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, CH 3 CH=CHC(O)NHOH 5 contains centrosymmetrically-related pairs of acid molecules, with a short contact of 3.36 Å between the a-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 R 4 2 ð10Þ and R 4 4 ð18Þ ring systems. Facile preparation of metal salts of the acid is reported, as well as discussion of the effect of heating and 60 Co c-irradiation of the materials.