Conjugation of two functional groups through an unsaturated system was written by Exner, Otto;Bohm, Stanislav. And the article was included in Journal of Physical Organic Chemistry in 2005.Application In Synthesis of (E)-4-Chlorobut-2-enoic acid This article mentions the following:
Energies of 51 1-(E),4-(E)-disubstituted 1,3-butadienes (1), 36 1,4-disubstituted benzenes (2) and 36 (E)-1,2-disubstituted ethenes (3) with dipolar substituents were calculated at the B3LYP/6-311 + G(d,p) level and evaluated in terms of isodesmic reactions expressing the interaction of substituents through the conjugated system. The energy of interaction reaches up to 40 kJ mol-1, it is roughly similar in the three series and most regular in the series 1. While its correlation within the framework of dual substituent parameter anal. lacks phys. meaning, it is possible to sep. the conjugative (resonance) component by subtracting the inductive component with reference to 1,4-disubstituted bicyclo[2.2.2]octanes 4. The conjugative interaction is strongly stabilizing for the combination acceptor-donor and destabilizing for two donors; in these cases it is parallel to changes of geometry as they are predicted by the common resonance formulas. Interaction of two acceptors is weak; in addition, there are groups that cannot be classified either as donors or as acceptors. Therefore, one can construct a scale of the resonance ability of donors in conjugation with an acceptor and vice versa, but it is not possible to express the interaction of two donors or of two acceptors on a unified scale for all substituents. The resonance description is certainly appropriate for the typical examples (interaction of NO2 and NH2) but should not be generalized to all possible structures. In the experiment, the researchers used many compounds, for example, (E)-4-Chlorobut-2-enoic acid (cas: 26340-58-9Application In Synthesis of (E)-4-Chlorobut-2-enoic acid).
(E)-4-Chlorobut-2-enoic acid (cas: 26340-58-9) belongs to organic chlorides. Chlorination modifies the physical properties of hydrocarbons in several ways. These compounds are typically denser than water due to the higher atomic weight of chlorine versus hydrogen. Alkyl chlorides readily react with amines to give substituted amines. Alkyl chlorides are substituted by softer halides such as the iodide in the Finkelstein reaction.Application In Synthesis of (E)-4-Chlorobut-2-enoic acid
Referemce:
Chloride – Wikipedia,
Chlorides – an overview | ScienceDirect Topics