title: Unexpectedly Stable (Chlorocarbonyl)(N-ethoxycarbonylcarbamoyl)disulfane, and Related Compounds That Model the Zumach-Weiss-Kühle (ZWK) Reaction for Synthesis of 1,2,4-Dithiazolidine-3,5-diones.
abstract: The Zumach-Weiss-Kühle (ZWK) reaction provides 1,2,4-dithiazolidine-3,5-diones [dithiasuccinoyl (Dts)-amines] by the rapid reaction of O-ethyl thiocarbamates plus (chlorocarbonyl)sulfenyl chloride, with ethyl chloride and hydrogen chloride being formed as coproducts, and carbamoyl chlorides or isocyanates generated as yield-diminishing byproducts. However, when the ZWK reaction is applied with (N-ethoxythiocarbonyl)urethane as the starting material, heterocyclization to the putative "Dts-urethane" does not occur. Instead, the reaction directly provides (chlorocarbonyl)(N-ethoxycarbonylcarbamoyl)disulfane, a reasonably stable crystalline compound; modified conditions stop at the (chlorocarbonyl)[1-ethoxy-(N-ethoxycarbonyl)formimidoyl]disulfane intermediate. The title (chlorocarbonyl)(carbamoyl)disulfane cannot be converted to the elusive Dts derivative, but rather gives (N-ethoxycarbonyl)carbamoyl chloride upon thermolysis, or (N-ethoxycarbonyl)isocyanate upon treatment with tertiary amines. Additional transformations of these compounds have been discovered, providing entries to both known and novel species. X-ray crystallographic structures are reported for the title (chlorocarbonyl)(carbamoyl)disulfane; for (methoxycarbonyl)(N-ethoxycarbonylcarbamoyl)disulfane, which is the corresponding adduct after quenching in methanol; for [1-ethoxy-(N-ethoxycarbonyl)formimidoyl](N'-methyl-N'-phenylcarbamoyl)disulfane, which is obtained by trapping the title intermediate with N-methylaniline; and for (N-ethoxycarbonylcarbamoyl)(N'-methyl-N'-phenylcarbamoyl)disulfane, which is a short-lived intermediate in the reaction of the title (chlorocarbonyl)(carbamoyl)disulfane with excess N-methylaniline. The new chemistry and structural information reported herein is expected to contribute to accurate modeling of the ZWK reaction trajectory.
authors.affiliation: Department of Chemistry, University of Minnesota , Minneapolis, Minnesota 55455, United States.
authors.forename: George
authors.initials: G
authors.lastname: Barany
authors.affiliation: Department of Chemistry, University of Minnesota , Minneapolis, Minnesota 55455, United States.
authors.forename: Doyle
authors.initials: D
authors.lastname: Britton
authors.affiliation: Department of Chemistry, University of Minnesota , Minneapolis, Minnesota 55455, United States.
authors.forename: Lin
authors.initials: L
authors.lastname: Chen
authors.affiliation: Department of Chemistry, University of Minnesota , Minneapolis, Minnesota 55455, United States.
authors.forename: Robert P
authors.initials: RP
authors.lastname: Hammer
authors.affiliation: Department of Chemistry, University of Minnesota , Minneapolis, Minnesota 55455, United States.
authors.forename: Madeleine J
authors.initials: MJ
authors.lastname: Henley
authors.affiliation: Department of Chemistry, University of Minnesota , Minneapolis, Minnesota 55455, United States.
authors.forename: Alex M
authors.initials: AM
authors.lastname: Schrader
authors.affiliation: Department of Chemistry, University of Minnesota , Minneapolis, Minnesota 55455, United States.
authors.forename: Victor G
authors.initials: VG
authors.lastname: Young
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry; D002219:Carbamates / Q000138:chemical synthesis* / Q000737:chemistry; D018360:Crystallography, X-Ray; D017953:Isocyanates / Q000737:chemistry; D015394:Molecular Structure; D013329:Structure-Activity Relationship; D013438:Sulfhydryl Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D045162:Thiazolidinediones / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: C000606077:(chlorocarbonyl)(N-ethoxycarbonylcarbamoyl)disulfane; C099736:1,2,4-dithiazolidine-3,5-dione; D000814:Aniline Compounds; D002219:Carbamates; D017953:Isocyanates; D013438:Sulfhydryl Compounds; D045162:Thiazolidinediones; C021313:methylaniline