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Updated: Mar 29, 2026

Microwave-assisted Intramolecular Dehydrogenative Diels-Alder Reactions for the Synthesis of Functionalized Naphthalenes/Solvatochromic Dyes
Published on: April 1, 2013
Crystal structure of (E)-2-(4-chloro-benzyl-idene)-3,4-di-hydro-naphthalen-1(2H)-one: a second monoclinic polymorph
Muhammad Haroon1, Tashfeen Akhtar1, Muhammad Nawaz Tahir2
1Department of Chemistry, Mirpur University of Science and Technology (MUST), Mirpur, Azad Jammu and Kashmir, Pakistan.
Abstract:
The title compound, C17H13ClO, is the second monoclinic polymorph to crystallize in the space group P21/c. The first polymorph crystallized with two independent mol-ecules in the asymmetric unit [Bolognesi et al. (1975 ▸). Acta Cryst. A31, S119; Z' = 2; no atomic coordinates available], whereas the title compound has Z' = 1. In the title polymorph, the dihedral angle between the plane of the benzene ring of the tetra-lone moiety and that of the 4-chloro-benzyl ring is 52.21 (11)°. The cyclo-hex-2-en-1-one ring of the tetra-lone moiety has a screw-boat conformation. In the crystal, mol-ecules are liked by pairs of C-H⋯π inter-actions forming inversion dimers. There are no other significant inter-molecular inter-actions present.
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