Carbon Disulfide. III. Reaction with Active Methylene Compounds. The Infrared and Ultraviolet Spectra of the Desaurins

Abstract

The position of the carbonyl-stretching bands in the i.r. spectra of the desaurins, 2,4-bis(acy1methy-1ene)-and 2,4-bis(carboxymethy1ene)-l,3-dithetane derivatives, establishes that there is a strong interaction between the sulfur atoms and the carbonyl groups. This is considered to involve mainly conjugative interaction rather than interaction through space, although the latter may account for the abnormally weak intensity of the carbonyl-stretching bands. These bands are split in the case of several desaurins and related compounds, and evidence has been obtained in one case that the splitting is due to Fermi resonance. The U.V. spectra of the desaurins and related compounds also indicate a strong conjugative interaction between the sulfur atoms and the carbonyl groups.La position des bandes de vibration des carbonyles dans les spectres i.r. des disaurines, des derives des bi'sf~ylmethy1ene)-2,4 et bis(carboxymCthy1ene)-2,4 diethane-1,3, dtmontre qu'il existe une interaction forte entre les atomes de soufre et les groupes carbonyles. Ces rksultats proviendraient principalement d'une interaction conjugative plut6t que d'une interaction a travers I'espace, quoique cette derniere hypothese pourrait expliquer l'intensitk anormalement faible des bandes de vibration des carbonyles. Dans le cas de plusieurs dksaurines et composCs analogues, les bandes sont diviskes et des indications ont Cte obtenues dans un cas, que cette division est due a de la resonance de Fermi. Les spectres ultraviolets des dksaurines et des composes voisins indiquent aussi qu'une interaction conjugative forte existe entre les atomes de soufre et les groupes carbonyles. 's' these desaurins, it was considered to be of importance to compare them with the spectra of a desaurin derived from a dialkyl ketone. For personal use only.

Synthesis and Characterization of Novel Dinuclear Copper(I) Complexes. Dimerization of [CuL(PPh3)2] (L = methyl 3-hydroxy-3-(p-R-phenyl)-2-propenedithioate)

“…The IR spectra of copper complexes 6a − e show the ν(CC) vibration at 1520−1540 cm -1 , which is shifted to a wavenumber lower than that of free ligands 5 because of a major electron delocalization by complex formation. In the region of 1230−1320 cm -1 , the ν(CS) vibration splits in two signals, maybe because of Fermi resonance . The molecular ion [M + ] for complexes 5a − e is not observed on the MS−FAB+ analysis; however, the adduct [M + Cu] + was detected, similar to that in copper(I) complexes 4 …”

Novel dinuclear iron(0) complexes from α,β-unsaturated ketones β-positioned with sulfide and sulfoxide groups

“…From the mixture only 2d could be isolated and purified by chromatography on alumina, which was evidenced by 1 H and 13 C NMR spectra. This fact can be explained in terms of a strong electronic interaction between p and d orbital of oxygen and sulfur atoms through the conjugated system [12].…”

Synthesis and Reactions of 2-Alkylidene Thiiranes and Thietanes

“…57,[73][74][75][76][77] A relative lack of activity characterized this research area for some 50 years until the structure of the desaurins 170 ( Figure 8) was revisited by Yates and coworkers. In a series of papers concluding in 1971, a combination of chemical degradation, IR, NMR and UV spectroscopy and X-ray crystal structure analysis 58,78,79 was used to confirm the structure 170 originally proposed by Meyer 75,80 as the trans isomer.…”