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Polymorphic di-2-pyridyl ketone 4-nitrophenylhydrazone (dpknph): the structure of beta-dpknph
Mohammed Bakir1, Rebecca R Conry, Orville Green
1Department of Chemistry, University of the West Indies, Mona Campus, Kingston 7, Jamaica. mohammed.bakir@uwimona.edu.jm
Abstract:
A new polymorph of di-2-pyridyl ketone 4-nitrophenylhydrazone [alternative name: N-(dipyridin-2-ylmethylene)-N'-(4-nitrophenyl)hydrazine], C17H13N5O2, isolated from the filtrate of a sonicated acetonitrile solution of dpknph and CdCl2, was found to crystallize in the monoclinic space group P21/c, in contrast to the known form which crystallizes in P21/n. The non-coplanar molecules pack in parallel stacks without any intermolecular hydrogen-bonding interactions. This packing pattern contrasts with the interlocked interdigitated packing seen in the previously known polymorph.
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