Vinyloge Acylverbindungen. XX. Reaktivität und Toxizität arylsubstituierter β‐Chlorvinylketone, β‐Chlorvinylaldehyde und β‐Chlorvinylmethyleniminiumsalze

Abstract

Vinylogous Acyl Compounds. XX. Reactivity and Toxicity of Aryl‐substituted β‐Chlorovinyl Ketones, β‐Chlorovinyl Aldehydes, and β‐Chlorovinyl Methyleniminium Salts Based on kinetic measurements, the nucleophilic replaceability of the chlorine in aromatic β‐chlorovinyl ketones ArCO‐CH  CH‐Cl (1), isomeric β‐chlorovinyl aldehydes OCHCHC(Cl)Ar(2), and corresponding β‐chlorovinyl methyleniminium salts Me2N⊕;CHCHC(Cl)Ar X⊖ (3) is compared and related to toxicological findings. The chemical reactivity of these important synthetic building blocks increases in the order 2<1<3, the acute toxicity (24 h LD50 i. p. in the mouse) shows the graduation 2<3<1. Compounds of type 1 prove to be relatively toxic (LD50 24–42 mg/kg) and display a marked necrotic action after percutaneous absorption, whereas the aldehydes 2 have not only a minor acute toxicity (LD50 158–298 mg/kg) but also a somewhat less marked skin damaging activity. In addition, the LD50 values of selected β‐chlorovinyl carbonyl compounds are compared with those of corresponding halogen‐free compounds as well as of vinylogous carbonamidium salts ArCOCHCHN⊕R3X⊖. The latter, which can be used as synthetic equivalents of 1, differ in both the reduced acute toxicity and missing skin damaging properties.

Critical Casimir forces between defects in the 2D Ising model

“…As pointed out in Ref. [60], in the presence of quenched obstacles, fluid membranes belong to the universality class of the two-dimensional random-field Ising model.…”