Lactamomethylsilanes – Synthesis, Structures, and Reactivity towards CO₂ and Phenylisocyanate

Abstract

Lactamomethylsilanes of γ-butyrolactam, δ-valerolactam, ε-caprolactam, and 1-isoindolinone (phthalimidine) with up to three methyl moieties were synthesized according to the chemical formula Me x SiLac (4-x) (x = 0, 1, 2, and 3). Using the lactams as starting materials four synthetic routes were tested: salt elimination, transsilylation, transamination, and metallation of the lactames followed by reaction 377 with methylchlorosilanes. All products were analyzed by NMR ( 1 H, 13 C and 29 Si) and RAMAN spectroscopy. Selected solid products were crystallized and the molecular structure was determined by single-crystal X-ray diffraction. The reactivity of the lactamomethylsilanes towards phenylisocyanate and CO 2 was studied.Si-O bond but less reactive than a Si-Cl bond. The Si-N bond is prone towards hydrolysis and alkoholysis. Additionally, some substances containing Si-N bonds react with heteroallenes like CO 2 and isocyanates via insertion reactions yielding useful products such as ureas, carbamates, and polysiloxanes, among others. [23][24][25][26] Therefore, in the presented study we have synthesized lactamomethylsilanes of the type Me x SiLac (4-x) (x = 0, 1, 2, and 3) [Lac = γ-butyrolactam, δ-valerolactam, εcaprolactam, and 1-isoindolinone (phthalimidine)] in order to investigate their structures and reactivities.

Two polymorphs of N,N′-diphenyl-2-[1-(propylamino)ethylidene]propanediamide

“…N,N 0 -Diphenyl-2-[1-(propylamino)ethylidene]propanediamide is an insertion product from an enamine and phenyl isocyanate. This was obtained in our work with different types of silicon-nitrogen compounds (Herbig et al, 2019a(Herbig et al, , 2021(Herbig et al, , 2022. The Si-N bonds can be subjected to insertion of different heteroallenes such as CO 2 and isocyanates (Kraushaar et al, 2012(Kraushaar et al, , 2014(Kraushaar et al, , 2017Herbig et al, 2018Herbig et al, , 2019b.…”

(E)-N-Phenyl-N-(phenylcarbamoyl)-3-[propyl(trimethylsilyl)amino]acrylamide chloroform hemisolvate

“…(E)-N-Phenyl-N-(phenylcarbamoyl)-3-[propyl(trimethylsilyl)amino]acrylamide is an insertion product from propyl(trimethylsilyl) [2-(trimethylsilyl)ethenyl]amine and phenyl isocyanate. It was obtained in the course of our work on different types of siliconnitrogen compounds (Herbig et al, 2019a(Herbig et al, , 2021(Herbig et al, , 2022. Si-N bonds can be subjected to the insertion of different heteroallenes such as CO 2 and isocyanates (Kraushaar et al, 2012(Kraushaar et al, , 2014(Kraushaar et al, , 2017Herbig et al, 2018Herbig et al, , 2019b.…”

Molecular Structures and Intermolecular Hydrogen Bonding of Silylated 2-Aminopyrimidines

“…The insertion of heteroallenes into Si-N bonds may also serve as an entry into silicon coordination chemistry (i.e., the syntheses of Si compounds with hexa-or pentacoordinate Si atom, VI [10] and VII [11], respectively). As part of those studies and of related investigations in our group, we synthesized a portfolio of aminosilanes and other compounds with Si-N bond(s), including silylated amines [6,9,12], imines [13], and cyclic aminosilanes [14], and explored their reactions with CO 2 or isocyanates. In addition, we have already investigated the reactivity of silyl morpholine towards a variety of heteroallenes [15].…”