Crystal and Molecular Structure of Crotonohydroxamic Acid, and a Preliminary Investigation of the Solid-State Reactivity of the Acid and Its Salts

ABSTRACT

The crystal structure of crotonohydroxamic acid, CH₃CH˭CHC(O)NHOH 5 contains centrosymmetrically-related pairs of acid molecules, with a short contact of 3.36 Å between the α-carbon atoms. The observed arrangement provides excellent alignment for a solid-state ene reaction, but, apparently, the threshold temperature for such a process cannot be realized. The hydrogen bonding patterns observed include C(5) chains and both and ring systems. Facile preparation of metal salts of the acid is reported, as well as discussion of the effect of heating and ⁶⁰Co γ-irradiation of the materials.

Keywords:

• crystal structure
• crotonohydroxamic acid
• solid state reaction
• hydrogen bonding
• γ-irradiation

Acknowledgments

We thank the National Science Foundation (Grant DMR-0089257) for partial support of this research, and Professor B. B. Snider for helpful discussions.

Notes

^a R = ∑||F _o | − |F _c ||/∑|F _o |

^b

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