycarbonylmethyl)-1,4,7,10-tetraazacyclododecane (DO2A-t-Bu ester) is commonly used intermediates when synthesizing metal complexes for biomedical-related studies.

Uses

The reported synthesis of 1,7-Bis(tert-butoxycarbonylmethyl)-1,4,7,10-tetraazacyclododecane(DO2A-t-Bu ester), is carried out in three steps as depicted in Scheme 1. First, two amines of commercially available cyclen are protected in the trans positions with a slow addition of CBZCl at 0 °C and stirring overnight. Second, t-Bu bromoacetate is reacted with CBZ-protected cyclen, 3, at 60 °C in the presence of diisopropylethylamine (DIEA) to produce macrocycle 4 in 20 h. Finally, hydrogenation for 1 d removes the CBZ groups yielding the desired product.

References

[1] LAUREN E. HOPPER  Matthew J A. Rapid synthesis of 1,7-bis(t-butoxycarbonylmethyl)-1,4,7,10-tetraazacyclododecane (DO2A-t-Bu ester)[J]. Tetrahedron Letters, 2014, 55 40: Pages 5560-5561. DOI:10.1016/j.tetlet.2014.08.026.