Infrared Spectroscopic Study of the Formamide-Na-Montmorillonite Complex. Conversion of s-Triazine to Formamide

Abstract

Abstract--The adsorption and degradation on montmorillonite of s-triazine, the parent compound of a major group of triazine-based herbicides, were studied by Fourier-transform infrared spectroscopy. The original s-triazine appeared to hydrolyze with residual bound water in montmorillonite at 20"C to produce formamide, which formed an intercalate with the clay. A mechanism for the conversion of s-triazine to formamide was proposed which does not support earlier reports that formic acid and ammonia are the reaction products. The infrared spectrum of the formamide-Na-montmorillonite intercalate suggests that formamide reacted with the exchangeable Na cation and that the NH2 group hydrogen bonded with the clay. Assuming the intercalated formamide molecule to be planar, the molecular plane was found to be inclined at ~33 ~ with respect to the plane of the silicate sheet. C-N and C-O bonds were also found to be tilted at the same angle with respect to the clay surface. The proposed orientation is in good agreement with the measured value of d (001) for the formamide-Na-montmorillonite complex. The proposed model of the formamide-montmorillonite complex serves as a basis for comparison of other clay-amide complexes that are important in protein-clay interactions.

Nature of organic fluid–montmorillonite interactions: An FTIR spectroscopic study

“…As seen in Fig. 1, the band at 1398 cm À1 is attributed to C-H in-plane bending vibration and the broad band around 1323 cm À1 is attributed to C-N stretching and N-H wagging vibrations [45]. The band at 1049 cm À1 is assigned to C-H out-of-plane bending vibrations [45].…”

“…C-O stretching vibration band is one of the most characteristic IR bands of methanol and lies in the 950 and 1100 cm À1 range [45][46][47][48] as shown in Fig. 5.…”

Genetics first or metabolism first? The formamide clue

“…Further concentration processes might have been favored by the presence of minerals, considering as an example the high efficiency of absorption of NH 2 CHO in clays of the montmorillonites family. 51,52 In the latter case, NH 2 CHO is included in the empty space between the layers of the mineral, mainly due to electrostatic interactions and hydrogen bonds with the oxygen or metal atoms present in the crystal. 53 These interactions may increase the reactivity of NH 2 CHO by increasing the electrophilic and nucleophilic properties of its functional groups (the amide and amino moieties).…”

Micro‐/Mesoporous conjugated polymer based on star‐shaped triazine‐functional triphenylamine framework as the performance‐improved cathode of Li‐organic battery

“…Also, the absorption peaks at 1276 and 820 cm −1 indicated the CN stretching from the tertiary amine and the CH out‐of‐plane vibration from 1,4‐disubstituted benzene rings. Besides, the formation of triazine ring inside PTDAPTz was manifested in the spectrum, in which the absorption peaks at 1364 and 1415 cm −1 represent both the CN “breathing” and the CN stretching in the triazine ring . Resonance Raman spectroscopy was further made to verify the structure of the polymer [shown in Fig.…”