Abstract
A new metal-organic framework [Zn2(Cam)2(apyr) ⊃ 2DMF], 4 (apyr = 2-aminopyrazine) has been synthesized by the high temperature equimolar reactions of zinc nitrate with the (+)-camphoric acid (H2Cam) in neat DMF solution. The crystal structure of 4 was determined by X-ray analyses and found to be a porous cubic network composed of linked zinc camphorate “paddlewheel” secondary building units and apyr pillars. The apyr pillars give amino-functionality to the pores. The extended structure of 4 contains guest DMF molecules trapped within the channels. Compound 4 is potentially porous and thermogravimetric analysis is consistent with the initial loss of guest DMF between 75 and 190°C, with the decomposition of the material at 430°C. The material was found to take up racemic alcohols into its pores, however no enantioselectivity was achieved. Reactivity studies of 4 with acetaldehyde show that the amino groups in the pores can be transformed into imine functionalities via post-synthetic covalent modification.
Acknowledgements
The authors gratefully acknowledge the Petroleum Research Fund (41716-AC3) and the National Science Foundation for support (CHE-0443233). They also thank the Center for Environmental Science and Technology at Notre Dame for the use of the Micromass Quatro triple LC quadrupole mass spectrometer and to Professor Paul McGinn (University of Notre Dame) for help with the TGA studies.