The Quest for Carbenic Nitrile Imines: Experimental and Computational Characterization of C‐Amino Nitrile Imine

Abstract

C‐Amino nitrile imine has been generated as primary photoproduct (λ = 220 nm) of 5‐amino‐2H‐tetrazole isolated in an argon matrix at 15 K. Subsequent photochemical experiments (λ = 330 nm) demonstrated that C‐amino nitrile imine isomerizes to the corresponding three‐membered‐ring 1H‐diazirine and decomposes to methylenimine. The experimentally observed νas(CNN) absorption at 1998 cm–1 and a carbenic resonance structure contribution of around 20 %, predicted by natural resonance theory calculations, demonstrate that the protoproduced C‐amino nitrile imine has significant carbenic character. These results pave the way to the discovery of carbenic nitrile imines.

Surface reactions of aminosilane precursors during N2 plasma‐assisted atomic layer deposition of SiNx

“…Later, a similar observation was made by these authors for SiN x ALD with DSBAS and N 2 plasma . Based on an extensive survey of previous literature, especially on plasma‐deposited SiC x N y and CN x films, we have assigned the band at 2,080 cm −1 to the stretching vibration of C‐ and N‐containing cumulated double‐bonded species. In particular, the stretching vibrations for ketene imines (>C=C=N–) range from 2,000–2,060 cm −1 , and for diazo groups (>C=N + =N − ) from 2,000‐2,200 cm −1 .…”

“…Consistent with the deconvolution of the half‐cycle spectra, a clear contribution from cumulated double bonded –C x N y species can be observed at ~2,080 cm −1 in the SiN x films deposited from BDEAS (see inset for spectrum “b” in Figure ). The presence of cumulated double‐bonded –C x N y species is further confirmed by the weak broad feature at ~1,500 cm −1 in spectrum “b” in Figure , which was assigned to the C=N (imino) stretching mode in ketene imine and diazo species . Changes in this weak vibrational feature could not be observed in the infrared spectra for the individual BDEAS and N 2 plasma half‐cycles in spectra “c” and “d” in Figure .…”

“…Based on an extensive survey of previous literature, especially on plasma‐deposited SiC x N y and CN x films, we have assigned the band at 2,080 cm −1 to the stretching vibration of C‐ and N‐containing cumulated double‐bonded species. In particular, the stretching vibrations for ketene imines (>C=C=N–) range from 2,000–2,060 cm −1 , and for diazo groups (>C=N + =N − ) from 2,000‐2,200 cm −1 . Given that these vibrational frequencies can shift by tens of wavenumbers depending on their back bonding, it is very likely that the vibrational band at ~2,080 cm −1 is due to contributions from these two species .…”

On the Photochemistry of 1,2‐Benzisoxazole: Capture of Elusive Spiro‐2H‐azirine and Ketenimine Intermediates

“…[36] Irradiation Experiments: The matrices were irradiated through an external KBr window of the cryostat, using a tunable narrow-band beam provided by an optical parametric oscillator (pulse energy 1-3 mJ, fwhm ≈ 0.2 cm -1 ) pumped with a pulsed Nd:YAG laser (pulse duration 10 ns, repetition rate 10 Hz). The vapor of each sample was cocondensed with an excess of argon onto a CsI window cooled to 15 K. The cryostat system and FTIR spectrometer employed herein are described elsewhere.…”

Pyrolysis of hydrazine derivatives and related compounds with N N single bonds

“…370 M a n u s c r i p t [115,116,117]. This compound was identified in matrix photolyses of 651 aminotetrazoles [118,119]. Carbodiimides are known to be in thermal equilibrium with 652 cyanamides in the gas phase [12].…”