New cyclic and spirocyclic aminosilanes

Abstract

New cyclic and spirocyclic aminosilanes were synthesised using ethylenediamine, 2-aminobenzylamine, 1,8-diaminonaphthalene, o-phenylenediamine, and trans-cyclohexane-1,2-diamine as starting material. These diamines were converted into aminosilanes using silicon tetrachloride and dimethyldichlorosilane directly and via the N,N’-bis(trimethylsilylated) amino derivatives. 15 new compounds of the type (diamino)(SiMe3)2, (diamino)2Si, (diamino)SiMe2, and (diamino)SiCl2 have been prepared. The formation of two cyclotrisilazane derivatives was observed starting from (N,N’-2-aminobenzylamino)dichlorosilane by trimerisation. All synthesised compounds have been characterised with NMR-, Raman-, or IR-spectroscopy, mass-spectrometry, and boiling or melting point. Single-crystal X-ray structure analyses of several derivatives have been performed. The degree of substitution with trimethylsilyl groups in the final compounds depends on the ring size of the spirocycles. It was shown with quantum chemical calculations on the M062X/6-31G(d) level that trimethylsilyl groups have a stabilising effect on 5-membered ring systems and a destabilising effect on 6-membered rings in these compounds.

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.…”